13e519524SHoward Hinnant// -*- C++ -*-
23e519524SHoward Hinnant//===-------------------------- algorithm ---------------------------------===//
33e519524SHoward Hinnant//
45b08a8a4SHoward Hinnant//                     The LLVM Compiler Infrastructure
53e519524SHoward Hinnant//
6412dbebeSHoward Hinnant// This file is dual licensed under the MIT and the University of Illinois Open
7412dbebeSHoward Hinnant// Source Licenses. See LICENSE.TXT for details.
83e519524SHoward Hinnant//
93e519524SHoward Hinnant//===----------------------------------------------------------------------===//
103e519524SHoward Hinnant
113e519524SHoward Hinnant#ifndef _LIBCPP_ALGORITHM
123e519524SHoward Hinnant#define _LIBCPP_ALGORITHM
133e519524SHoward Hinnant
143e519524SHoward Hinnant/*
153e519524SHoward Hinnant    algorithm synopsis
163e519524SHoward Hinnant
173e519524SHoward Hinnant#include <initializer_list>
183e519524SHoward Hinnant
193e519524SHoward Hinnantnamespace std
203e519524SHoward Hinnant{
213e519524SHoward Hinnant
223e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
23706ffef7SMarshall Clow    constexpr bool     // constexpr in C++20
243e519524SHoward Hinnant    all_of(InputIterator first, InputIterator last, Predicate pred);
253e519524SHoward Hinnant
263e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
27706ffef7SMarshall Clow    constexpr bool     // constexpr in C++20
283e519524SHoward Hinnant    any_of(InputIterator first, InputIterator last, Predicate pred);
293e519524SHoward Hinnant
303e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
31706ffef7SMarshall Clow    constexpr bool     // constexpr in C++20
323e519524SHoward Hinnant    none_of(InputIterator first, InputIterator last, Predicate pred);
333e519524SHoward Hinnant
343e519524SHoward Hinnanttemplate <class InputIterator, class Function>
351b9a4ffdSMarshall Clow    constexpr Function          // constexpr in C++20
363e519524SHoward Hinnant    for_each(InputIterator first, InputIterator last, Function f);
373e519524SHoward Hinnant
38d5c65ffaSMarshall Clowtemplate<class InputIterator, class Size, class Function>
391b9a4ffdSMarshall Clow    constexpr InputIterator     // constexpr in C++20
401b9a4ffdSMarshall Clow    for_each_n(InputIterator first, Size n, Function f); // C++17
41d5c65ffaSMarshall Clow
423e519524SHoward Hinnanttemplate <class InputIterator, class T>
4349c7643cSMarshall Clow    constexpr InputIterator     // constexpr in C++20
443e519524SHoward Hinnant    find(InputIterator first, InputIterator last, const T& value);
453e519524SHoward Hinnant
463e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
4749c7643cSMarshall Clow    constexpr InputIterator     // constexpr in C++20
483e519524SHoward Hinnant    find_if(InputIterator first, InputIterator last, Predicate pred);
493e519524SHoward Hinnant
503e519524SHoward Hinnanttemplate<class InputIterator, class Predicate>
518694428eSMarshall Clow    InputIterator               // constexpr in C++20
523e519524SHoward Hinnant    find_if_not(InputIterator first, InputIterator last, Predicate pred);
533e519524SHoward Hinnant
543e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
558694428eSMarshall Clow    ForwardIterator1            // constexpr in C++20
563e519524SHoward Hinnant    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
573e519524SHoward Hinnant             ForwardIterator2 first2, ForwardIterator2 last2);
583e519524SHoward Hinnant
593e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
608694428eSMarshall Clow    ForwardIterator1            // constexpr in C++20
613e519524SHoward Hinnant    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
623e519524SHoward Hinnant             ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
633e519524SHoward Hinnant
643e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
658694428eSMarshall Clow    constexpr ForwardIterator1  // constexpr in C++20
663e519524SHoward Hinnant    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
673e519524SHoward Hinnant                  ForwardIterator2 first2, ForwardIterator2 last2);
683e519524SHoward Hinnant
693e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
708694428eSMarshall Clow    constexpr ForwardIterator1  // constexpr in C++20
713e519524SHoward Hinnant    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
723e519524SHoward Hinnant                  ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
733e519524SHoward Hinnant
743e519524SHoward Hinnanttemplate <class ForwardIterator>
758694428eSMarshall Clow    constexpr ForwardIterator   // constexpr in C++20
763e519524SHoward Hinnant    adjacent_find(ForwardIterator first, ForwardIterator last);
773e519524SHoward Hinnant
783e519524SHoward Hinnanttemplate <class ForwardIterator, class BinaryPredicate>
798694428eSMarshall Clow    constexpr ForwardIterator   // constexpr in C++20
803e519524SHoward Hinnant    adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
813e519524SHoward Hinnant
823e519524SHoward Hinnanttemplate <class InputIterator, class T>
83056f15e3SMarshall Clow    constexpr typename iterator_traits<InputIterator>::difference_type  // constexpr in C++20
843e519524SHoward Hinnant    count(InputIterator first, InputIterator last, const T& value);
853e519524SHoward Hinnant
863e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
87056f15e3SMarshall Clow    constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
883e519524SHoward Hinnant    count_if(InputIterator first, InputIterator last, Predicate pred);
893e519524SHoward Hinnant
903e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
916538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
923e519524SHoward Hinnant    mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
933e519524SHoward Hinnant
940b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2>
956538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
960b0bbd2fSMarshall Clow    mismatch(InputIterator1 first1, InputIterator1 last1,
970b0bbd2fSMarshall Clow             InputIterator2 first2, InputIterator2 last2); // **C++14**
980b0bbd2fSMarshall Clow
993e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1006538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
1013e519524SHoward Hinnant    mismatch(InputIterator1 first1, InputIterator1 last1,
1023e519524SHoward Hinnant             InputIterator2 first2, BinaryPredicate pred);
1033e519524SHoward Hinnant
1040b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1056538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
1060b0bbd2fSMarshall Clow    mismatch(InputIterator1 first1, InputIterator1 last1,
1070b0bbd2fSMarshall Clow             InputIterator2 first2, InputIterator2 last2,
1080b0bbd2fSMarshall Clow             BinaryPredicate pred); // **C++14**
1090b0bbd2fSMarshall Clow
1103e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
1116538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1123e519524SHoward Hinnant    equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
1133e519524SHoward Hinnant
1140b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2>
1156538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1160b0bbd2fSMarshall Clow    equal(InputIterator1 first1, InputIterator1 last1,
1170b0bbd2fSMarshall Clow          InputIterator2 first2, InputIterator2 last2); // **C++14**
1180b0bbd2fSMarshall Clow
1193e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1206538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1213e519524SHoward Hinnant    equal(InputIterator1 first1, InputIterator1 last1,
1223e519524SHoward Hinnant          InputIterator2 first2, BinaryPredicate pred);
1233e519524SHoward Hinnant
1240b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1256538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1260b0bbd2fSMarshall Clow    equal(InputIterator1 first1, InputIterator1 last1,
1270b0bbd2fSMarshall Clow          InputIterator2 first2, InputIterator2 last2,
1280b0bbd2fSMarshall Clow          BinaryPredicate pred); // **C++14**
1290b0bbd2fSMarshall Clow
1303e519524SHoward Hinnanttemplate<class ForwardIterator1, class ForwardIterator2>
13149c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1323e519524SHoward Hinnant    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1333e519524SHoward Hinnant                   ForwardIterator2 first2);
1343e519524SHoward Hinnant
1350b0bbd2fSMarshall Clowtemplate<class ForwardIterator1, class ForwardIterator2>
13649c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1370b0bbd2fSMarshall Clow    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1380b0bbd2fSMarshall Clow                   ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
1390b0bbd2fSMarshall Clow
1403e519524SHoward Hinnanttemplate<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
14149c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1423e519524SHoward Hinnant    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1433e519524SHoward Hinnant                   ForwardIterator2 first2, BinaryPredicate pred);
1443e519524SHoward Hinnant
1450b0bbd2fSMarshall Clowtemplate<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
14649c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1470b0bbd2fSMarshall Clow    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1480b0bbd2fSMarshall Clow                   ForwardIterator2 first2, ForwardIterator2 last2,
1490b0bbd2fSMarshall Clow                   BinaryPredicate pred);  // **C++14**
1500b0bbd2fSMarshall Clow
1513e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
15212f0a779SMarshall Clow    constexpr ForwardIterator1      // constexpr in C++20
1533e519524SHoward Hinnant    search(ForwardIterator1 first1, ForwardIterator1 last1,
1543e519524SHoward Hinnant           ForwardIterator2 first2, ForwardIterator2 last2);
1553e519524SHoward Hinnant
1563e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
15712f0a779SMarshall Clow    constexpr ForwardIterator1      // constexpr in C++20
1583e519524SHoward Hinnant    search(ForwardIterator1 first1, ForwardIterator1 last1,
1593e519524SHoward Hinnant           ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
1603e519524SHoward Hinnant
1613e519524SHoward Hinnanttemplate <class ForwardIterator, class Size, class T>
16212f0a779SMarshall Clow    constexpr ForwardIterator       // constexpr in C++20
1633e519524SHoward Hinnant    search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
1643e519524SHoward Hinnant
1653e519524SHoward Hinnanttemplate <class ForwardIterator, class Size, class T, class BinaryPredicate>
16612f0a779SMarshall Clow    constexpr ForwardIterator       // constexpr in C++20
1673e519524SHoward Hinnant    search_n(ForwardIterator first, ForwardIterator last,
1683e519524SHoward Hinnant             Size count, const T& value, BinaryPredicate pred);
1693e519524SHoward Hinnant
1703e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator>
1713e519524SHoward Hinnant    OutputIterator
1723e519524SHoward Hinnant    copy(InputIterator first, InputIterator last, OutputIterator result);
1733e519524SHoward Hinnant
1743e519524SHoward Hinnanttemplate<class InputIterator, class OutputIterator, class Predicate>
1753e519524SHoward Hinnant    OutputIterator
1763e519524SHoward Hinnant    copy_if(InputIterator first, InputIterator last,
1773e519524SHoward Hinnant            OutputIterator result, Predicate pred);
1783e519524SHoward Hinnant
1793e519524SHoward Hinnanttemplate<class InputIterator, class Size, class OutputIterator>
1803e519524SHoward Hinnant    OutputIterator
1813e519524SHoward Hinnant    copy_n(InputIterator first, Size n, OutputIterator result);
1823e519524SHoward Hinnant
1833e519524SHoward Hinnanttemplate <class BidirectionalIterator1, class BidirectionalIterator2>
1843e519524SHoward Hinnant    BidirectionalIterator2
1853e519524SHoward Hinnant    copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
1863e519524SHoward Hinnant                  BidirectionalIterator2 result);
1873e519524SHoward Hinnant
1883e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
1893e519524SHoward Hinnant    ForwardIterator2
1903e519524SHoward Hinnant    swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
1913e519524SHoward Hinnant
1923e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
1933e519524SHoward Hinnant    void
1943e519524SHoward Hinnant    iter_swap(ForwardIterator1 a, ForwardIterator2 b);
1953e519524SHoward Hinnant
1963e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class UnaryOperation>
19799894b61SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
1983e519524SHoward Hinnant    transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
1993e519524SHoward Hinnant
2003e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
20199894b61SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2023e519524SHoward Hinnant    transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
2033e519524SHoward Hinnant              OutputIterator result, BinaryOperation binary_op);
2043e519524SHoward Hinnant
2053e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
20612c7423fSMarshall Clow    constexpr void      // constexpr in C++20
2073e519524SHoward Hinnant    replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
2083e519524SHoward Hinnant
2093e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate, class T>
21012c7423fSMarshall Clow    constexpr void      // constexpr in C++20
2113e519524SHoward Hinnant    replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
2123e519524SHoward Hinnant
2133e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class T>
21412c7423fSMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2153e519524SHoward Hinnant    replace_copy(InputIterator first, InputIterator last, OutputIterator result,
2163e519524SHoward Hinnant                 const T& old_value, const T& new_value);
2173e519524SHoward Hinnant
2183e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class Predicate, class T>
21912c7423fSMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2203e519524SHoward Hinnant    replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
2213e519524SHoward Hinnant
2223e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
2234bfb9313SMarshall Clow    constexpr void      // constexpr in C++20
2243e519524SHoward Hinnant    fill(ForwardIterator first, ForwardIterator last, const T& value);
2253e519524SHoward Hinnant
2263e519524SHoward Hinnanttemplate <class OutputIterator, class Size, class T>
2274bfb9313SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2283e519524SHoward Hinnant    fill_n(OutputIterator first, Size n, const T& value);
2293e519524SHoward Hinnant
2303e519524SHoward Hinnanttemplate <class ForwardIterator, class Generator>
2314bfb9313SMarshall Clow    constexpr void      // constexpr in C++20
2323e519524SHoward Hinnant    generate(ForwardIterator first, ForwardIterator last, Generator gen);
2333e519524SHoward Hinnant
2343e519524SHoward Hinnanttemplate <class OutputIterator, class Size, class Generator>
2354bfb9313SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2363e519524SHoward Hinnant    generate_n(OutputIterator first, Size n, Generator gen);
2373e519524SHoward Hinnant
2383e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
239*e8ea8296SMarshall Clow    constexpr ForwardIterator     // constexpr in C++20
2403e519524SHoward Hinnant    remove(ForwardIterator first, ForwardIterator last, const T& value);
2413e519524SHoward Hinnant
2423e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate>
243*e8ea8296SMarshall Clow    constexpr ForwardIterator     // constexpr in C++20
2443e519524SHoward Hinnant    remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
2453e519524SHoward Hinnant
2463e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class T>
247*e8ea8296SMarshall Clow    constexpr OutputIterator     // constexpr in C++20
2483e519524SHoward Hinnant    remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
2493e519524SHoward Hinnant
2503e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class Predicate>
251*e8ea8296SMarshall Clow    constexpr OutputIterator     // constexpr in C++20
2523e519524SHoward Hinnant    remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
2533e519524SHoward Hinnant
2543e519524SHoward Hinnanttemplate <class ForwardIterator>
2553e519524SHoward Hinnant    ForwardIterator
2563e519524SHoward Hinnant    unique(ForwardIterator first, ForwardIterator last);
2573e519524SHoward Hinnant
2583e519524SHoward Hinnanttemplate <class ForwardIterator, class BinaryPredicate>
2593e519524SHoward Hinnant    ForwardIterator
2603e519524SHoward Hinnant    unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
2613e519524SHoward Hinnant
2623e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator>
2633e519524SHoward Hinnant    OutputIterator
2643e519524SHoward Hinnant    unique_copy(InputIterator first, InputIterator last, OutputIterator result);
2653e519524SHoward Hinnant
2663e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class BinaryPredicate>
2673e519524SHoward Hinnant    OutputIterator
2683e519524SHoward Hinnant    unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
2693e519524SHoward Hinnant
2703e519524SHoward Hinnanttemplate <class BidirectionalIterator>
2713e519524SHoward Hinnant    void
2723e519524SHoward Hinnant    reverse(BidirectionalIterator first, BidirectionalIterator last);
2733e519524SHoward Hinnant
2743e519524SHoward Hinnanttemplate <class BidirectionalIterator, class OutputIterator>
275*e8ea8296SMarshall Clow    constexpr OutputIterator       // constexpr in C++20
2763e519524SHoward Hinnant    reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
2773e519524SHoward Hinnant
2783e519524SHoward Hinnanttemplate <class ForwardIterator>
2793e519524SHoward Hinnant    ForwardIterator
2803e519524SHoward Hinnant    rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
2813e519524SHoward Hinnant
2823e519524SHoward Hinnanttemplate <class ForwardIterator, class OutputIterator>
2833e519524SHoward Hinnant    OutputIterator
2843e519524SHoward Hinnant    rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
2853e519524SHoward Hinnant
2863e519524SHoward Hinnanttemplate <class RandomAccessIterator>
2873e519524SHoward Hinnant    void
2880f37a410SMarshall Clow    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
2893e519524SHoward Hinnant
2903e519524SHoward Hinnanttemplate <class RandomAccessIterator, class RandomNumberGenerator>
2913e519524SHoward Hinnant    void
29206965c1fSMarshall Clow    random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
2930f37a410SMarshall Clow                   RandomNumberGenerator& rand);  // deprecated in C++14, removed in C++17
2943e519524SHoward Hinnant
295e7154709SEric Fiseliertemplate<class PopulationIterator, class SampleIterator,
296e7154709SEric Fiselier         class Distance, class UniformRandomBitGenerator>
297e7154709SEric Fiselier    SampleIterator sample(PopulationIterator first, PopulationIterator last,
298e7154709SEric Fiselier                          SampleIterator out, Distance n,
299e7154709SEric Fiselier                          UniformRandomBitGenerator&& g); // C++17
300e7154709SEric Fiselier
301f9d540b0SHoward Hinnanttemplate<class RandomAccessIterator, class UniformRandomNumberGenerator>
302f9d540b0SHoward Hinnant    void shuffle(RandomAccessIterator first, RandomAccessIterator last,
303fb340102SHoward Hinnant                 UniformRandomNumberGenerator&& g);
304f9d540b0SHoward Hinnant
3053e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
30649c7643cSMarshall Clow    constexpr bool  // constexpr in C++20
3073e519524SHoward Hinnant    is_partitioned(InputIterator first, InputIterator last, Predicate pred);
3083e519524SHoward Hinnant
3093e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate>
3103e519524SHoward Hinnant    ForwardIterator
3113e519524SHoward Hinnant    partition(ForwardIterator first, ForwardIterator last, Predicate pred);
3123e519524SHoward Hinnant
3133e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator1,
3143e519524SHoward Hinnant          class OutputIterator2, class Predicate>
3151b9a4ffdSMarshall Clow    constexpr pair<OutputIterator1, OutputIterator2>   // constexpr in C++20
3163e519524SHoward Hinnant    partition_copy(InputIterator first, InputIterator last,
3173e519524SHoward Hinnant                   OutputIterator1 out_true, OutputIterator2 out_false,
3183e519524SHoward Hinnant                   Predicate pred);
3193e519524SHoward Hinnant
3203e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate>
3213e519524SHoward Hinnant    ForwardIterator
3223e519524SHoward Hinnant    stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
3233e519524SHoward Hinnant
3243e519524SHoward Hinnanttemplate<class ForwardIterator, class Predicate>
325d57c03ddSMarshall Clow    constexpr ForwardIterator  // constexpr in C++20
3263e519524SHoward Hinnant    partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
3273e519524SHoward Hinnant
3283e519524SHoward Hinnanttemplate <class ForwardIterator>
32949c7643cSMarshall Clow    constexpr bool  // constexpr in C++20
3303e519524SHoward Hinnant    is_sorted(ForwardIterator first, ForwardIterator last);
3313e519524SHoward Hinnant
3323e519524SHoward Hinnanttemplate <class ForwardIterator, class Compare>
3333e519524SHoward Hinnant    bool
3343e519524SHoward Hinnant    is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
3353e519524SHoward Hinnant
3363e519524SHoward Hinnanttemplate<class ForwardIterator>
337056f15e3SMarshall Clow    constexpr ForwardIterator    // constexpr in C++20
3383e519524SHoward Hinnant    is_sorted_until(ForwardIterator first, ForwardIterator last);
3393e519524SHoward Hinnant
3403e519524SHoward Hinnanttemplate <class ForwardIterator, class Compare>
341056f15e3SMarshall Clow    constexpr ForwardIterator    // constexpr in C++20
3423e519524SHoward Hinnant    is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
3433e519524SHoward Hinnant
3443e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3453e519524SHoward Hinnant    void
3463e519524SHoward Hinnant    sort(RandomAccessIterator first, RandomAccessIterator last);
3473e519524SHoward Hinnant
3483e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3493e519524SHoward Hinnant    void
3503e519524SHoward Hinnant    sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
3513e519524SHoward Hinnant
3523e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3533e519524SHoward Hinnant    void
3543e519524SHoward Hinnant    stable_sort(RandomAccessIterator first, RandomAccessIterator last);
3553e519524SHoward Hinnant
3563e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3573e519524SHoward Hinnant    void
3583e519524SHoward Hinnant    stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
3593e519524SHoward Hinnant
3603e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3613e519524SHoward Hinnant    void
3623e519524SHoward Hinnant    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
3633e519524SHoward Hinnant
3643e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3653e519524SHoward Hinnant    void
3663e519524SHoward Hinnant    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
3673e519524SHoward Hinnant
3683e519524SHoward Hinnanttemplate <class InputIterator, class RandomAccessIterator>
3693e519524SHoward Hinnant    RandomAccessIterator
3703e519524SHoward Hinnant    partial_sort_copy(InputIterator first, InputIterator last,
3713e519524SHoward Hinnant                      RandomAccessIterator result_first, RandomAccessIterator result_last);
3723e519524SHoward Hinnant
3733e519524SHoward Hinnanttemplate <class InputIterator, class RandomAccessIterator, class Compare>
3743e519524SHoward Hinnant    RandomAccessIterator
3753e519524SHoward Hinnant    partial_sort_copy(InputIterator first, InputIterator last,
3763e519524SHoward Hinnant                      RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
3773e519524SHoward Hinnant
3783e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3793e519524SHoward Hinnant    void
3803e519524SHoward Hinnant    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
3813e519524SHoward Hinnant
3823e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3833e519524SHoward Hinnant    void
3843e519524SHoward Hinnant    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
3853e519524SHoward Hinnant
3863e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
387d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3883e519524SHoward Hinnant    lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
3893e519524SHoward Hinnant
3903e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
391d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3923e519524SHoward Hinnant    lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
3933e519524SHoward Hinnant
3943e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
395d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3963e519524SHoward Hinnant    upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
3973e519524SHoward Hinnant
3983e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
399d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
4003e519524SHoward Hinnant    upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4013e519524SHoward Hinnant
4023e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
403d57c03ddSMarshall Clow    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
4043e519524SHoward Hinnant    equal_range(ForwardIterator first, ForwardIterator last, const T& value);
4053e519524SHoward Hinnant
4063e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
407d57c03ddSMarshall Clow    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
4083e519524SHoward Hinnant    equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4093e519524SHoward Hinnant
4103e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
411d57c03ddSMarshall Clow    constexpr bool                                    // constexpr in C++20
4123e519524SHoward Hinnant    binary_search(ForwardIterator first, ForwardIterator last, const T& value);
4133e519524SHoward Hinnant
4143e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
415d57c03ddSMarshall Clow    bool  // constexpr in C++20
4163e519524SHoward Hinnant    binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4173e519524SHoward Hinnant
4183e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4193e519524SHoward Hinnant    OutputIterator
4203e519524SHoward Hinnant    merge(InputIterator1 first1, InputIterator1 last1,
4213e519524SHoward Hinnant          InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4223e519524SHoward Hinnant
4233e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4243e519524SHoward Hinnant    OutputIterator
4253e519524SHoward Hinnant    merge(InputIterator1 first1, InputIterator1 last1,
4263e519524SHoward Hinnant          InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4273e519524SHoward Hinnant
4283e519524SHoward Hinnanttemplate <class BidirectionalIterator>
4293e519524SHoward Hinnant    void
4303e519524SHoward Hinnant    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
4313e519524SHoward Hinnant
4323e519524SHoward Hinnanttemplate <class BidirectionalIterator, class Compare>
4333e519524SHoward Hinnant    void
4343e519524SHoward Hinnant    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
4353e519524SHoward Hinnant
4363e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
4373e519524SHoward Hinnant    bool
4383e519524SHoward Hinnant    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
4393e519524SHoward Hinnant
4403e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class Compare>
4413e519524SHoward Hinnant    bool
4423e519524SHoward Hinnant    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
4433e519524SHoward Hinnant
4443e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4453e519524SHoward Hinnant    OutputIterator
4463e519524SHoward Hinnant    set_union(InputIterator1 first1, InputIterator1 last1,
4473e519524SHoward Hinnant              InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4483e519524SHoward Hinnant
4493e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4503e519524SHoward Hinnant    OutputIterator
4513e519524SHoward Hinnant    set_union(InputIterator1 first1, InputIterator1 last1,
4523e519524SHoward Hinnant              InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4533e519524SHoward Hinnant
4543e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4553e519524SHoward Hinnant    OutputIterator
4563e519524SHoward Hinnant    set_intersection(InputIterator1 first1, InputIterator1 last1,
4573e519524SHoward Hinnant                     InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4583e519524SHoward Hinnant
4593e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4603e519524SHoward Hinnant    OutputIterator
4613e519524SHoward Hinnant    set_intersection(InputIterator1 first1, InputIterator1 last1,
4623e519524SHoward Hinnant                     InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4633e519524SHoward Hinnant
4643e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4653e519524SHoward Hinnant    OutputIterator
4663e519524SHoward Hinnant    set_difference(InputIterator1 first1, InputIterator1 last1,
4673e519524SHoward Hinnant                   InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4683e519524SHoward Hinnant
4693e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4703e519524SHoward Hinnant    OutputIterator
4713e519524SHoward Hinnant    set_difference(InputIterator1 first1, InputIterator1 last1,
4723e519524SHoward Hinnant                   InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4733e519524SHoward Hinnant
4743e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4753e519524SHoward Hinnant    OutputIterator
4763e519524SHoward Hinnant    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
4773e519524SHoward Hinnant                             InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4783e519524SHoward Hinnant
4793e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4803e519524SHoward Hinnant    OutputIterator
4813e519524SHoward Hinnant    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
4823e519524SHoward Hinnant                             InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4833e519524SHoward Hinnant
4843e519524SHoward Hinnanttemplate <class RandomAccessIterator>
4853e519524SHoward Hinnant    void
4863e519524SHoward Hinnant    push_heap(RandomAccessIterator first, RandomAccessIterator last);
4873e519524SHoward Hinnant
4883e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
4893e519524SHoward Hinnant    void
4903e519524SHoward Hinnant    push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
4913e519524SHoward Hinnant
4923e519524SHoward Hinnanttemplate <class RandomAccessIterator>
4933e519524SHoward Hinnant    void
4943e519524SHoward Hinnant    pop_heap(RandomAccessIterator first, RandomAccessIterator last);
4953e519524SHoward Hinnant
4963e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
4973e519524SHoward Hinnant    void
4983e519524SHoward Hinnant    pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
4993e519524SHoward Hinnant
5003e519524SHoward Hinnanttemplate <class RandomAccessIterator>
5013e519524SHoward Hinnant    void
5023e519524SHoward Hinnant    make_heap(RandomAccessIterator first, RandomAccessIterator last);
5033e519524SHoward Hinnant
5043e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
5053e519524SHoward Hinnant    void
5063e519524SHoward Hinnant    make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
5073e519524SHoward Hinnant
5083e519524SHoward Hinnanttemplate <class RandomAccessIterator>
5093e519524SHoward Hinnant    void
5103e519524SHoward Hinnant    sort_heap(RandomAccessIterator first, RandomAccessIterator last);
5113e519524SHoward Hinnant
5123e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
5133e519524SHoward Hinnant    void
5143e519524SHoward Hinnant    sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
5153e519524SHoward Hinnant
5163e519524SHoward Hinnanttemplate <class RandomAccessIterator>
51749c7643cSMarshall Clow    constexpr bool   // constexpr in C++20
5183e519524SHoward Hinnant    is_heap(RandomAccessIterator first, RandomAccessiterator last);
5193e519524SHoward Hinnant
5203e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
52149c7643cSMarshall Clow    constexpr bool   // constexpr in C++20
5223e519524SHoward Hinnant    is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
5233e519524SHoward Hinnant
5243e519524SHoward Hinnanttemplate <class RandomAccessIterator>
52549c7643cSMarshall Clow    constexpr RandomAccessIterator   // constexpr in C++20
5263e519524SHoward Hinnant    is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
5273e519524SHoward Hinnant
5283e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
52949c7643cSMarshall Clow    constexpr RandomAccessIterator   // constexpr in C++20
5303e519524SHoward Hinnant    is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
5313e519524SHoward Hinnant
5324eb27b79SHoward Hinnanttemplate <class ForwardIterator>
5334eb27b79SHoward Hinnant    ForwardIterator
5340b0671aeSMarshall Clow    min_element(ForwardIterator first, ForwardIterator last);  // constexpr in C++14
5354eb27b79SHoward Hinnant
5364eb27b79SHoward Hinnanttemplate <class ForwardIterator, class Compare>
5374eb27b79SHoward Hinnant    ForwardIterator
5380b0671aeSMarshall Clow    min_element(ForwardIterator first, ForwardIterator last, Compare comp);  // constexpr in C++14
5394eb27b79SHoward Hinnant
5403e519524SHoward Hinnanttemplate <class T>
5413e519524SHoward Hinnant    const T&
5429d67c6d5SMarshall Clow    min(const T& a, const T& b);  // constexpr in C++14
5433e519524SHoward Hinnant
5443e519524SHoward Hinnanttemplate <class T, class Compare>
5453e519524SHoward Hinnant    const T&
5469d67c6d5SMarshall Clow    min(const T& a, const T& b, Compare comp);  // constexpr in C++14
5473e519524SHoward Hinnant
5483e519524SHoward Hinnanttemplate<class T>
5494eb27b79SHoward Hinnant    T
5509d67c6d5SMarshall Clow    min(initializer_list<T> t);  // constexpr in C++14
5513e519524SHoward Hinnant
5523e519524SHoward Hinnanttemplate<class T, class Compare>
5534eb27b79SHoward Hinnant    T
5549d67c6d5SMarshall Clow    min(initializer_list<T> t, Compare comp);  // constexpr in C++14
5553e519524SHoward Hinnant
556146c14acSMarshall Clowtemplate<class T>
557146c14acSMarshall Clow    constexpr const T& clamp( const T& v, const T& lo, const T& hi );               // C++17
558146c14acSMarshall Clow
559146c14acSMarshall Clowtemplate<class T, class Compare>
560146c14acSMarshall Clow    constexpr const T& clamp( const T& v, const T& lo, const T& hi, Compare comp ); // C++17
561146c14acSMarshall Clow
5623e519524SHoward Hinnanttemplate <class ForwardIterator>
5633e519524SHoward Hinnant    ForwardIterator
5640b0671aeSMarshall Clow    max_element(ForwardIterator first, ForwardIterator last);  // constexpr in C++14
5653e519524SHoward Hinnant
5663e519524SHoward Hinnanttemplate <class ForwardIterator, class Compare>
5673e519524SHoward Hinnant    ForwardIterator
5680b0671aeSMarshall Clow    max_element(ForwardIterator first, ForwardIterator last, Compare comp);  // constexpr in C++14
5693e519524SHoward Hinnant
5704eb27b79SHoward Hinnanttemplate <class T>
5714eb27b79SHoward Hinnant    const T&
5729d67c6d5SMarshall Clow    max(const T& a, const T& b); // constexpr in C++14
5734eb27b79SHoward Hinnant
5744eb27b79SHoward Hinnanttemplate <class T, class Compare>
5754eb27b79SHoward Hinnant    const T&
5769d67c6d5SMarshall Clow    max(const T& a, const T& b, Compare comp);  // constexpr in C++14
5774eb27b79SHoward Hinnant
5784eb27b79SHoward Hinnanttemplate<class T>
5794eb27b79SHoward Hinnant    T
5809d67c6d5SMarshall Clow    max(initializer_list<T> t);  // constexpr in C++14
5814eb27b79SHoward Hinnant
5824eb27b79SHoward Hinnanttemplate<class T, class Compare>
5834eb27b79SHoward Hinnant    T
5849d67c6d5SMarshall Clow    max(initializer_list<T> t, Compare comp);  // constexpr in C++14
5854eb27b79SHoward Hinnant
5864eb27b79SHoward Hinnanttemplate<class ForwardIterator>
5874eb27b79SHoward Hinnant    pair<ForwardIterator, ForwardIterator>
5880b0671aeSMarshall Clow    minmax_element(ForwardIterator first, ForwardIterator last);   // constexpr in C++14
5894eb27b79SHoward Hinnant
5904eb27b79SHoward Hinnanttemplate<class ForwardIterator, class Compare>
5914eb27b79SHoward Hinnant    pair<ForwardIterator, ForwardIterator>
5920b0671aeSMarshall Clow    minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);   // constexpr in C++14
5934eb27b79SHoward Hinnant
5944eb27b79SHoward Hinnanttemplate<class T>
5954eb27b79SHoward Hinnant    pair<const T&, const T&>
5969d67c6d5SMarshall Clow    minmax(const T& a, const T& b);  // constexpr in C++14
5974eb27b79SHoward Hinnant
5984eb27b79SHoward Hinnanttemplate<class T, class Compare>
5994eb27b79SHoward Hinnant    pair<const T&, const T&>
6009d67c6d5SMarshall Clow    minmax(const T& a, const T& b, Compare comp);  // constexpr in C++14
6014eb27b79SHoward Hinnant
6024eb27b79SHoward Hinnanttemplate<class T>
6034eb27b79SHoward Hinnant    pair<T, T>
6049d67c6d5SMarshall Clow    minmax(initializer_list<T> t);  // constexpr in C++14
6054eb27b79SHoward Hinnant
6064eb27b79SHoward Hinnanttemplate<class T, class Compare>
6074eb27b79SHoward Hinnant    pair<T, T>
6089d67c6d5SMarshall Clow    minmax(initializer_list<T> t, Compare comp);  // constexpr in C++14
6094eb27b79SHoward Hinnant
6103e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
6111b9a4ffdSMarshall Clow    constexpr bool     // constexpr in C++20
6123e519524SHoward Hinnant    lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
6133e519524SHoward Hinnant
6143e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class Compare>
6151b9a4ffdSMarshall Clow    constexpr bool     // constexpr in C++20
6163e519524SHoward Hinnant    lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
6173e519524SHoward Hinnant                            InputIterator2 first2, InputIterator2 last2, Compare comp);
6183e519524SHoward Hinnant
6193e519524SHoward Hinnanttemplate <class BidirectionalIterator>
6203e519524SHoward Hinnant    bool
6213e519524SHoward Hinnant    next_permutation(BidirectionalIterator first, BidirectionalIterator last);
6223e519524SHoward Hinnant
6233e519524SHoward Hinnanttemplate <class BidirectionalIterator, class Compare>
6243e519524SHoward Hinnant    bool
6253e519524SHoward Hinnant    next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
6263e519524SHoward Hinnant
6273e519524SHoward Hinnanttemplate <class BidirectionalIterator>
6283e519524SHoward Hinnant    bool
6293e519524SHoward Hinnant    prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
6303e519524SHoward Hinnant
6313e519524SHoward Hinnanttemplate <class BidirectionalIterator, class Compare>
6323e519524SHoward Hinnant    bool
6333e519524SHoward Hinnant    prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
6343e519524SHoward Hinnant
6353e519524SHoward Hinnant}  // std
6363e519524SHoward Hinnant
6373e519524SHoward Hinnant*/
6383e519524SHoward Hinnant
6393e519524SHoward Hinnant#include <__config>
6403e519524SHoward Hinnant#include <initializer_list>
6413e519524SHoward Hinnant#include <type_traits>
6423e519524SHoward Hinnant#include <cstring>
643f07dd8d0SEric Fiselier#include <utility> // needed to provide swap_ranges.
6443e519524SHoward Hinnant#include <memory>
645d835e592SMarshall Clow#include <functional>
6463e519524SHoward Hinnant#include <iterator>
647a1d07d57SHoward Hinnant#include <cstddef>
6483e519524SHoward Hinnant
6495d1a701dSHoward Hinnant#if defined(__IBMCPP__)
6505d1a701dSHoward Hinnant#include "support/ibm/support.h"
6515d1a701dSHoward Hinnant#endif
6525d50aa32SEric Fiselier#if defined(_LIBCPP_COMPILER_MSVC)
65380f8cfb3SEric Fiselier#include <intrin.h>
6545f878d4bSHoward Hinnant#endif
6555d1a701dSHoward Hinnant
656c1bd9197SEric Fiselier#include <__debug>
657c1bd9197SEric Fiselier
658073458b1SHoward Hinnant#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
6593e519524SHoward Hinnant#pragma GCC system_header
660073458b1SHoward Hinnant#endif
6613e519524SHoward Hinnant
662a016efb1SEric Fiselier_LIBCPP_PUSH_MACROS
663a016efb1SEric Fiselier#include <__undef_macros>
664a016efb1SEric Fiselier
665a016efb1SEric Fiselier
6663e519524SHoward Hinnant_LIBCPP_BEGIN_NAMESPACE_STD
6673e519524SHoward Hinnant
6689d67c6d5SMarshall Clow// I'd like to replace these with _VSTD::equal_to<void>, but can't because:
6699d67c6d5SMarshall Clow//   * That only works with C++14 and later, and
6709d67c6d5SMarshall Clow//   * We haven't included <functional> here.
6713e519524SHoward Hinnanttemplate <class _T1, class _T2 = _T1>
6723e519524SHoward Hinnantstruct __equal_to
6733e519524SHoward Hinnant{
6743e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6753e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY bool operator()(const _T1& __x, const _T2& __y) const {return __x == __y;}
6763e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY bool operator()(const _T2& __x, const _T1& __y) const {return __x == __y;}
6773e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY bool operator()(const _T2& __x, const _T2& __y) const {return __x == __y;}
6783e519524SHoward Hinnant};
6793e519524SHoward Hinnant
6803e519524SHoward Hinnanttemplate <class _T1>
6813e519524SHoward Hinnantstruct __equal_to<_T1, _T1>
6823e519524SHoward Hinnant{
6839d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6849d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6853e519524SHoward Hinnant};
6863e519524SHoward Hinnant
6873e519524SHoward Hinnanttemplate <class _T1>
6883e519524SHoward Hinnantstruct __equal_to<const _T1, _T1>
6893e519524SHoward Hinnant{
6909d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6919d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6923e519524SHoward Hinnant};
6933e519524SHoward Hinnant
6943e519524SHoward Hinnanttemplate <class _T1>
6953e519524SHoward Hinnantstruct __equal_to<_T1, const _T1>
6963e519524SHoward Hinnant{
6979d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6989d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6993e519524SHoward Hinnant};
7003e519524SHoward Hinnant
7013e519524SHoward Hinnanttemplate <class _T1, class _T2 = _T1>
7023e519524SHoward Hinnantstruct __less
7033e519524SHoward Hinnant{
7049d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7059d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7069d67c6d5SMarshall Clow
7079d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7089d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T2& __y) const {return __x < __y;}
7099d67c6d5SMarshall Clow
7109d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7119d67c6d5SMarshall Clow    bool operator()(const _T2& __x, const _T1& __y) const {return __x < __y;}
7129d67c6d5SMarshall Clow
7139d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7149d67c6d5SMarshall Clow    bool operator()(const _T2& __x, const _T2& __y) const {return __x < __y;}
7153e519524SHoward Hinnant};
7163e519524SHoward Hinnant
7173e519524SHoward Hinnanttemplate <class _T1>
7183e519524SHoward Hinnantstruct __less<_T1, _T1>
7193e519524SHoward Hinnant{
7209d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7219d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7223e519524SHoward Hinnant};
7233e519524SHoward Hinnant
7243e519524SHoward Hinnanttemplate <class _T1>
7253e519524SHoward Hinnantstruct __less<const _T1, _T1>
7263e519524SHoward Hinnant{
7279d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7289d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7293e519524SHoward Hinnant};
7303e519524SHoward Hinnant
7313e519524SHoward Hinnanttemplate <class _T1>
7323e519524SHoward Hinnantstruct __less<_T1, const _T1>
7333e519524SHoward Hinnant{
7349d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7359d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7363e519524SHoward Hinnant};
7373e519524SHoward Hinnant
7383e519524SHoward Hinnanttemplate <class _Predicate>
739a763b36fSMarshall Clowclass __invert // invert the sense of a comparison
7403e519524SHoward Hinnant{
7413e519524SHoward Hinnantprivate:
7423e519524SHoward Hinnant    _Predicate __p_;
7433e519524SHoward Hinnantpublic:
744a763b36fSMarshall Clow    _LIBCPP_INLINE_VISIBILITY __invert() {}
7453e519524SHoward Hinnant
7463e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
747a763b36fSMarshall Clow    explicit __invert(_Predicate __p) : __p_(__p) {}
7483e519524SHoward Hinnant
7493e519524SHoward Hinnant    template <class _T1>
7503e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
7513e519524SHoward Hinnant    bool operator()(const _T1& __x) {return !__p_(__x);}
7523e519524SHoward Hinnant
7533e519524SHoward Hinnant    template <class _T1, class _T2>
7543e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
755a763b36fSMarshall Clow    bool operator()(const _T1& __x, const _T2& __y) {return __p_(__y, __x);}
7563e519524SHoward Hinnant};
7573e519524SHoward Hinnant
758145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
7593e519524SHoward Hinnant
7603e519524SHoward Hinnanttemplate <class _Compare>
7613e519524SHoward Hinnantstruct __debug_less
7623e519524SHoward Hinnant{
7633e519524SHoward Hinnant    _Compare __comp_;
7643e519524SHoward Hinnant    __debug_less(_Compare& __c) : __comp_(__c) {}
765331d2159SEric Fiselier
7663e519524SHoward Hinnant    template <class _Tp, class _Up>
7673e519524SHoward Hinnant    bool operator()(const _Tp& __x, const _Up& __y)
7683e519524SHoward Hinnant    {
7693e519524SHoward Hinnant        bool __r = __comp_(__x, __y);
7703e519524SHoward Hinnant        if (__r)
771331d2159SEric Fiselier            __do_compare_assert(0, __y, __x);
7723e519524SHoward Hinnant        return __r;
7733e519524SHoward Hinnant    }
774331d2159SEric Fiselier
775331d2159SEric Fiselier    template <class _LHS, class _RHS>
776331d2159SEric Fiselier    inline _LIBCPP_INLINE_VISIBILITY
777331d2159SEric Fiselier    decltype((void)_VSTD::declval<_Compare&>()(
778331d2159SEric Fiselier        _VSTD::declval<_LHS const&>(), _VSTD::declval<_RHS const&>()))
779331d2159SEric Fiselier    __do_compare_assert(int, _LHS const& __l, _RHS const& __r) {
780331d2159SEric Fiselier        _LIBCPP_ASSERT(!__comp_(__l, __r),
781331d2159SEric Fiselier            "Comparator does not induce a strict weak ordering");
782331d2159SEric Fiselier    }
783331d2159SEric Fiselier
784331d2159SEric Fiselier    template <class _LHS, class _RHS>
785331d2159SEric Fiselier    inline _LIBCPP_INLINE_VISIBILITY
786331d2159SEric Fiselier    void __do_compare_assert(long, _LHS const&, _RHS const&) {}
7873e519524SHoward Hinnant};
7883e519524SHoward Hinnant
789145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
7903e519524SHoward Hinnant
791c8edcb36SHoward Hinnant// Precondition:  __x != 0
792c206366fSHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
79380f8cfb3SEric Fiselierunsigned __ctz(unsigned __x) {
79480f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
795c206366fSHoward Hinnant    return static_cast<unsigned>(__builtin_ctz(__x));
79680f8cfb3SEric Fiselier#else
79780f8cfb3SEric Fiselier  static_assert(sizeof(unsigned) == sizeof(unsigned long), "");
79880f8cfb3SEric Fiselier  static_assert(sizeof(unsigned long) == 4, "");
79980f8cfb3SEric Fiselier  unsigned long where;
80080f8cfb3SEric Fiselier  // Search from LSB to MSB for first set bit.
80180f8cfb3SEric Fiselier  // Returns zero if no set bit is found.
8029a0a0045SShoaib Meenai  if (_BitScanForward(&where, __x))
80380f8cfb3SEric Fiselier    return where;
80480f8cfb3SEric Fiselier  return 32;
80580f8cfb3SEric Fiselier#endif
806c206366fSHoward Hinnant}
807c206366fSHoward Hinnant
808c206366fSHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
80980f8cfb3SEric Fiselierunsigned long __ctz(unsigned long __x) {
81080f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
811c206366fSHoward Hinnant    return static_cast<unsigned long>(__builtin_ctzl(__x));
81280f8cfb3SEric Fiselier#else
81380f8cfb3SEric Fiselier    static_assert(sizeof(unsigned long) == sizeof(unsigned), "");
81480f8cfb3SEric Fiselier    return __ctz(static_cast<unsigned>(__x));
81580f8cfb3SEric Fiselier#endif
816c206366fSHoward Hinnant}
817c206366fSHoward Hinnant
818c206366fSHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
81980f8cfb3SEric Fiselierunsigned long long __ctz(unsigned long long __x) {
82080f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
821c206366fSHoward Hinnant    return static_cast<unsigned long long>(__builtin_ctzll(__x));
82280f8cfb3SEric Fiselier#else
82380f8cfb3SEric Fiselier    unsigned long where;
82480f8cfb3SEric Fiselier// Search from LSB to MSB for first set bit.
82580f8cfb3SEric Fiselier// Returns zero if no set bit is found.
82680f8cfb3SEric Fiselier#if defined(_LIBCPP_HAS_BITSCAN64)
82780f8cfb3SEric Fiselier    (defined(_M_AMD64) || defined(__x86_64__))
8289a0a0045SShoaib Meenai  if (_BitScanForward64(&where, __x))
82980f8cfb3SEric Fiselier    return static_cast<int>(where);
83080f8cfb3SEric Fiselier#else
83180f8cfb3SEric Fiselier  // Win32 doesn't have _BitScanForward64 so emulate it with two 32 bit calls.
83280f8cfb3SEric Fiselier  // Scan the Low Word.
8339a0a0045SShoaib Meenai  if (_BitScanForward(&where, static_cast<unsigned long>(__x)))
83480f8cfb3SEric Fiselier    return where;
83580f8cfb3SEric Fiselier  // Scan the High Word.
8369a0a0045SShoaib Meenai  if (_BitScanForward(&where, static_cast<unsigned long>(__x >> 32)))
83780f8cfb3SEric Fiselier    return where + 32; // Create a bit offset from the LSB.
83880f8cfb3SEric Fiselier#endif
83980f8cfb3SEric Fiselier  return 64;
84080f8cfb3SEric Fiselier#endif // _LIBCPP_COMPILER_MSVC
841c206366fSHoward Hinnant}
842c8edcb36SHoward Hinnant
843c8edcb36SHoward Hinnant// Precondition:  __x != 0
844c206366fSHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
84580f8cfb3SEric Fiselierunsigned __clz(unsigned __x) {
84680f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
847c206366fSHoward Hinnant    return static_cast<unsigned>(__builtin_clz(__x));
84880f8cfb3SEric Fiselier#else
84980f8cfb3SEric Fiselier  static_assert(sizeof(unsigned) == sizeof(unsigned long), "");
85080f8cfb3SEric Fiselier  static_assert(sizeof(unsigned long) == 4, "");
85180f8cfb3SEric Fiselier  unsigned long where;
85280f8cfb3SEric Fiselier  // Search from LSB to MSB for first set bit.
85380f8cfb3SEric Fiselier  // Returns zero if no set bit is found.
8549a0a0045SShoaib Meenai  if (_BitScanReverse(&where, __x))
85580f8cfb3SEric Fiselier    return 31 - where;
85680f8cfb3SEric Fiselier  return 32; // Undefined Behavior.
85780f8cfb3SEric Fiselier#endif
858c206366fSHoward Hinnant}
859c206366fSHoward Hinnant
860c206366fSHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
86180f8cfb3SEric Fiselierunsigned long __clz(unsigned long __x) {
86280f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
863c206366fSHoward Hinnant    return static_cast<unsigned long>(__builtin_clzl (__x));
86480f8cfb3SEric Fiselier#else
86580f8cfb3SEric Fiselier    static_assert(sizeof(unsigned) == sizeof(unsigned long), "");
86680f8cfb3SEric Fiselier    return __clz(static_cast<unsigned>(__x));
86780f8cfb3SEric Fiselier#endif
868c206366fSHoward Hinnant}
869c206366fSHoward Hinnant
870c206366fSHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
87180f8cfb3SEric Fiselierunsigned long long __clz(unsigned long long __x) {
87280f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
873c206366fSHoward Hinnant    return static_cast<unsigned long long>(__builtin_clzll(__x));
87480f8cfb3SEric Fiselier#else
87580f8cfb3SEric Fiselier  unsigned long where;
87680f8cfb3SEric Fiselier// BitScanReverse scans from MSB to LSB for first set bit.
87780f8cfb3SEric Fiselier// Returns 0 if no set bit is found.
87880f8cfb3SEric Fiselier#if defined(_LIBCPP_HAS_BITSCAN64)
8799a0a0045SShoaib Meenai  if (_BitScanReverse64(&where, __x))
88080f8cfb3SEric Fiselier    return static_cast<int>(63 - where);
88180f8cfb3SEric Fiselier#else
88280f8cfb3SEric Fiselier  // Scan the high 32 bits.
8839a0a0045SShoaib Meenai  if (_BitScanReverse(&where, static_cast<unsigned long>(__x >> 32)))
88480f8cfb3SEric Fiselier    return 63 - (where + 32); // Create a bit offset from the MSB.
88580f8cfb3SEric Fiselier  // Scan the low 32 bits.
8869a0a0045SShoaib Meenai  if (_BitScanReverse(&where, static_cast<unsigned long>(__x)))
88780f8cfb3SEric Fiselier    return 63 - where;
88880f8cfb3SEric Fiselier#endif
88980f8cfb3SEric Fiselier  return 64; // Undefined Behavior.
89080f8cfb3SEric Fiselier#endif // _LIBCPP_COMPILER_MSVC
891c206366fSHoward Hinnant}
892c8edcb36SHoward Hinnant
89380f8cfb3SEric Fiselierinline _LIBCPP_INLINE_VISIBILITY int __pop_count(unsigned __x) {
89480f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
89580f8cfb3SEric Fiselier  return __builtin_popcount  (__x);
89680f8cfb3SEric Fiselier#else
89780f8cfb3SEric Fiselier  static_assert(sizeof(unsigned) == 4, "");
89880f8cfb3SEric Fiselier  return __popcnt(__x);
89980f8cfb3SEric Fiselier#endif
90080f8cfb3SEric Fiselier}
90180f8cfb3SEric Fiselier
90280f8cfb3SEric Fiselierinline _LIBCPP_INLINE_VISIBILITY int __pop_count(unsigned long __x) {
90380f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
90480f8cfb3SEric Fiselier  return __builtin_popcountl (__x);
90580f8cfb3SEric Fiselier#else
90680f8cfb3SEric Fiselier  static_assert(sizeof(unsigned long) == 4, "");
90780f8cfb3SEric Fiselier  return __popcnt(__x);
90880f8cfb3SEric Fiselier#endif
90980f8cfb3SEric Fiselier}
91080f8cfb3SEric Fiselier
91180f8cfb3SEric Fiselierinline _LIBCPP_INLINE_VISIBILITY int __pop_count(unsigned long long __x) {
91280f8cfb3SEric Fiselier#ifndef _LIBCPP_COMPILER_MSVC
91380f8cfb3SEric Fiselier  return __builtin_popcountll(__x);
91480f8cfb3SEric Fiselier#else
91580f8cfb3SEric Fiselier  static_assert(sizeof(unsigned long long) == 8, "");
91680f8cfb3SEric Fiselier  return __popcnt64(__x);
91780f8cfb3SEric Fiselier#endif
91880f8cfb3SEric Fiselier}
919c8edcb36SHoward Hinnant
9203e519524SHoward Hinnant// all_of
9213e519524SHoward Hinnant
9223e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
923706ffef7SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9243e519524SHoward Hinnantbool
9253e519524SHoward Hinnantall_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9263e519524SHoward Hinnant{
9273e519524SHoward Hinnant    for (; __first != __last; ++__first)
9283e519524SHoward Hinnant        if (!__pred(*__first))
9293e519524SHoward Hinnant            return false;
9303e519524SHoward Hinnant    return true;
9313e519524SHoward Hinnant}
9323e519524SHoward Hinnant
9333e519524SHoward Hinnant// any_of
9343e519524SHoward Hinnant
9353e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
936706ffef7SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9373e519524SHoward Hinnantbool
9383e519524SHoward Hinnantany_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9393e519524SHoward Hinnant{
9403e519524SHoward Hinnant    for (; __first != __last; ++__first)
9413e519524SHoward Hinnant        if (__pred(*__first))
9423e519524SHoward Hinnant            return true;
9433e519524SHoward Hinnant    return false;
9443e519524SHoward Hinnant}
9453e519524SHoward Hinnant
9463e519524SHoward Hinnant// none_of
9473e519524SHoward Hinnant
9483e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
949706ffef7SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9503e519524SHoward Hinnantbool
9513e519524SHoward Hinnantnone_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9523e519524SHoward Hinnant{
9533e519524SHoward Hinnant    for (; __first != __last; ++__first)
9543e519524SHoward Hinnant        if (__pred(*__first))
9553e519524SHoward Hinnant            return false;
9563e519524SHoward Hinnant    return true;
9573e519524SHoward Hinnant}
9583e519524SHoward Hinnant
9593e519524SHoward Hinnant// for_each
9603e519524SHoward Hinnant
9613e519524SHoward Hinnanttemplate <class _InputIterator, class _Function>
9621b9a4ffdSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9633e519524SHoward Hinnant_Function
9643e519524SHoward Hinnantfor_each(_InputIterator __first, _InputIterator __last, _Function __f)
9653e519524SHoward Hinnant{
9663e519524SHoward Hinnant    for (; __first != __last; ++__first)
9673e519524SHoward Hinnant        __f(*__first);
9681c7fe126SMarshall Clow    return __f;
9693e519524SHoward Hinnant}
9703e519524SHoward Hinnant
9711d02996dSMarshall Clow#if _LIBCPP_STD_VER > 14
972d5c65ffaSMarshall Clow// for_each_n
973d5c65ffaSMarshall Clow
974d5c65ffaSMarshall Clowtemplate <class _InputIterator, class _Size, class _Function>
9751b9a4ffdSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
976d5c65ffaSMarshall Clow_InputIterator
977d5c65ffaSMarshall Clowfor_each_n(_InputIterator __first, _Size __orig_n, _Function __f)
978d5c65ffaSMarshall Clow{
979d5c65ffaSMarshall Clow    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
980d5c65ffaSMarshall Clow    _IntegralSize __n = __orig_n;
981d5c65ffaSMarshall Clow    while (__n > 0)
982d5c65ffaSMarshall Clow    {
983d5c65ffaSMarshall Clow         __f(*__first);
984d5c65ffaSMarshall Clow         ++__first;
985d5c65ffaSMarshall Clow         --__n;
986d5c65ffaSMarshall Clow    }
987d5c65ffaSMarshall Clow    return __first;
988d5c65ffaSMarshall Clow}
9891d02996dSMarshall Clow#endif
990d5c65ffaSMarshall Clow
9913e519524SHoward Hinnant// find
9923e519524SHoward Hinnant
9933e519524SHoward Hinnanttemplate <class _InputIterator, class _Tp>
99449c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9953e519524SHoward Hinnant_InputIterator
996e4383379SHoward Hinnantfind(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
9973e519524SHoward Hinnant{
9983e519524SHoward Hinnant    for (; __first != __last; ++__first)
999e4383379SHoward Hinnant        if (*__first == __value_)
10003e519524SHoward Hinnant            break;
10013e519524SHoward Hinnant    return __first;
10023e519524SHoward Hinnant}
10033e519524SHoward Hinnant
10043e519524SHoward Hinnant// find_if
10053e519524SHoward Hinnant
10063e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
100749c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
10083e519524SHoward Hinnant_InputIterator
10093e519524SHoward Hinnantfind_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
10103e519524SHoward Hinnant{
10113e519524SHoward Hinnant    for (; __first != __last; ++__first)
10123e519524SHoward Hinnant        if (__pred(*__first))
10133e519524SHoward Hinnant            break;
10143e519524SHoward Hinnant    return __first;
10153e519524SHoward Hinnant}
10163e519524SHoward Hinnant
10173e519524SHoward Hinnant// find_if_not
10183e519524SHoward Hinnant
10193e519524SHoward Hinnanttemplate<class _InputIterator, class _Predicate>
10208694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
10213e519524SHoward Hinnant_InputIterator
10223e519524SHoward Hinnantfind_if_not(_InputIterator __first, _InputIterator __last, _Predicate __pred)
10233e519524SHoward Hinnant{
10243e519524SHoward Hinnant    for (; __first != __last; ++__first)
10253e519524SHoward Hinnant        if (!__pred(*__first))
10263e519524SHoward Hinnant            break;
10273e519524SHoward Hinnant    return __first;
10283e519524SHoward Hinnant}
10293e519524SHoward Hinnant
10303e519524SHoward Hinnant// find_end
10313e519524SHoward Hinnant
10323e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
10338694428eSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
10343e519524SHoward Hinnant__find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
10353e519524SHoward Hinnant           _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
10363e519524SHoward Hinnant           forward_iterator_tag, forward_iterator_tag)
10373e519524SHoward Hinnant{
10383e519524SHoward Hinnant    // modeled after search algorithm
10393e519524SHoward Hinnant    _ForwardIterator1 __r = __last1;  // __last1 is the "default" answer
10403e519524SHoward Hinnant    if (__first2 == __last2)
10413e519524SHoward Hinnant        return __r;
10423e519524SHoward Hinnant    while (true)
10433e519524SHoward Hinnant    {
10443e519524SHoward Hinnant        while (true)
10453e519524SHoward Hinnant        {
10463e519524SHoward Hinnant            if (__first1 == __last1)         // if source exhausted return last correct answer
10473e519524SHoward Hinnant                return __r;                  //    (or __last1 if never found)
10483e519524SHoward Hinnant            if (__pred(*__first1, *__first2))
10493e519524SHoward Hinnant                break;
10503e519524SHoward Hinnant            ++__first1;
10513e519524SHoward Hinnant        }
10523e519524SHoward Hinnant        // *__first1 matches *__first2, now match elements after here
10533e519524SHoward Hinnant        _ForwardIterator1 __m1 = __first1;
10543e519524SHoward Hinnant        _ForwardIterator2 __m2 = __first2;
10553e519524SHoward Hinnant        while (true)
10563e519524SHoward Hinnant        {
10573e519524SHoward Hinnant            if (++__m2 == __last2)
10583e519524SHoward Hinnant            {                         // Pattern exhaused, record answer and search for another one
10593e519524SHoward Hinnant                __r = __first1;
10603e519524SHoward Hinnant                ++__first1;
10613e519524SHoward Hinnant                break;
10623e519524SHoward Hinnant            }
10633e519524SHoward Hinnant            if (++__m1 == __last1)     // Source exhausted, return last answer
10643e519524SHoward Hinnant                return __r;
10653e519524SHoward Hinnant            if (!__pred(*__m1, *__m2))  // mismatch, restart with a new __first
10663e519524SHoward Hinnant            {
10673e519524SHoward Hinnant                ++__first1;
10683e519524SHoward Hinnant                break;
10693e519524SHoward Hinnant            }  // else there is a match, check next elements
10703e519524SHoward Hinnant        }
10713e519524SHoward Hinnant    }
10723e519524SHoward Hinnant}
10733e519524SHoward Hinnant
10743e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _BidirectionalIterator1, class _BidirectionalIterator2>
10758694428eSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator1
10763e519524SHoward Hinnant__find_end(_BidirectionalIterator1 __first1, _BidirectionalIterator1 __last1,
10773e519524SHoward Hinnant           _BidirectionalIterator2 __first2, _BidirectionalIterator2 __last2, _BinaryPredicate __pred,
10783e519524SHoward Hinnant           bidirectional_iterator_tag, bidirectional_iterator_tag)
10793e519524SHoward Hinnant{
10803e519524SHoward Hinnant    // modeled after search algorithm (in reverse)
10813e519524SHoward Hinnant    if (__first2 == __last2)
10823e519524SHoward Hinnant        return __last1;  // Everything matches an empty sequence
10833e519524SHoward Hinnant    _BidirectionalIterator1 __l1 = __last1;
10843e519524SHoward Hinnant    _BidirectionalIterator2 __l2 = __last2;
10853e519524SHoward Hinnant    --__l2;
10863e519524SHoward Hinnant    while (true)
10873e519524SHoward Hinnant    {
10883e519524SHoward Hinnant        // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
10893e519524SHoward Hinnant        while (true)
10903e519524SHoward Hinnant        {
10913e519524SHoward Hinnant            if (__first1 == __l1)  // return __last1 if no element matches *__first2
10923e519524SHoward Hinnant                return __last1;
10933e519524SHoward Hinnant            if (__pred(*--__l1, *__l2))
10943e519524SHoward Hinnant                break;
10953e519524SHoward Hinnant        }
10963e519524SHoward Hinnant        // *__l1 matches *__l2, now match elements before here
10973e519524SHoward Hinnant        _BidirectionalIterator1 __m1 = __l1;
10983e519524SHoward Hinnant        _BidirectionalIterator2 __m2 = __l2;
10993e519524SHoward Hinnant        while (true)
11003e519524SHoward Hinnant        {
11013e519524SHoward Hinnant            if (__m2 == __first2)  // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
11023e519524SHoward Hinnant                return __m1;
11033e519524SHoward Hinnant            if (__m1 == __first1)  // Otherwise if source exhaused, pattern not found
11043e519524SHoward Hinnant                return __last1;
11053e519524SHoward Hinnant            if (!__pred(*--__m1, *--__m2))  // if there is a mismatch, restart with a new __l1
11063e519524SHoward Hinnant            {
11073e519524SHoward Hinnant                break;
11083e519524SHoward Hinnant            }  // else there is a match, check next elements
11093e519524SHoward Hinnant        }
11103e519524SHoward Hinnant    }
11113e519524SHoward Hinnant}
11123e519524SHoward Hinnant
11133e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
11149b0af34dSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1
11153e519524SHoward Hinnant__find_end(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
11163e519524SHoward Hinnant           _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
11173e519524SHoward Hinnant           random_access_iterator_tag, random_access_iterator_tag)
11183e519524SHoward Hinnant{
11193e519524SHoward Hinnant    // Take advantage of knowing source and pattern lengths.  Stop short when source is smaller than pattern
11203e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator2>::difference_type __len2 = __last2 - __first2;
11213e519524SHoward Hinnant    if (__len2 == 0)
11223e519524SHoward Hinnant        return __last1;
11233e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator1>::difference_type __len1 = __last1 - __first1;
11243e519524SHoward Hinnant    if (__len1 < __len2)
11253e519524SHoward Hinnant        return __last1;
11263e519524SHoward Hinnant    const _RandomAccessIterator1 __s = __first1 + (__len2 - 1);  // End of pattern match can't go before here
11273e519524SHoward Hinnant    _RandomAccessIterator1 __l1 = __last1;
11283e519524SHoward Hinnant    _RandomAccessIterator2 __l2 = __last2;
11293e519524SHoward Hinnant    --__l2;
11303e519524SHoward Hinnant    while (true)
11313e519524SHoward Hinnant    {
11323e519524SHoward Hinnant        while (true)
11333e519524SHoward Hinnant        {
11343e519524SHoward Hinnant            if (__s == __l1)
11353e519524SHoward Hinnant                return __last1;
11363e519524SHoward Hinnant            if (__pred(*--__l1, *__l2))
11373e519524SHoward Hinnant                break;
11383e519524SHoward Hinnant        }
11393e519524SHoward Hinnant        _RandomAccessIterator1 __m1 = __l1;
11403e519524SHoward Hinnant        _RandomAccessIterator2 __m2 = __l2;
11413e519524SHoward Hinnant        while (true)
11423e519524SHoward Hinnant        {
11433e519524SHoward Hinnant            if (__m2 == __first2)
11443e519524SHoward Hinnant                return __m1;
11453e519524SHoward Hinnant                                 // no need to check range on __m1 because __s guarantees we have enough source
11463e519524SHoward Hinnant            if (!__pred(*--__m1, *--__m2))
11473e519524SHoward Hinnant            {
11483e519524SHoward Hinnant                break;
11493e519524SHoward Hinnant            }
11503e519524SHoward Hinnant        }
11513e519524SHoward Hinnant    }
11523e519524SHoward Hinnant}
11533e519524SHoward Hinnant
11543e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11558694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11563e519524SHoward Hinnant_ForwardIterator1
11573e519524SHoward Hinnantfind_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11583e519524SHoward Hinnant         _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11593e519524SHoward Hinnant{
1160ce48a113SHoward Hinnant    return _VSTD::__find_end<typename add_lvalue_reference<_BinaryPredicate>::type>
11613e519524SHoward Hinnant                         (__first1, __last1, __first2, __last2, __pred,
11623e519524SHoward Hinnant                          typename iterator_traits<_ForwardIterator1>::iterator_category(),
11633e519524SHoward Hinnant                          typename iterator_traits<_ForwardIterator2>::iterator_category());
11643e519524SHoward Hinnant}
11653e519524SHoward Hinnant
11663e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2>
11678694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11683e519524SHoward Hinnant_ForwardIterator1
11693e519524SHoward Hinnantfind_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11703e519524SHoward Hinnant         _ForwardIterator2 __first2, _ForwardIterator2 __last2)
11713e519524SHoward Hinnant{
11723e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
11733e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1174ce48a113SHoward Hinnant    return _VSTD::find_end(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
11753e519524SHoward Hinnant}
11763e519524SHoward Hinnant
11773e519524SHoward Hinnant// find_first_of
11783e519524SHoward Hinnant
11793e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11809b0af34dSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator1
11819b0af34dSMarshall Clow__find_first_of_ce(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11823e519524SHoward Hinnant              _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11833e519524SHoward Hinnant{
11843e519524SHoward Hinnant    for (; __first1 != __last1; ++__first1)
11853e519524SHoward Hinnant        for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
11863e519524SHoward Hinnant            if (__pred(*__first1, *__j))
11873e519524SHoward Hinnant                return __first1;
11883e519524SHoward Hinnant    return __last1;
11893e519524SHoward Hinnant}
11903e519524SHoward Hinnant
11919b0af34dSMarshall Clow
11929b0af34dSMarshall Clowtemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11938694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY  _LIBCPP_CONSTEXPR_AFTER_CXX17
11949b0af34dSMarshall Clow_ForwardIterator1
11959b0af34dSMarshall Clowfind_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11969b0af34dSMarshall Clow              _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11979b0af34dSMarshall Clow{
11989b0af34dSMarshall Clow    return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __pred);
11999b0af34dSMarshall Clow}
12009b0af34dSMarshall Clow
12013e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2>
12028694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY  _LIBCPP_CONSTEXPR_AFTER_CXX17
12033e519524SHoward Hinnant_ForwardIterator1
12043e519524SHoward Hinnantfind_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
12053e519524SHoward Hinnant              _ForwardIterator2 __first2, _ForwardIterator2 __last2)
12063e519524SHoward Hinnant{
12073e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
12083e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
12099b0af34dSMarshall Clow    return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
12103e519524SHoward Hinnant}
12113e519524SHoward Hinnant
12123e519524SHoward Hinnant// adjacent_find
12133e519524SHoward Hinnant
12143e519524SHoward Hinnanttemplate <class _ForwardIterator, class _BinaryPredicate>
12158694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12163e519524SHoward Hinnant_ForwardIterator
12173e519524SHoward Hinnantadjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
12183e519524SHoward Hinnant{
12193e519524SHoward Hinnant    if (__first != __last)
12203e519524SHoward Hinnant    {
12213e519524SHoward Hinnant        _ForwardIterator __i = __first;
12223e519524SHoward Hinnant        while (++__i != __last)
12233e519524SHoward Hinnant        {
12243e519524SHoward Hinnant            if (__pred(*__first, *__i))
12253e519524SHoward Hinnant                return __first;
12263e519524SHoward Hinnant            __first = __i;
12273e519524SHoward Hinnant        }
12283e519524SHoward Hinnant    }
12293e519524SHoward Hinnant    return __last;
12303e519524SHoward Hinnant}
12313e519524SHoward Hinnant
12323e519524SHoward Hinnanttemplate <class _ForwardIterator>
12338694428eSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12343e519524SHoward Hinnant_ForwardIterator
12353e519524SHoward Hinnantadjacent_find(_ForwardIterator __first, _ForwardIterator __last)
12363e519524SHoward Hinnant{
12373e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
1238ce48a113SHoward Hinnant    return _VSTD::adjacent_find(__first, __last, __equal_to<__v>());
12393e519524SHoward Hinnant}
12403e519524SHoward Hinnant
12413e519524SHoward Hinnant// count
12423e519524SHoward Hinnant
12433e519524SHoward Hinnanttemplate <class _InputIterator, class _Tp>
1244056f15e3SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12453e519524SHoward Hinnanttypename iterator_traits<_InputIterator>::difference_type
1246e4383379SHoward Hinnantcount(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
12473e519524SHoward Hinnant{
12483e519524SHoward Hinnant    typename iterator_traits<_InputIterator>::difference_type __r(0);
12493e519524SHoward Hinnant    for (; __first != __last; ++__first)
1250e4383379SHoward Hinnant        if (*__first == __value_)
12513e519524SHoward Hinnant            ++__r;
12523e519524SHoward Hinnant    return __r;
12533e519524SHoward Hinnant}
12543e519524SHoward Hinnant
12553e519524SHoward Hinnant// count_if
12563e519524SHoward Hinnant
12573e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
1258056f15e3SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12593e519524SHoward Hinnanttypename iterator_traits<_InputIterator>::difference_type
12603e519524SHoward Hinnantcount_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
12613e519524SHoward Hinnant{
12623e519524SHoward Hinnant    typename iterator_traits<_InputIterator>::difference_type __r(0);
12633e519524SHoward Hinnant    for (; __first != __last; ++__first)
12643e519524SHoward Hinnant        if (__pred(*__first))
12653e519524SHoward Hinnant            ++__r;
12663e519524SHoward Hinnant    return __r;
12673e519524SHoward Hinnant}
12683e519524SHoward Hinnant
12693e519524SHoward Hinnant// mismatch
12703e519524SHoward Hinnant
12713e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12726538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12733e519524SHoward Hinnantpair<_InputIterator1, _InputIterator2>
12743e519524SHoward Hinnantmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12753e519524SHoward Hinnant         _InputIterator2 __first2, _BinaryPredicate __pred)
12763e519524SHoward Hinnant{
1277bd7c7b55SMarshall Clow    for (; __first1 != __last1; ++__first1, (void) ++__first2)
12783e519524SHoward Hinnant        if (!__pred(*__first1, *__first2))
12793e519524SHoward Hinnant            break;
12803e519524SHoward Hinnant    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
12813e519524SHoward Hinnant}
12823e519524SHoward Hinnant
12833e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
12846538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12853e519524SHoward Hinnantpair<_InputIterator1, _InputIterator2>
12863e519524SHoward Hinnantmismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
12873e519524SHoward Hinnant{
12883e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12893e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1290ce48a113SHoward Hinnant    return _VSTD::mismatch(__first1, __last1, __first2, __equal_to<__v1, __v2>());
12913e519524SHoward Hinnant}
12923e519524SHoward Hinnant
12930b0bbd2fSMarshall Clow#if _LIBCPP_STD_VER > 11
12940b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12956538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12960b0bbd2fSMarshall Clowpair<_InputIterator1, _InputIterator2>
12970b0bbd2fSMarshall Clowmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12980b0bbd2fSMarshall Clow         _InputIterator2 __first2, _InputIterator2 __last2,
12990b0bbd2fSMarshall Clow         _BinaryPredicate __pred)
13000b0bbd2fSMarshall Clow{
1301bd7c7b55SMarshall Clow    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
13020b0bbd2fSMarshall Clow        if (!__pred(*__first1, *__first2))
13030b0bbd2fSMarshall Clow            break;
13040b0bbd2fSMarshall Clow    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
13050b0bbd2fSMarshall Clow}
13060b0bbd2fSMarshall Clow
13070b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2>
13086538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13090b0bbd2fSMarshall Clowpair<_InputIterator1, _InputIterator2>
13100b0bbd2fSMarshall Clowmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
13110b0bbd2fSMarshall Clow         _InputIterator2 __first2, _InputIterator2 __last2)
13120b0bbd2fSMarshall Clow{
13130b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
13140b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
13150b0bbd2fSMarshall Clow    return _VSTD::mismatch(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
13160b0bbd2fSMarshall Clow}
13170b0bbd2fSMarshall Clow#endif
13180b0bbd2fSMarshall Clow
13193e519524SHoward Hinnant// equal
13203e519524SHoward Hinnant
13213e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
13226538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13233e519524SHoward Hinnantbool
13243e519524SHoward Hinnantequal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred)
13253e519524SHoward Hinnant{
1326910285b2SEric Fiselier    for (; __first1 != __last1; ++__first1, (void) ++__first2)
13273e519524SHoward Hinnant        if (!__pred(*__first1, *__first2))
13283e519524SHoward Hinnant            return false;
13293e519524SHoward Hinnant    return true;
13303e519524SHoward Hinnant}
13313e519524SHoward Hinnant
13323e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
13336538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13343e519524SHoward Hinnantbool
13353e519524SHoward Hinnantequal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
13363e519524SHoward Hinnant{
13373e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
13383e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1339ce48a113SHoward Hinnant    return _VSTD::equal(__first1, __last1, __first2, __equal_to<__v1, __v2>());
13403e519524SHoward Hinnant}
13413e519524SHoward Hinnant
13420b0bbd2fSMarshall Clow#if _LIBCPP_STD_VER > 11
13430b0bbd2fSMarshall Clowtemplate <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
13446538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13450b0bbd2fSMarshall Clowbool
13460b0bbd2fSMarshall Clow__equal(_InputIterator1 __first1, _InputIterator1 __last1,
13470b0bbd2fSMarshall Clow        _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred,
13480b0bbd2fSMarshall Clow        input_iterator_tag, input_iterator_tag )
13490b0bbd2fSMarshall Clow{
1350910285b2SEric Fiselier    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
13510b0bbd2fSMarshall Clow        if (!__pred(*__first1, *__first2))
13520b0bbd2fSMarshall Clow            return false;
13530b0bbd2fSMarshall Clow    return __first1 == __last1 && __first2 == __last2;
13540b0bbd2fSMarshall Clow}
13550b0bbd2fSMarshall Clow
13560b0bbd2fSMarshall Clowtemplate <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
13576538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13580b0bbd2fSMarshall Clowbool
13590b0bbd2fSMarshall Clow__equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
13600b0bbd2fSMarshall Clow        _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
13610b0bbd2fSMarshall Clow      random_access_iterator_tag, random_access_iterator_tag )
13620b0bbd2fSMarshall Clow{
13630b0bbd2fSMarshall Clow    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
13640b0bbd2fSMarshall Clow        return false;
13650b0bbd2fSMarshall Clow    return _VSTD::equal<_RandomAccessIterator1, _RandomAccessIterator2,
13660b0bbd2fSMarshall Clow                        typename add_lvalue_reference<_BinaryPredicate>::type>
13670b0bbd2fSMarshall Clow                       (__first1, __last1, __first2, __pred );
13680b0bbd2fSMarshall Clow}
13690b0bbd2fSMarshall Clow
13700b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
13716538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13720b0bbd2fSMarshall Clowbool
13730b0bbd2fSMarshall Clowequal(_InputIterator1 __first1, _InputIterator1 __last1,
13740b0bbd2fSMarshall Clow      _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred )
13750b0bbd2fSMarshall Clow{
13760b0bbd2fSMarshall Clow    return _VSTD::__equal<typename add_lvalue_reference<_BinaryPredicate>::type>
13770b0bbd2fSMarshall Clow       (__first1, __last1, __first2, __last2, __pred,
13780b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator1>::iterator_category(),
13790b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator2>::iterator_category());
13800b0bbd2fSMarshall Clow}
13810b0bbd2fSMarshall Clow
13820b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2>
13836538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13840b0bbd2fSMarshall Clowbool
13850b0bbd2fSMarshall Clowequal(_InputIterator1 __first1, _InputIterator1 __last1,
13860b0bbd2fSMarshall Clow      _InputIterator2 __first2, _InputIterator2 __last2)
13870b0bbd2fSMarshall Clow{
13880b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
13890b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
13900b0bbd2fSMarshall Clow    return _VSTD::__equal(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>(),
13910b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator1>::iterator_category(),
13920b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator2>::iterator_category());
13930b0bbd2fSMarshall Clow}
13940b0bbd2fSMarshall Clow#endif
13950b0bbd2fSMarshall Clow
13963e519524SHoward Hinnant// is_permutation
13973e519524SHoward Hinnant
13983e519524SHoward Hinnanttemplate<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
139949c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
14003e519524SHoward Hinnantis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14013e519524SHoward Hinnant               _ForwardIterator2 __first2, _BinaryPredicate __pred)
14023e519524SHoward Hinnant{
140349c7643cSMarshall Clow//  shorten sequences as much as possible by lopping of any equal prefix
1404910285b2SEric Fiselier    for (; __first1 != __last1; ++__first1, (void) ++__first2)
14053e519524SHoward Hinnant        if (!__pred(*__first1, *__first2))
140649c7643cSMarshall Clow            break;
140749c7643cSMarshall Clow    if (__first1 == __last1)
14083e519524SHoward Hinnant        return true;
140949c7643cSMarshall Clow
14103e519524SHoward Hinnant//  __first1 != __last1 && *__first1 != *__first2
14113e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
1412ce48a113SHoward Hinnant    _D1 __l1 = _VSTD::distance(__first1, __last1);
14133e519524SHoward Hinnant    if (__l1 == _D1(1))
14143e519524SHoward Hinnant        return false;
1415ce48a113SHoward Hinnant    _ForwardIterator2 __last2 = _VSTD::next(__first2, __l1);
14163e519524SHoward Hinnant    // For each element in [f1, l1) see if there are the same number of
14173e519524SHoward Hinnant    //    equal elements in [f2, l2)
14183e519524SHoward Hinnant    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
14193e519524SHoward Hinnant    {
14203e519524SHoward Hinnant    //  Have we already counted the number of *__i in [f1, l1)?
142149c7643cSMarshall Clow        if (find(__first1, __i, *__i) == __i) {
14223e519524SHoward Hinnant            // Count number of *__i in [f2, l2)
14233e519524SHoward Hinnant            _D1 __c2 = 0;
14243e519524SHoward Hinnant            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
14253e519524SHoward Hinnant                if (__pred(*__i, *__j))
14263e519524SHoward Hinnant                    ++__c2;
14273e519524SHoward Hinnant            if (__c2 == 0)
14283e519524SHoward Hinnant                return false;
14293e519524SHoward Hinnant            // Count number of *__i in [__i, l1) (we can start with 1)
14303e519524SHoward Hinnant            _D1 __c1 = 1;
1431ce48a113SHoward Hinnant            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
14323e519524SHoward Hinnant                if (__pred(*__i, *__j))
14333e519524SHoward Hinnant                    ++__c1;
14343e519524SHoward Hinnant            if (__c1 != __c2)
14353e519524SHoward Hinnant                return false;
14363e519524SHoward Hinnant        }
14373e519524SHoward Hinnant    }
14383e519524SHoward Hinnant    return true;
14393e519524SHoward Hinnant}
14403e519524SHoward Hinnant
14413e519524SHoward Hinnanttemplate<class _ForwardIterator1, class _ForwardIterator2>
144249c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14433e519524SHoward Hinnantbool
14443e519524SHoward Hinnantis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14453e519524SHoward Hinnant               _ForwardIterator2 __first2)
14463e519524SHoward Hinnant{
14473e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
14483e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1449ce48a113SHoward Hinnant    return _VSTD::is_permutation(__first1, __last1, __first2, __equal_to<__v1, __v2>());
14503e519524SHoward Hinnant}
14513e519524SHoward Hinnant
14520b0bbd2fSMarshall Clow#if _LIBCPP_STD_VER > 11
14530b0bbd2fSMarshall Clowtemplate<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
145449c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
14550b0bbd2fSMarshall Clow__is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14560b0bbd2fSMarshall Clow                 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
14570b0bbd2fSMarshall Clow                 _BinaryPredicate __pred,
14580b0bbd2fSMarshall Clow                 forward_iterator_tag, forward_iterator_tag )
14590b0bbd2fSMarshall Clow{
146049c7643cSMarshall Clow//  shorten sequences as much as possible by lopping of any equal prefix
1461847ee131SEric Fiselier    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
14620b0bbd2fSMarshall Clow        if (!__pred(*__first1, *__first2))
146349c7643cSMarshall Clow            break;
146449c7643cSMarshall Clow    if (__first1 == __last1)
146549c7643cSMarshall Clow        return __first2 == __last2;
146649c7643cSMarshall Clow    else if (__first2 == __last2)
146749c7643cSMarshall Clow        return false;
146849c7643cSMarshall Clow
14690b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
14700b0bbd2fSMarshall Clow    _D1 __l1 = _VSTD::distance(__first1, __last1);
14710b0bbd2fSMarshall Clow
14720b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator2>::difference_type _D2;
1473fce85ba4SMarshall Clow    _D2 __l2 = _VSTD::distance(__first2, __last2);
14740b0bbd2fSMarshall Clow    if (__l1 != __l2)
14750b0bbd2fSMarshall Clow        return false;
14760b0bbd2fSMarshall Clow
14770b0bbd2fSMarshall Clow    // For each element in [f1, l1) see if there are the same number of
14780b0bbd2fSMarshall Clow    //    equal elements in [f2, l2)
14790b0bbd2fSMarshall Clow    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
14800b0bbd2fSMarshall Clow    {
14810b0bbd2fSMarshall Clow    //  Have we already counted the number of *__i in [f1, l1)?
148249c7643cSMarshall Clow        if (find(__first1, __i, *__i) == __i) {
14830b0bbd2fSMarshall Clow            // Count number of *__i in [f2, l2)
14840b0bbd2fSMarshall Clow            _D1 __c2 = 0;
14850b0bbd2fSMarshall Clow            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
14860b0bbd2fSMarshall Clow                if (__pred(*__i, *__j))
14870b0bbd2fSMarshall Clow                    ++__c2;
14880b0bbd2fSMarshall Clow            if (__c2 == 0)
14890b0bbd2fSMarshall Clow                return false;
14900b0bbd2fSMarshall Clow            // Count number of *__i in [__i, l1) (we can start with 1)
14910b0bbd2fSMarshall Clow            _D1 __c1 = 1;
14920b0bbd2fSMarshall Clow            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
14930b0bbd2fSMarshall Clow                if (__pred(*__i, *__j))
14940b0bbd2fSMarshall Clow                    ++__c1;
14950b0bbd2fSMarshall Clow            if (__c1 != __c2)
14960b0bbd2fSMarshall Clow                return false;
14970b0bbd2fSMarshall Clow        }
14980b0bbd2fSMarshall Clow    }
14990b0bbd2fSMarshall Clow    return true;
15000b0bbd2fSMarshall Clow}
15010b0bbd2fSMarshall Clow
15020b0bbd2fSMarshall Clowtemplate<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
150349c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
15040b0bbd2fSMarshall Clow__is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
15050b0bbd2fSMarshall Clow               _RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2,
15060b0bbd2fSMarshall Clow               _BinaryPredicate __pred,
15070b0bbd2fSMarshall Clow               random_access_iterator_tag, random_access_iterator_tag )
15080b0bbd2fSMarshall Clow{
15090b0bbd2fSMarshall Clow    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
15100b0bbd2fSMarshall Clow        return false;
15110b0bbd2fSMarshall Clow    return _VSTD::is_permutation<_RandomAccessIterator1, _RandomAccessIterator2,
15120b0bbd2fSMarshall Clow                                 typename add_lvalue_reference<_BinaryPredicate>::type>
15130b0bbd2fSMarshall Clow                                (__first1, __last1, __first2, __pred );
15140b0bbd2fSMarshall Clow}
15150b0bbd2fSMarshall Clow
15160b0bbd2fSMarshall Clowtemplate<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
151749c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15180b0bbd2fSMarshall Clowbool
15190b0bbd2fSMarshall Clowis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15200b0bbd2fSMarshall Clow               _ForwardIterator2 __first2, _ForwardIterator2 __last2,
15210b0bbd2fSMarshall Clow               _BinaryPredicate __pred )
15220b0bbd2fSMarshall Clow{
15230b0bbd2fSMarshall Clow    return _VSTD::__is_permutation<typename add_lvalue_reference<_BinaryPredicate>::type>
15240b0bbd2fSMarshall Clow       (__first1, __last1, __first2, __last2, __pred,
15250b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator1>::iterator_category(),
15260b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator2>::iterator_category());
15270b0bbd2fSMarshall Clow}
15280b0bbd2fSMarshall Clow
15290b0bbd2fSMarshall Clowtemplate<class _ForwardIterator1, class _ForwardIterator2>
153049c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15310b0bbd2fSMarshall Clowbool
15320b0bbd2fSMarshall Clowis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15330b0bbd2fSMarshall Clow               _ForwardIterator2 __first2, _ForwardIterator2 __last2)
15340b0bbd2fSMarshall Clow{
15350b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
15360b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
15370b0bbd2fSMarshall Clow    return _VSTD::__is_permutation(__first1, __last1, __first2, __last2,
15380b0bbd2fSMarshall Clow        __equal_to<__v1, __v2>(),
15390b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator1>::iterator_category(),
15400b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator2>::iterator_category());
15410b0bbd2fSMarshall Clow}
15420b0bbd2fSMarshall Clow#endif
15430b0bbd2fSMarshall Clow
15443e519524SHoward Hinnant// search
1545d835e592SMarshall Clow// __search is in <functional>
15463e519524SHoward Hinnant
15473e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
154812f0a779SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15493e519524SHoward Hinnant_ForwardIterator1
15503e519524SHoward Hinnantsearch(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15513e519524SHoward Hinnant       _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
15523e519524SHoward Hinnant{
1553ce48a113SHoward Hinnant    return _VSTD::__search<typename add_lvalue_reference<_BinaryPredicate>::type>
15543e519524SHoward Hinnant                         (__first1, __last1, __first2, __last2, __pred,
155528cc4ddeSMarshall Clow                          typename iterator_traits<_ForwardIterator1>::iterator_category(),
155628cc4ddeSMarshall Clow                          typename iterator_traits<_ForwardIterator2>::iterator_category())
155728cc4ddeSMarshall Clow            .first;
15583e519524SHoward Hinnant}
15593e519524SHoward Hinnant
15603e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2>
156112f0a779SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15623e519524SHoward Hinnant_ForwardIterator1
15633e519524SHoward Hinnantsearch(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15643e519524SHoward Hinnant       _ForwardIterator2 __first2, _ForwardIterator2 __last2)
15653e519524SHoward Hinnant{
156628cc4ddeSMarshall Clow    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
156728cc4ddeSMarshall Clow    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1568ce48a113SHoward Hinnant    return _VSTD::search(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
15693e519524SHoward Hinnant}
15703e519524SHoward Hinnant
1571d835e592SMarshall Clow
1572d835e592SMarshall Clow#if _LIBCPP_STD_VER > 14
1573d835e592SMarshall Clowtemplate <class _ForwardIterator, class _Searcher>
157412f0a779SMarshall Clow_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1575d835e592SMarshall Clow_ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
1576d835e592SMarshall Clow{ return __s(__f, __l).first; }
1577d835e592SMarshall Clow#endif
1578d835e592SMarshall Clow
15793e519524SHoward Hinnant// search_n
15803e519524SHoward Hinnant
15813e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _ForwardIterator, class _Size, class _Tp>
158212f0a779SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
15833e519524SHoward Hinnant__search_n(_ForwardIterator __first, _ForwardIterator __last,
1584e4383379SHoward Hinnant           _Size __count, const _Tp& __value_, _BinaryPredicate __pred, forward_iterator_tag)
15853e519524SHoward Hinnant{
15863e519524SHoward Hinnant    if (__count <= 0)
15873e519524SHoward Hinnant        return __first;
15883e519524SHoward Hinnant    while (true)
15893e519524SHoward Hinnant    {
1590e4383379SHoward Hinnant        // Find first element in sequence that matchs __value_, with a mininum of loop checks
15913e519524SHoward Hinnant        while (true)
15923e519524SHoward Hinnant        {
1593e4383379SHoward Hinnant            if (__first == __last)  // return __last if no element matches __value_
15943e519524SHoward Hinnant                return __last;
1595e4383379SHoward Hinnant            if (__pred(*__first, __value_))
15963e519524SHoward Hinnant                break;
15973e519524SHoward Hinnant            ++__first;
15983e519524SHoward Hinnant        }
1599e4383379SHoward Hinnant        // *__first matches __value_, now match elements after here
16003e519524SHoward Hinnant        _ForwardIterator __m = __first;
16013e519524SHoward Hinnant        _Size __c(0);
16023e519524SHoward Hinnant        while (true)
16033e519524SHoward Hinnant        {
16043e519524SHoward Hinnant            if (++__c == __count)  // If pattern exhausted, __first is the answer (works for 1 element pattern)
16053e519524SHoward Hinnant                return __first;
16063e519524SHoward Hinnant            if (++__m == __last)  // Otherwise if source exhaused, pattern not found
16073e519524SHoward Hinnant                return __last;
1608e4383379SHoward Hinnant            if (!__pred(*__m, __value_))  // if there is a mismatch, restart with a new __first
16093e519524SHoward Hinnant            {
16103e519524SHoward Hinnant                __first = __m;
16113e519524SHoward Hinnant                ++__first;
16123e519524SHoward Hinnant                break;
16133e519524SHoward Hinnant            }  // else there is a match, check next elements
16143e519524SHoward Hinnant        }
16153e519524SHoward Hinnant    }
16163e519524SHoward Hinnant}
16173e519524SHoward Hinnant
16183e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _RandomAccessIterator, class _Size, class _Tp>
161912f0a779SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
16203e519524SHoward Hinnant__search_n(_RandomAccessIterator __first, _RandomAccessIterator __last,
1621e4383379SHoward Hinnant           _Size __count, const _Tp& __value_, _BinaryPredicate __pred, random_access_iterator_tag)
16223e519524SHoward Hinnant{
16233e519524SHoward Hinnant    if (__count <= 0)
16243e519524SHoward Hinnant        return __first;
16253e519524SHoward Hinnant    _Size __len = static_cast<_Size>(__last - __first);
16263e519524SHoward Hinnant    if (__len < __count)
16273e519524SHoward Hinnant        return __last;
16283e519524SHoward Hinnant    const _RandomAccessIterator __s = __last - (__count - 1);  // Start of pattern match can't go beyond here
16293e519524SHoward Hinnant    while (true)
16303e519524SHoward Hinnant    {
1631e4383379SHoward Hinnant        // Find first element in sequence that matchs __value_, with a mininum of loop checks
16323e519524SHoward Hinnant        while (true)
16333e519524SHoward Hinnant        {
1634b13fcad6SHoward Hinnant            if (__first >= __s)  // return __last if no element matches __value_
16353e519524SHoward Hinnant                return __last;
1636e4383379SHoward Hinnant            if (__pred(*__first, __value_))
16373e519524SHoward Hinnant                break;
16383e519524SHoward Hinnant            ++__first;
16393e519524SHoward Hinnant        }
1640e4383379SHoward Hinnant        // *__first matches __value_, now match elements after here
16413e519524SHoward Hinnant        _RandomAccessIterator __m = __first;
16423e519524SHoward Hinnant        _Size __c(0);
16433e519524SHoward Hinnant        while (true)
16443e519524SHoward Hinnant        {
16453e519524SHoward Hinnant            if (++__c == __count)  // If pattern exhausted, __first is the answer (works for 1 element pattern)
16463e519524SHoward Hinnant                return __first;
16473e519524SHoward Hinnant             ++__m;          // no need to check range on __m because __s guarantees we have enough source
1648e4383379SHoward Hinnant            if (!__pred(*__m, __value_))  // if there is a mismatch, restart with a new __first
16493e519524SHoward Hinnant            {
16503e519524SHoward Hinnant                __first = __m;
16513e519524SHoward Hinnant                ++__first;
16523e519524SHoward Hinnant                break;
16533e519524SHoward Hinnant            }  // else there is a match, check next elements
16543e519524SHoward Hinnant        }
16553e519524SHoward Hinnant    }
16563e519524SHoward Hinnant}
16573e519524SHoward Hinnant
16583e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
165912f0a779SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
16603e519524SHoward Hinnant_ForwardIterator
16613e519524SHoward Hinnantsearch_n(_ForwardIterator __first, _ForwardIterator __last,
1662e4383379SHoward Hinnant         _Size __count, const _Tp& __value_, _BinaryPredicate __pred)
16633e519524SHoward Hinnant{
1664ce48a113SHoward Hinnant    return _VSTD::__search_n<typename add_lvalue_reference<_BinaryPredicate>::type>
166551544023SEric Fiselier           (__first, __last, __convert_to_integral(__count), __value_, __pred,
166651544023SEric Fiselier           typename iterator_traits<_ForwardIterator>::iterator_category());
16673e519524SHoward Hinnant}
16683e519524SHoward Hinnant
16693e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Size, class _Tp>
167012f0a779SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
16713e519524SHoward Hinnant_ForwardIterator
1672e4383379SHoward Hinnantsearch_n(_ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value_)
16733e519524SHoward Hinnant{
16743e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
167551544023SEric Fiselier    return _VSTD::search_n(__first, __last, __convert_to_integral(__count),
167651544023SEric Fiselier                           __value_, __equal_to<__v, _Tp>());
16773e519524SHoward Hinnant}
16783e519524SHoward Hinnant
16793e519524SHoward Hinnant// copy
16803e519524SHoward Hinnanttemplate <class _Iter>
16813e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
16823e519524SHoward Hinnant_Iter
16833e519524SHoward Hinnant__unwrap_iter(_Iter __i)
16843e519524SHoward Hinnant{
16853e519524SHoward Hinnant    return __i;
16863e519524SHoward Hinnant}
16873e519524SHoward Hinnant
16883e519524SHoward Hinnanttemplate <class _Tp>
16895b7c98e5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY
16903e519524SHoward Hinnanttypename enable_if
16913e519524SHoward Hinnant<
1692ca740483SHoward Hinnant    is_trivially_copy_assignable<_Tp>::value,
16933e519524SHoward Hinnant    _Tp*
16943e519524SHoward Hinnant>::type
16953e519524SHoward Hinnant__unwrap_iter(move_iterator<_Tp*> __i)
16963e519524SHoward Hinnant{
16973e519524SHoward Hinnant    return __i.base();
16983e519524SHoward Hinnant}
16993e519524SHoward Hinnant
1700fc88dbd2SHoward Hinnant#if _LIBCPP_DEBUG_LEVEL < 2
1701fc88dbd2SHoward Hinnant
17023e519524SHoward Hinnanttemplate <class _Tp>
17035b7c98e5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY
17043e519524SHoward Hinnanttypename enable_if
17053e519524SHoward Hinnant<
1706ca740483SHoward Hinnant    is_trivially_copy_assignable<_Tp>::value,
17073e519524SHoward Hinnant    _Tp*
17083e519524SHoward Hinnant>::type
17093e519524SHoward Hinnant__unwrap_iter(__wrap_iter<_Tp*> __i)
17103e519524SHoward Hinnant{
17113e519524SHoward Hinnant    return __i.base();
17123e519524SHoward Hinnant}
17133e519524SHoward Hinnant
171414bd0bf0SEric Fiselier#else
171514bd0bf0SEric Fiselier
171614bd0bf0SEric Fiseliertemplate <class _Tp>
17175b7c98e5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY
171814bd0bf0SEric Fiseliertypename enable_if
171914bd0bf0SEric Fiselier<
172014bd0bf0SEric Fiselier    is_trivially_copy_assignable<_Tp>::value,
172114bd0bf0SEric Fiselier    __wrap_iter<_Tp*>
172214bd0bf0SEric Fiselier>::type
172314bd0bf0SEric Fiselier__unwrap_iter(__wrap_iter<_Tp*> __i)
172414bd0bf0SEric Fiselier{
172514bd0bf0SEric Fiselier    return __i;
172614bd0bf0SEric Fiselier}
172714bd0bf0SEric Fiselier
1728fc88dbd2SHoward Hinnant#endif  // _LIBCPP_DEBUG_LEVEL < 2
1729fc88dbd2SHoward Hinnant
17303e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
17313e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17323e519524SHoward Hinnant_OutputIterator
17333e519524SHoward Hinnant__copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
17343e519524SHoward Hinnant{
1735910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
17363e519524SHoward Hinnant        *__result = *__first;
17373e519524SHoward Hinnant    return __result;
17383e519524SHoward Hinnant}
17393e519524SHoward Hinnant
17403e519524SHoward Hinnanttemplate <class _Tp, class _Up>
17413e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17423e519524SHoward Hinnanttypename enable_if
17433e519524SHoward Hinnant<
17443e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1745ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
17463e519524SHoward Hinnant    _Up*
17473e519524SHoward Hinnant>::type
17483e519524SHoward Hinnant__copy(_Tp* __first, _Tp* __last, _Up* __result)
17493e519524SHoward Hinnant{
17503e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
17515b312052SMarshall Clow    if (__n > 0)
1752ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
17533e519524SHoward Hinnant    return __result + __n;
17543e519524SHoward Hinnant}
17553e519524SHoward Hinnant
17563e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
17573e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17583e519524SHoward Hinnant_OutputIterator
17593e519524SHoward Hinnantcopy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
17603e519524SHoward Hinnant{
1761ce48a113SHoward Hinnant    return _VSTD::__copy(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
17623e519524SHoward Hinnant}
17633e519524SHoward Hinnant
17643e519524SHoward Hinnant// copy_backward
17653e519524SHoward Hinnant
1766d3d4356fSHoward Hinnanttemplate <class _BidirectionalIterator, class _OutputIterator>
17673e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17683e519524SHoward Hinnant_OutputIterator
1769d3d4356fSHoward Hinnant__copy_backward(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
17703e519524SHoward Hinnant{
17713e519524SHoward Hinnant    while (__first != __last)
17723e519524SHoward Hinnant        *--__result = *--__last;
17733e519524SHoward Hinnant    return __result;
17743e519524SHoward Hinnant}
17753e519524SHoward Hinnant
17763e519524SHoward Hinnanttemplate <class _Tp, class _Up>
17773e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17783e519524SHoward Hinnanttypename enable_if
17793e519524SHoward Hinnant<
17803e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1781ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
17823e519524SHoward Hinnant    _Up*
17833e519524SHoward Hinnant>::type
17843e519524SHoward Hinnant__copy_backward(_Tp* __first, _Tp* __last, _Up* __result)
17853e519524SHoward Hinnant{
17863e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
17875b312052SMarshall Clow    if (__n > 0)
17885b312052SMarshall Clow    {
17893e519524SHoward Hinnant        __result -= __n;
1790ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
17915b312052SMarshall Clow    }
17923e519524SHoward Hinnant    return __result;
17933e519524SHoward Hinnant}
17943e519524SHoward Hinnant
17953e519524SHoward Hinnanttemplate <class _BidirectionalIterator1, class _BidirectionalIterator2>
17963e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17973e519524SHoward Hinnant_BidirectionalIterator2
17983e519524SHoward Hinnantcopy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
17993e519524SHoward Hinnant              _BidirectionalIterator2 __result)
18003e519524SHoward Hinnant{
1801fd838227SEric Fiselier    return _VSTD::__copy_backward(__unwrap_iter(__first),
1802fd838227SEric Fiselier                                  __unwrap_iter(__last),
1803fd838227SEric Fiselier                                  __unwrap_iter(__result));
18043e519524SHoward Hinnant}
18053e519524SHoward Hinnant
18063e519524SHoward Hinnant// copy_if
18073e519524SHoward Hinnant
18083e519524SHoward Hinnanttemplate<class _InputIterator, class _OutputIterator, class _Predicate>
18093e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18103e519524SHoward Hinnant_OutputIterator
18113e519524SHoward Hinnantcopy_if(_InputIterator __first, _InputIterator __last,
18123e519524SHoward Hinnant        _OutputIterator __result, _Predicate __pred)
18133e519524SHoward Hinnant{
18143e519524SHoward Hinnant    for (; __first != __last; ++__first)
18153e519524SHoward Hinnant    {
18163e519524SHoward Hinnant        if (__pred(*__first))
18173e519524SHoward Hinnant        {
18183e519524SHoward Hinnant            *__result = *__first;
18193e519524SHoward Hinnant            ++__result;
18203e519524SHoward Hinnant        }
18213e519524SHoward Hinnant    }
18223e519524SHoward Hinnant    return __result;
18233e519524SHoward Hinnant}
18243e519524SHoward Hinnant
18253e519524SHoward Hinnant// copy_n
18263e519524SHoward Hinnant
18273e519524SHoward Hinnanttemplate<class _InputIterator, class _Size, class _OutputIterator>
18283e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18293e519524SHoward Hinnanttypename enable_if
18303e519524SHoward Hinnant<
18313e519524SHoward Hinnant    __is_input_iterator<_InputIterator>::value &&
18323e519524SHoward Hinnant   !__is_random_access_iterator<_InputIterator>::value,
18333e519524SHoward Hinnant    _OutputIterator
18343e519524SHoward Hinnant>::type
183551544023SEric Fiseliercopy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
18363e519524SHoward Hinnant{
183751544023SEric Fiselier    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
183851544023SEric Fiselier    _IntegralSize __n = __orig_n;
183999847d2bSHoward Hinnant    if (__n > 0)
184099847d2bSHoward Hinnant    {
18413e519524SHoward Hinnant        *__result = *__first;
184299847d2bSHoward Hinnant        ++__result;
184399847d2bSHoward Hinnant        for (--__n; __n > 0; --__n)
184499847d2bSHoward Hinnant        {
184599847d2bSHoward Hinnant            ++__first;
184699847d2bSHoward Hinnant            *__result = *__first;
184799847d2bSHoward Hinnant            ++__result;
184899847d2bSHoward Hinnant        }
184999847d2bSHoward Hinnant    }
18503e519524SHoward Hinnant    return __result;
18513e519524SHoward Hinnant}
18523e519524SHoward Hinnant
18533e519524SHoward Hinnanttemplate<class _InputIterator, class _Size, class _OutputIterator>
18543e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18553e519524SHoward Hinnanttypename enable_if
18563e519524SHoward Hinnant<
18573e519524SHoward Hinnant    __is_random_access_iterator<_InputIterator>::value,
18583e519524SHoward Hinnant    _OutputIterator
18593e519524SHoward Hinnant>::type
186051544023SEric Fiseliercopy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
18613e519524SHoward Hinnant{
186251544023SEric Fiselier    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
186351544023SEric Fiselier    _IntegralSize __n = __orig_n;
1864ce48a113SHoward Hinnant    return _VSTD::copy(__first, __first + __n, __result);
18653e519524SHoward Hinnant}
18663e519524SHoward Hinnant
18673e519524SHoward Hinnant// move
18683e519524SHoward Hinnant
18693e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
18703e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18713e519524SHoward Hinnant_OutputIterator
18723e519524SHoward Hinnant__move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18733e519524SHoward Hinnant{
1874910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
1875ce48a113SHoward Hinnant        *__result = _VSTD::move(*__first);
18763e519524SHoward Hinnant    return __result;
18773e519524SHoward Hinnant}
18783e519524SHoward Hinnant
18793e519524SHoward Hinnanttemplate <class _Tp, class _Up>
18803e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18813e519524SHoward Hinnanttypename enable_if
18823e519524SHoward Hinnant<
18833e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1884ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
18853e519524SHoward Hinnant    _Up*
18863e519524SHoward Hinnant>::type
18873e519524SHoward Hinnant__move(_Tp* __first, _Tp* __last, _Up* __result)
18883e519524SHoward Hinnant{
18893e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
18905b312052SMarshall Clow    if (__n > 0)
1891ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
18923e519524SHoward Hinnant    return __result + __n;
18933e519524SHoward Hinnant}
18943e519524SHoward Hinnant
18953e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
18963e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18973e519524SHoward Hinnant_OutputIterator
18983e519524SHoward Hinnantmove(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18993e519524SHoward Hinnant{
1900ce48a113SHoward Hinnant    return _VSTD::__move(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
19013e519524SHoward Hinnant}
19023e519524SHoward Hinnant
19033e519524SHoward Hinnant// move_backward
19043e519524SHoward Hinnant
19053e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
19063e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
19073e519524SHoward Hinnant_OutputIterator
19083e519524SHoward Hinnant__move_backward(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
19093e519524SHoward Hinnant{
19103e519524SHoward Hinnant    while (__first != __last)
1911ce48a113SHoward Hinnant        *--__result = _VSTD::move(*--__last);
19123e519524SHoward Hinnant    return __result;
19133e519524SHoward Hinnant}
19143e519524SHoward Hinnant
19153e519524SHoward Hinnanttemplate <class _Tp, class _Up>
19163e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
19173e519524SHoward Hinnanttypename enable_if
19183e519524SHoward Hinnant<
19193e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1920ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
19213e519524SHoward Hinnant    _Up*
19223e519524SHoward Hinnant>::type
19233e519524SHoward Hinnant__move_backward(_Tp* __first, _Tp* __last, _Up* __result)
19243e519524SHoward Hinnant{
19253e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
19265b312052SMarshall Clow    if (__n > 0)
19275b312052SMarshall Clow    {
19283e519524SHoward Hinnant        __result -= __n;
1929ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
19305b312052SMarshall Clow    }
19313e519524SHoward Hinnant    return __result;
19323e519524SHoward Hinnant}
19333e519524SHoward Hinnant
19343e519524SHoward Hinnanttemplate <class _BidirectionalIterator1, class _BidirectionalIterator2>
19353e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
19363e519524SHoward Hinnant_BidirectionalIterator2
19373e519524SHoward Hinnantmove_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
19383e519524SHoward Hinnant              _BidirectionalIterator2 __result)
19393e519524SHoward Hinnant{
1940ce48a113SHoward Hinnant    return _VSTD::__move_backward(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
19413e519524SHoward Hinnant}
19423e519524SHoward Hinnant
19433e519524SHoward Hinnant// iter_swap
19443e519524SHoward Hinnant
1945a676f7d3SHoward Hinnant// moved to <type_traits> for better swap / noexcept support
19463e519524SHoward Hinnant
19473e519524SHoward Hinnant// transform
19483e519524SHoward Hinnant
19493e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _UnaryOperation>
195099894b61SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19513e519524SHoward Hinnant_OutputIterator
19523e519524SHoward Hinnanttransform(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _UnaryOperation __op)
19533e519524SHoward Hinnant{
1954910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
19553e519524SHoward Hinnant        *__result = __op(*__first);
19563e519524SHoward Hinnant    return __result;
19573e519524SHoward Hinnant}
19583e519524SHoward Hinnant
19593e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _BinaryOperation>
196099894b61SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19613e519524SHoward Hinnant_OutputIterator
19623e519524SHoward Hinnanttransform(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
19633e519524SHoward Hinnant          _OutputIterator __result, _BinaryOperation __binary_op)
19643e519524SHoward Hinnant{
1965910285b2SEric Fiselier    for (; __first1 != __last1; ++__first1, (void) ++__first2, ++__result)
19663e519524SHoward Hinnant        *__result = __binary_op(*__first1, *__first2);
19673e519524SHoward Hinnant    return __result;
19683e519524SHoward Hinnant}
19693e519524SHoward Hinnant
19703e519524SHoward Hinnant// replace
19713e519524SHoward Hinnant
19723e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
197312c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19743e519524SHoward Hinnantvoid
19753e519524SHoward Hinnantreplace(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __old_value, const _Tp& __new_value)
19763e519524SHoward Hinnant{
19773e519524SHoward Hinnant    for (; __first != __last; ++__first)
19783e519524SHoward Hinnant        if (*__first == __old_value)
19793e519524SHoward Hinnant            *__first = __new_value;
19803e519524SHoward Hinnant}
19813e519524SHoward Hinnant
19823e519524SHoward Hinnant// replace_if
19833e519524SHoward Hinnant
19843e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate, class _Tp>
198512c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19863e519524SHoward Hinnantvoid
19873e519524SHoward Hinnantreplace_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, const _Tp& __new_value)
19883e519524SHoward Hinnant{
19893e519524SHoward Hinnant    for (; __first != __last; ++__first)
19903e519524SHoward Hinnant        if (__pred(*__first))
19913e519524SHoward Hinnant            *__first = __new_value;
19923e519524SHoward Hinnant}
19933e519524SHoward Hinnant
19943e519524SHoward Hinnant// replace_copy
19953e519524SHoward Hinnant
19963e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Tp>
199712c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19983e519524SHoward Hinnant_OutputIterator
19993e519524SHoward Hinnantreplace_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
20003e519524SHoward Hinnant             const _Tp& __old_value, const _Tp& __new_value)
20013e519524SHoward Hinnant{
2002910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
20033e519524SHoward Hinnant        if (*__first == __old_value)
20043e519524SHoward Hinnant            *__result = __new_value;
20053e519524SHoward Hinnant        else
20063e519524SHoward Hinnant            *__result = *__first;
20073e519524SHoward Hinnant    return __result;
20083e519524SHoward Hinnant}
20093e519524SHoward Hinnant
20103e519524SHoward Hinnant// replace_copy_if
20113e519524SHoward Hinnant
20123e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Predicate, class _Tp>
201312c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20143e519524SHoward Hinnant_OutputIterator
20153e519524SHoward Hinnantreplace_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
20163e519524SHoward Hinnant                _Predicate __pred, const _Tp& __new_value)
20173e519524SHoward Hinnant{
2018910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
20193e519524SHoward Hinnant        if (__pred(*__first))
20203e519524SHoward Hinnant            *__result = __new_value;
20213e519524SHoward Hinnant        else
20223e519524SHoward Hinnant            *__result = *__first;
20233e519524SHoward Hinnant    return __result;
20243e519524SHoward Hinnant}
20253e519524SHoward Hinnant
20263e519524SHoward Hinnant// fill_n
20273e519524SHoward Hinnant
20283e519524SHoward Hinnanttemplate <class _OutputIterator, class _Size, class _Tp>
20294bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20303e519524SHoward Hinnant_OutputIterator
20310f242beaSHoward Hinnant__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
20323e519524SHoward Hinnant{
2033910285b2SEric Fiselier    for (; __n > 0; ++__first, (void) --__n)
2034e4383379SHoward Hinnant        *__first = __value_;
20353e519524SHoward Hinnant    return __first;
20363e519524SHoward Hinnant}
20373e519524SHoward Hinnant
20383e519524SHoward Hinnanttemplate <class _OutputIterator, class _Size, class _Tp>
20394bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20403e519524SHoward Hinnant_OutputIterator
2041e4383379SHoward Hinnantfill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
20423e519524SHoward Hinnant{
204351544023SEric Fiselier   return _VSTD::__fill_n(__first, __convert_to_integral(__n), __value_);
20443e519524SHoward Hinnant}
20453e519524SHoward Hinnant
20463e519524SHoward Hinnant// fill
20473e519524SHoward Hinnant
20483e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
20494bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20503e519524SHoward Hinnantvoid
2051e4383379SHoward Hinnant__fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, forward_iterator_tag)
20523e519524SHoward Hinnant{
20533e519524SHoward Hinnant    for (; __first != __last; ++__first)
2054e4383379SHoward Hinnant        *__first = __value_;
20553e519524SHoward Hinnant}
20563e519524SHoward Hinnant
20573e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Tp>
20584bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20593e519524SHoward Hinnantvoid
2060e4383379SHoward Hinnant__fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value_, random_access_iterator_tag)
20613e519524SHoward Hinnant{
2062e4383379SHoward Hinnant    _VSTD::fill_n(__first, __last - __first, __value_);
20633e519524SHoward Hinnant}
20643e519524SHoward Hinnant
20653e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
20664bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20673e519524SHoward Hinnantvoid
2068e4383379SHoward Hinnantfill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
20693e519524SHoward Hinnant{
2070e4383379SHoward Hinnant    _VSTD::__fill(__first, __last, __value_, typename iterator_traits<_ForwardIterator>::iterator_category());
20713e519524SHoward Hinnant}
20723e519524SHoward Hinnant
20733e519524SHoward Hinnant// generate
20743e519524SHoward Hinnant
20753e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Generator>
20764bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20773e519524SHoward Hinnantvoid
20783e519524SHoward Hinnantgenerate(_ForwardIterator __first, _ForwardIterator __last, _Generator __gen)
20793e519524SHoward Hinnant{
20803e519524SHoward Hinnant    for (; __first != __last; ++__first)
20813e519524SHoward Hinnant        *__first = __gen();
20823e519524SHoward Hinnant}
20833e519524SHoward Hinnant
20843e519524SHoward Hinnant// generate_n
20853e519524SHoward Hinnant
20863e519524SHoward Hinnanttemplate <class _OutputIterator, class _Size, class _Generator>
20874bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY  _LIBCPP_CONSTEXPR_AFTER_CXX17
20883e519524SHoward Hinnant_OutputIterator
208951544023SEric Fiseliergenerate_n(_OutputIterator __first, _Size __orig_n, _Generator __gen)
20903e519524SHoward Hinnant{
209151544023SEric Fiselier    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
209251544023SEric Fiselier    _IntegralSize __n = __orig_n;
2093910285b2SEric Fiselier    for (; __n > 0; ++__first, (void) --__n)
20943e519524SHoward Hinnant        *__first = __gen();
20953e519524SHoward Hinnant    return __first;
20963e519524SHoward Hinnant}
20973e519524SHoward Hinnant
20983e519524SHoward Hinnant// remove
20993e519524SHoward Hinnant
21003e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
2101*e8ea8296SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2102e4383379SHoward Hinnantremove(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
21033e519524SHoward Hinnant{
2104e4383379SHoward Hinnant    __first = _VSTD::find(__first, __last, __value_);
21053e519524SHoward Hinnant    if (__first != __last)
21063e519524SHoward Hinnant    {
21073e519524SHoward Hinnant        _ForwardIterator __i = __first;
21083e519524SHoward Hinnant        while (++__i != __last)
21093e519524SHoward Hinnant        {
2110e4383379SHoward Hinnant            if (!(*__i == __value_))
21113e519524SHoward Hinnant            {
2112ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
21133e519524SHoward Hinnant                ++__first;
21143e519524SHoward Hinnant            }
21153e519524SHoward Hinnant        }
21163e519524SHoward Hinnant    }
21173e519524SHoward Hinnant    return __first;
21183e519524SHoward Hinnant}
21193e519524SHoward Hinnant
21203e519524SHoward Hinnant// remove_if
21213e519524SHoward Hinnant
21223e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate>
2123*e8ea8296SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
21243e519524SHoward Hinnantremove_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
21253e519524SHoward Hinnant{
2126ce48a113SHoward Hinnant    __first = _VSTD::find_if<_ForwardIterator, typename add_lvalue_reference<_Predicate>::type>
21273e519524SHoward Hinnant                           (__first, __last, __pred);
21283e519524SHoward Hinnant    if (__first != __last)
21293e519524SHoward Hinnant    {
21303e519524SHoward Hinnant        _ForwardIterator __i = __first;
21313e519524SHoward Hinnant        while (++__i != __last)
21323e519524SHoward Hinnant        {
21333e519524SHoward Hinnant            if (!__pred(*__i))
21343e519524SHoward Hinnant            {
2135ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
21363e519524SHoward Hinnant                ++__first;
21373e519524SHoward Hinnant            }
21383e519524SHoward Hinnant        }
21393e519524SHoward Hinnant    }
21403e519524SHoward Hinnant    return __first;
21413e519524SHoward Hinnant}
21423e519524SHoward Hinnant
21433e519524SHoward Hinnant// remove_copy
21443e519524SHoward Hinnant
21453e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Tp>
2146*e8ea8296SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21473e519524SHoward Hinnant_OutputIterator
2148e4383379SHoward Hinnantremove_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, const _Tp& __value_)
21493e519524SHoward Hinnant{
21503e519524SHoward Hinnant    for (; __first != __last; ++__first)
21513e519524SHoward Hinnant    {
2152e4383379SHoward Hinnant        if (!(*__first == __value_))
21533e519524SHoward Hinnant        {
21543e519524SHoward Hinnant            *__result = *__first;
21553e519524SHoward Hinnant            ++__result;
21563e519524SHoward Hinnant        }
21573e519524SHoward Hinnant    }
21583e519524SHoward Hinnant    return __result;
21593e519524SHoward Hinnant}
21603e519524SHoward Hinnant
21613e519524SHoward Hinnant// remove_copy_if
21623e519524SHoward Hinnant
21633e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Predicate>
2164*e8ea8296SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21653e519524SHoward Hinnant_OutputIterator
21663e519524SHoward Hinnantremove_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred)
21673e519524SHoward Hinnant{
21683e519524SHoward Hinnant    for (; __first != __last; ++__first)
21693e519524SHoward Hinnant    {
21703e519524SHoward Hinnant        if (!__pred(*__first))
21713e519524SHoward Hinnant        {
21723e519524SHoward Hinnant            *__result = *__first;
21733e519524SHoward Hinnant            ++__result;
21743e519524SHoward Hinnant        }
21753e519524SHoward Hinnant    }
21763e519524SHoward Hinnant    return __result;
21773e519524SHoward Hinnant}
21783e519524SHoward Hinnant
21793e519524SHoward Hinnant// unique
21803e519524SHoward Hinnant
21813e519524SHoward Hinnanttemplate <class _ForwardIterator, class _BinaryPredicate>
21824bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
21833e519524SHoward Hinnantunique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
21843e519524SHoward Hinnant{
2185ce48a113SHoward Hinnant    __first = _VSTD::adjacent_find<_ForwardIterator, typename add_lvalue_reference<_BinaryPredicate>::type>
21863e519524SHoward Hinnant                                 (__first, __last, __pred);
21873e519524SHoward Hinnant    if (__first != __last)
21883e519524SHoward Hinnant    {
21893e519524SHoward Hinnant        // ...  a  a  ?  ...
21903e519524SHoward Hinnant        //      f     i
21913e519524SHoward Hinnant        _ForwardIterator __i = __first;
21923e519524SHoward Hinnant        for (++__i; ++__i != __last;)
21933e519524SHoward Hinnant            if (!__pred(*__first, *__i))
2194ce48a113SHoward Hinnant                *++__first = _VSTD::move(*__i);
21953e519524SHoward Hinnant        ++__first;
21963e519524SHoward Hinnant    }
21973e519524SHoward Hinnant    return __first;
21983e519524SHoward Hinnant}
21993e519524SHoward Hinnant
22003e519524SHoward Hinnanttemplate <class _ForwardIterator>
22014bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22023e519524SHoward Hinnant_ForwardIterator
22033e519524SHoward Hinnantunique(_ForwardIterator __first, _ForwardIterator __last)
22043e519524SHoward Hinnant{
22053e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
2206ce48a113SHoward Hinnant    return _VSTD::unique(__first, __last, __equal_to<__v>());
22073e519524SHoward Hinnant}
22083e519524SHoward Hinnant
22093e519524SHoward Hinnant// unique_copy
22103e519524SHoward Hinnant
22113e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _InputIterator, class _OutputIterator>
22124bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
22133e519524SHoward Hinnant__unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
22143e519524SHoward Hinnant              input_iterator_tag, output_iterator_tag)
22153e519524SHoward Hinnant{
22163e519524SHoward Hinnant    if (__first != __last)
22173e519524SHoward Hinnant    {
22183e519524SHoward Hinnant        typename iterator_traits<_InputIterator>::value_type __t(*__first);
22193e519524SHoward Hinnant        *__result = __t;
22203e519524SHoward Hinnant        ++__result;
22213e519524SHoward Hinnant        while (++__first != __last)
22223e519524SHoward Hinnant        {
22233e519524SHoward Hinnant            if (!__pred(__t, *__first))
22243e519524SHoward Hinnant            {
22253e519524SHoward Hinnant                __t = *__first;
22263e519524SHoward Hinnant                *__result = __t;
22273e519524SHoward Hinnant                ++__result;
22283e519524SHoward Hinnant            }
22293e519524SHoward Hinnant        }
22303e519524SHoward Hinnant    }
22313e519524SHoward Hinnant    return __result;
22323e519524SHoward Hinnant}
22333e519524SHoward Hinnant
22343e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _ForwardIterator, class _OutputIterator>
22354bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
22363e519524SHoward Hinnant__unique_copy(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
22373e519524SHoward Hinnant              forward_iterator_tag, output_iterator_tag)
22383e519524SHoward Hinnant{
22393e519524SHoward Hinnant    if (__first != __last)
22403e519524SHoward Hinnant    {
22413e519524SHoward Hinnant        _ForwardIterator __i = __first;
22423e519524SHoward Hinnant        *__result = *__i;
22433e519524SHoward Hinnant        ++__result;
22443e519524SHoward Hinnant        while (++__first != __last)
22453e519524SHoward Hinnant        {
22463e519524SHoward Hinnant            if (!__pred(*__i, *__first))
22473e519524SHoward Hinnant            {
22483e519524SHoward Hinnant                *__result = *__first;
22493e519524SHoward Hinnant                ++__result;
22503e519524SHoward Hinnant                __i = __first;
22513e519524SHoward Hinnant            }
22523e519524SHoward Hinnant        }
22533e519524SHoward Hinnant    }
22543e519524SHoward Hinnant    return __result;
22553e519524SHoward Hinnant}
22563e519524SHoward Hinnant
22573e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _InputIterator, class _ForwardIterator>
22584bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
22593e519524SHoward Hinnant__unique_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result, _BinaryPredicate __pred,
22603e519524SHoward Hinnant              input_iterator_tag, forward_iterator_tag)
22613e519524SHoward Hinnant{
22623e519524SHoward Hinnant    if (__first != __last)
22633e519524SHoward Hinnant    {
22643e519524SHoward Hinnant        *__result = *__first;
22653e519524SHoward Hinnant        while (++__first != __last)
22663e519524SHoward Hinnant            if (!__pred(*__result, *__first))
22673e519524SHoward Hinnant                *++__result = *__first;
22683e519524SHoward Hinnant        ++__result;
22693e519524SHoward Hinnant    }
22703e519524SHoward Hinnant    return __result;
22713e519524SHoward Hinnant}
22723e519524SHoward Hinnant
22733e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
22744bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22753e519524SHoward Hinnant_OutputIterator
22763e519524SHoward Hinnantunique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred)
22773e519524SHoward Hinnant{
2278ce48a113SHoward Hinnant    return _VSTD::__unique_copy<typename add_lvalue_reference<_BinaryPredicate>::type>
22793e519524SHoward Hinnant                              (__first, __last, __result, __pred,
22803e519524SHoward Hinnant                               typename iterator_traits<_InputIterator>::iterator_category(),
22813e519524SHoward Hinnant                               typename iterator_traits<_OutputIterator>::iterator_category());
22823e519524SHoward Hinnant}
22833e519524SHoward Hinnant
22843e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
22854bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22863e519524SHoward Hinnant_OutputIterator
22873e519524SHoward Hinnantunique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
22883e519524SHoward Hinnant{
22893e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator>::value_type __v;
2290ce48a113SHoward Hinnant    return _VSTD::unique_copy(__first, __last, __result, __equal_to<__v>());
22913e519524SHoward Hinnant}
22923e519524SHoward Hinnant
22933e519524SHoward Hinnant// reverse
22943e519524SHoward Hinnant
22953e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
22963e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
22973e519524SHoward Hinnantvoid
22983e519524SHoward Hinnant__reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag)
22993e519524SHoward Hinnant{
23003e519524SHoward Hinnant    while (__first != __last)
23013e519524SHoward Hinnant    {
23023e519524SHoward Hinnant        if (__first == --__last)
23033e519524SHoward Hinnant            break;
2304def501d1SMarshall Clow        _VSTD::iter_swap(__first, __last);
23053e519524SHoward Hinnant        ++__first;
23063e519524SHoward Hinnant    }
23073e519524SHoward Hinnant}
23083e519524SHoward Hinnant
23093e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
23103e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
23113e519524SHoward Hinnantvoid
23123e519524SHoward Hinnant__reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag)
23133e519524SHoward Hinnant{
23143e519524SHoward Hinnant    if (__first != __last)
23153e519524SHoward Hinnant        for (; __first < --__last; ++__first)
2316def501d1SMarshall Clow            _VSTD::iter_swap(__first, __last);
23173e519524SHoward Hinnant}
23183e519524SHoward Hinnant
23193e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
23203e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
23213e519524SHoward Hinnantvoid
23223e519524SHoward Hinnantreverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
23233e519524SHoward Hinnant{
2324ce48a113SHoward Hinnant    _VSTD::__reverse(__first, __last, typename iterator_traits<_BidirectionalIterator>::iterator_category());
23253e519524SHoward Hinnant}
23263e519524SHoward Hinnant
23273e519524SHoward Hinnant// reverse_copy
23283e519524SHoward Hinnant
23293e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _OutputIterator>
2330*e8ea8296SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
23313e519524SHoward Hinnant_OutputIterator
23323e519524SHoward Hinnantreverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
23333e519524SHoward Hinnant{
23343e519524SHoward Hinnant    for (; __first != __last; ++__result)
23353e519524SHoward Hinnant        *__result = *--__last;
23363e519524SHoward Hinnant    return __result;
23373e519524SHoward Hinnant}
23383e519524SHoward Hinnant
23393e519524SHoward Hinnant// rotate
23403e519524SHoward Hinnant
23413e519524SHoward Hinnanttemplate <class _ForwardIterator>
23423e519524SHoward Hinnant_ForwardIterator
2343aca09de3SHoward Hinnant__rotate_left(_ForwardIterator __first, _ForwardIterator __last)
23443e519524SHoward Hinnant{
2345aca09de3SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
2346aca09de3SHoward Hinnant    value_type __tmp = _VSTD::move(*__first);
2347aca09de3SHoward Hinnant    _ForwardIterator __lm1 = _VSTD::move(_VSTD::next(__first), __last, __first);
2348aca09de3SHoward Hinnant    *__lm1 = _VSTD::move(__tmp);
2349aca09de3SHoward Hinnant    return __lm1;
2350aca09de3SHoward Hinnant}
2351aca09de3SHoward Hinnant
2352aca09de3SHoward Hinnanttemplate <class _BidirectionalIterator>
2353aca09de3SHoward Hinnant_BidirectionalIterator
2354aca09de3SHoward Hinnant__rotate_right(_BidirectionalIterator __first, _BidirectionalIterator __last)
2355aca09de3SHoward Hinnant{
2356aca09de3SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
2357aca09de3SHoward Hinnant    _BidirectionalIterator __lm1 = _VSTD::prev(__last);
2358aca09de3SHoward Hinnant    value_type __tmp = _VSTD::move(*__lm1);
2359aca09de3SHoward Hinnant    _BidirectionalIterator __fp1 = _VSTD::move_backward(__first, __lm1, __last);
2360aca09de3SHoward Hinnant    *__first = _VSTD::move(__tmp);
2361aca09de3SHoward Hinnant    return __fp1;
2362aca09de3SHoward Hinnant}
2363aca09de3SHoward Hinnant
2364aca09de3SHoward Hinnanttemplate <class _ForwardIterator>
2365aca09de3SHoward Hinnant_ForwardIterator
2366aca09de3SHoward Hinnant__rotate_forward(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
2367aca09de3SHoward Hinnant{
23683e519524SHoward Hinnant    _ForwardIterator __i = __middle;
23693e519524SHoward Hinnant    while (true)
23703e519524SHoward Hinnant    {
23713e519524SHoward Hinnant        swap(*__first, *__i);
23723e519524SHoward Hinnant        ++__first;
23733e519524SHoward Hinnant        if (++__i == __last)
23743e519524SHoward Hinnant            break;
23753e519524SHoward Hinnant        if (__first == __middle)
23763e519524SHoward Hinnant            __middle = __i;
23773e519524SHoward Hinnant    }
23783e519524SHoward Hinnant    _ForwardIterator __r = __first;
23793e519524SHoward Hinnant    if (__first != __middle)
23803e519524SHoward Hinnant    {
23813e519524SHoward Hinnant        __i = __middle;
23823e519524SHoward Hinnant        while (true)
23833e519524SHoward Hinnant        {
23843e519524SHoward Hinnant            swap(*__first, *__i);
23853e519524SHoward Hinnant            ++__first;
23863e519524SHoward Hinnant            if (++__i == __last)
23873e519524SHoward Hinnant            {
23883e519524SHoward Hinnant                if (__first == __middle)
23893e519524SHoward Hinnant                    break;
23903e519524SHoward Hinnant                __i = __middle;
23913e519524SHoward Hinnant            }
23923e519524SHoward Hinnant            else if (__first == __middle)
23933e519524SHoward Hinnant                __middle = __i;
23943e519524SHoward Hinnant        }
23953e519524SHoward Hinnant    }
23963e519524SHoward Hinnant    return __r;
23973e519524SHoward Hinnant}
23983e519524SHoward Hinnant
23993e519524SHoward Hinnanttemplate<typename _Integral>
24003e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
24013e519524SHoward Hinnant_Integral
240219b4035fSMarshall Clow__algo_gcd(_Integral __x, _Integral __y)
24033e519524SHoward Hinnant{
24043e519524SHoward Hinnant    do
24053e519524SHoward Hinnant    {
24063e519524SHoward Hinnant        _Integral __t = __x % __y;
24073e519524SHoward Hinnant        __x = __y;
24083e519524SHoward Hinnant        __y = __t;
24093e519524SHoward Hinnant    } while (__y);
24103e519524SHoward Hinnant    return __x;
24113e519524SHoward Hinnant}
24123e519524SHoward Hinnant
24133e519524SHoward Hinnanttemplate<typename _RandomAccessIterator>
24143e519524SHoward Hinnant_RandomAccessIterator
2415aca09de3SHoward Hinnant__rotate_gcd(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
24163e519524SHoward Hinnant{
24173e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
24183e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
24193e519524SHoward Hinnant
24203e519524SHoward Hinnant    const difference_type __m1 = __middle - __first;
24213e519524SHoward Hinnant    const difference_type __m2 = __last - __middle;
24223e519524SHoward Hinnant    if (__m1 == __m2)
24233e519524SHoward Hinnant    {
2424ce48a113SHoward Hinnant        _VSTD::swap_ranges(__first, __middle, __middle);
24253e519524SHoward Hinnant        return __middle;
24263e519524SHoward Hinnant    }
242719b4035fSMarshall Clow    const difference_type __g = _VSTD::__algo_gcd(__m1, __m2);
24283e519524SHoward Hinnant    for (_RandomAccessIterator __p = __first + __g; __p != __first;)
24293e519524SHoward Hinnant    {
2430aca09de3SHoward Hinnant        value_type __t(_VSTD::move(*--__p));
24313e519524SHoward Hinnant        _RandomAccessIterator __p1 = __p;
24323e519524SHoward Hinnant        _RandomAccessIterator __p2 = __p1 + __m1;
24333e519524SHoward Hinnant        do
24343e519524SHoward Hinnant        {
2435aca09de3SHoward Hinnant            *__p1 = _VSTD::move(*__p2);
24363e519524SHoward Hinnant            __p1 = __p2;
24373e519524SHoward Hinnant            const difference_type __d = __last - __p2;
24383e519524SHoward Hinnant            if (__m1 < __d)
24393e519524SHoward Hinnant                __p2 += __m1;
24403e519524SHoward Hinnant            else
24413e519524SHoward Hinnant                __p2 = __first + (__m1 - __d);
24423e519524SHoward Hinnant        } while (__p2 != __p);
2443aca09de3SHoward Hinnant        *__p1 = _VSTD::move(__t);
24443e519524SHoward Hinnant    }
24453e519524SHoward Hinnant    return __first + __m2;
24463e519524SHoward Hinnant}
24473e519524SHoward Hinnant
24483e519524SHoward Hinnanttemplate <class _ForwardIterator>
24493e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
24503e519524SHoward Hinnant_ForwardIterator
2451aca09de3SHoward Hinnant__rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last,
2452aca09de3SHoward Hinnant         _VSTD::forward_iterator_tag)
2453aca09de3SHoward Hinnant{
2454aca09de3SHoward Hinnant    typedef typename _VSTD::iterator_traits<_ForwardIterator>::value_type value_type;
2455aca09de3SHoward Hinnant    if (_VSTD::is_trivially_move_assignable<value_type>::value)
2456aca09de3SHoward Hinnant    {
2457aca09de3SHoward Hinnant        if (_VSTD::next(__first) == __middle)
2458aca09de3SHoward Hinnant            return _VSTD::__rotate_left(__first, __last);
2459aca09de3SHoward Hinnant    }
2460aca09de3SHoward Hinnant    return _VSTD::__rotate_forward(__first, __middle, __last);
2461aca09de3SHoward Hinnant}
2462aca09de3SHoward Hinnant
2463aca09de3SHoward Hinnanttemplate <class _BidirectionalIterator>
2464aca09de3SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
2465aca09de3SHoward Hinnant_BidirectionalIterator
2466aca09de3SHoward Hinnant__rotate(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
2467aca09de3SHoward Hinnant         _VSTD::bidirectional_iterator_tag)
2468aca09de3SHoward Hinnant{
2469aca09de3SHoward Hinnant    typedef typename _VSTD::iterator_traits<_BidirectionalIterator>::value_type value_type;
2470aca09de3SHoward Hinnant    if (_VSTD::is_trivially_move_assignable<value_type>::value)
2471aca09de3SHoward Hinnant    {
2472aca09de3SHoward Hinnant        if (_VSTD::next(__first) == __middle)
2473aca09de3SHoward Hinnant            return _VSTD::__rotate_left(__first, __last);
2474aca09de3SHoward Hinnant        if (_VSTD::next(__middle) == __last)
2475aca09de3SHoward Hinnant            return _VSTD::__rotate_right(__first, __last);
2476aca09de3SHoward Hinnant    }
2477aca09de3SHoward Hinnant    return _VSTD::__rotate_forward(__first, __middle, __last);
2478aca09de3SHoward Hinnant}
2479aca09de3SHoward Hinnant
2480aca09de3SHoward Hinnanttemplate <class _RandomAccessIterator>
2481aca09de3SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
2482aca09de3SHoward Hinnant_RandomAccessIterator
2483aca09de3SHoward Hinnant__rotate(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
2484aca09de3SHoward Hinnant         _VSTD::random_access_iterator_tag)
2485aca09de3SHoward Hinnant{
2486aca09de3SHoward Hinnant    typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::value_type value_type;
2487aca09de3SHoward Hinnant    if (_VSTD::is_trivially_move_assignable<value_type>::value)
2488aca09de3SHoward Hinnant    {
2489aca09de3SHoward Hinnant        if (_VSTD::next(__first) == __middle)
2490aca09de3SHoward Hinnant            return _VSTD::__rotate_left(__first, __last);
2491aca09de3SHoward Hinnant        if (_VSTD::next(__middle) == __last)
2492aca09de3SHoward Hinnant            return _VSTD::__rotate_right(__first, __last);
2493aca09de3SHoward Hinnant        return _VSTD::__rotate_gcd(__first, __middle, __last);
2494aca09de3SHoward Hinnant    }
2495aca09de3SHoward Hinnant    return _VSTD::__rotate_forward(__first, __middle, __last);
2496aca09de3SHoward Hinnant}
2497aca09de3SHoward Hinnant
2498aca09de3SHoward Hinnanttemplate <class _ForwardIterator>
2499aca09de3SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
2500aca09de3SHoward Hinnant_ForwardIterator
25013e519524SHoward Hinnantrotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
25023e519524SHoward Hinnant{
2503aca09de3SHoward Hinnant    if (__first == __middle)
2504aca09de3SHoward Hinnant        return __last;
2505aca09de3SHoward Hinnant    if (__middle == __last)
2506aca09de3SHoward Hinnant        return __first;
2507ce48a113SHoward Hinnant    return _VSTD::__rotate(__first, __middle, __last,
2508aca09de3SHoward Hinnant                           typename _VSTD::iterator_traits<_ForwardIterator>::iterator_category());
25093e519524SHoward Hinnant}
25103e519524SHoward Hinnant
25113e519524SHoward Hinnant// rotate_copy
25123e519524SHoward Hinnant
25133e519524SHoward Hinnanttemplate <class _ForwardIterator, class _OutputIterator>
25143e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
25153e519524SHoward Hinnant_OutputIterator
25163e519524SHoward Hinnantrotate_copy(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, _OutputIterator __result)
25173e519524SHoward Hinnant{
2518ce48a113SHoward Hinnant    return _VSTD::copy(__first, __middle, _VSTD::copy(__middle, __last, __result));
25193e519524SHoward Hinnant}
25203e519524SHoward Hinnant
25213e519524SHoward Hinnant// min_element
25223e519524SHoward Hinnant
25233e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
25249d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25253e519524SHoward Hinnant_ForwardIterator
25260b0671aeSMarshall Clowmin_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
25273e519524SHoward Hinnant{
25283e519524SHoward Hinnant    if (__first != __last)
25293e519524SHoward Hinnant    {
25303e519524SHoward Hinnant        _ForwardIterator __i = __first;
25313e519524SHoward Hinnant        while (++__i != __last)
25323e519524SHoward Hinnant            if (__comp(*__i, *__first))
25333e519524SHoward Hinnant                __first = __i;
25343e519524SHoward Hinnant    }
25353e519524SHoward Hinnant    return __first;
25363e519524SHoward Hinnant}
25373e519524SHoward Hinnant
25383e519524SHoward Hinnanttemplate <class _ForwardIterator>
25390b0671aeSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25403e519524SHoward Hinnant_ForwardIterator
25413e519524SHoward Hinnantmin_element(_ForwardIterator __first, _ForwardIterator __last)
25423e519524SHoward Hinnant{
25430b0671aeSMarshall Clow    return _VSTD::min_element(__first, __last,
25444eb27b79SHoward Hinnant              __less<typename iterator_traits<_ForwardIterator>::value_type>());
25454eb27b79SHoward Hinnant}
25464eb27b79SHoward Hinnant
25474eb27b79SHoward Hinnant// min
25484eb27b79SHoward Hinnant
25494eb27b79SHoward Hinnanttemplate <class _Tp, class _Compare>
25509d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25514eb27b79SHoward Hinnantconst _Tp&
25524eb27b79SHoward Hinnantmin(const _Tp& __a, const _Tp& __b, _Compare __comp)
25534eb27b79SHoward Hinnant{
25544eb27b79SHoward Hinnant    return __comp(__b, __a) ? __b : __a;
25554eb27b79SHoward Hinnant}
25564eb27b79SHoward Hinnant
25574eb27b79SHoward Hinnanttemplate <class _Tp>
25589d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25594eb27b79SHoward Hinnantconst _Tp&
25604eb27b79SHoward Hinnantmin(const _Tp& __a, const _Tp& __b)
25614eb27b79SHoward Hinnant{
2562ce48a113SHoward Hinnant    return _VSTD::min(__a, __b, __less<_Tp>());
25634eb27b79SHoward Hinnant}
25644eb27b79SHoward Hinnant
2565ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
256654976f26SHoward Hinnant
25674eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
25689d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25694eb27b79SHoward Hinnant_Tp
25704eb27b79SHoward Hinnantmin(initializer_list<_Tp> __t, _Compare __comp)
25714eb27b79SHoward Hinnant{
25720b0671aeSMarshall Clow    return *_VSTD::min_element(__t.begin(), __t.end(), __comp);
25734eb27b79SHoward Hinnant}
25744eb27b79SHoward Hinnant
25754eb27b79SHoward Hinnanttemplate<class _Tp>
25769d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25774eb27b79SHoward Hinnant_Tp
25784eb27b79SHoward Hinnantmin(initializer_list<_Tp> __t)
25794eb27b79SHoward Hinnant{
25800b0671aeSMarshall Clow    return *_VSTD::min_element(__t.begin(), __t.end(), __less<_Tp>());
25813e519524SHoward Hinnant}
25823e519524SHoward Hinnant
2583ddda456aSEric Fiselier#endif  // _LIBCPP_CXX03_LANG
258454976f26SHoward Hinnant
25853e519524SHoward Hinnant// max_element
25863e519524SHoward Hinnant
25873e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
25889d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25893e519524SHoward Hinnant_ForwardIterator
25900b0671aeSMarshall Clowmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
25913e519524SHoward Hinnant{
25923e519524SHoward Hinnant    if (__first != __last)
25933e519524SHoward Hinnant    {
25943e519524SHoward Hinnant        _ForwardIterator __i = __first;
25953e519524SHoward Hinnant        while (++__i != __last)
25963e519524SHoward Hinnant            if (__comp(*__first, *__i))
25973e519524SHoward Hinnant                __first = __i;
25983e519524SHoward Hinnant    }
25993e519524SHoward Hinnant    return __first;
26003e519524SHoward Hinnant}
26013e519524SHoward Hinnant
26029d67c6d5SMarshall Clow
26033e519524SHoward Hinnanttemplate <class _ForwardIterator>
26040b0671aeSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26053e519524SHoward Hinnant_ForwardIterator
26063e519524SHoward Hinnantmax_element(_ForwardIterator __first, _ForwardIterator __last)
26073e519524SHoward Hinnant{
26080b0671aeSMarshall Clow    return _VSTD::max_element(__first, __last,
26094eb27b79SHoward Hinnant              __less<typename iterator_traits<_ForwardIterator>::value_type>());
26104eb27b79SHoward Hinnant}
26114eb27b79SHoward Hinnant
26124eb27b79SHoward Hinnant// max
26134eb27b79SHoward Hinnant
26144eb27b79SHoward Hinnanttemplate <class _Tp, class _Compare>
26159d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26164eb27b79SHoward Hinnantconst _Tp&
26174eb27b79SHoward Hinnantmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
26184eb27b79SHoward Hinnant{
26194eb27b79SHoward Hinnant    return __comp(__a, __b) ? __b : __a;
26204eb27b79SHoward Hinnant}
26214eb27b79SHoward Hinnant
26224eb27b79SHoward Hinnanttemplate <class _Tp>
26239d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26244eb27b79SHoward Hinnantconst _Tp&
26254eb27b79SHoward Hinnantmax(const _Tp& __a, const _Tp& __b)
26264eb27b79SHoward Hinnant{
2627ce48a113SHoward Hinnant    return _VSTD::max(__a, __b, __less<_Tp>());
26284eb27b79SHoward Hinnant}
26294eb27b79SHoward Hinnant
2630ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
263154976f26SHoward Hinnant
26324eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
26339d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26344eb27b79SHoward Hinnant_Tp
26354eb27b79SHoward Hinnantmax(initializer_list<_Tp> __t, _Compare __comp)
26364eb27b79SHoward Hinnant{
26370b0671aeSMarshall Clow    return *_VSTD::max_element(__t.begin(), __t.end(), __comp);
26384eb27b79SHoward Hinnant}
26394eb27b79SHoward Hinnant
26404eb27b79SHoward Hinnanttemplate<class _Tp>
26419d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26424eb27b79SHoward Hinnant_Tp
26434eb27b79SHoward Hinnantmax(initializer_list<_Tp> __t)
26444eb27b79SHoward Hinnant{
26450b0671aeSMarshall Clow    return *_VSTD::max_element(__t.begin(), __t.end(), __less<_Tp>());
26463e519524SHoward Hinnant}
26473e519524SHoward Hinnant
2648ddda456aSEric Fiselier#endif  // _LIBCPP_CXX03_LANG
264954976f26SHoward Hinnant
2650146c14acSMarshall Clow#if _LIBCPP_STD_VER > 14
2651146c14acSMarshall Clow// clamp
2652146c14acSMarshall Clowtemplate<class _Tp, class _Compare>
2653146c14acSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2654146c14acSMarshall Clowconst _Tp&
2655146c14acSMarshall Clowclamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi, _Compare __comp)
2656146c14acSMarshall Clow{
2657146c14acSMarshall Clow    _LIBCPP_ASSERT(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
2658146c14acSMarshall Clow    return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
2659146c14acSMarshall Clow
2660146c14acSMarshall Clow}
2661146c14acSMarshall Clow
2662146c14acSMarshall Clowtemplate<class _Tp>
2663146c14acSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2664146c14acSMarshall Clowconst _Tp&
2665146c14acSMarshall Clowclamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi)
2666146c14acSMarshall Clow{
2667146c14acSMarshall Clow    return _VSTD::clamp(__v, __lo, __hi, __less<_Tp>());
2668146c14acSMarshall Clow}
2669146c14acSMarshall Clow#endif
2670146c14acSMarshall Clow
26713e519524SHoward Hinnant// minmax_element
26723e519524SHoward Hinnant
26733e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
26740b0671aeSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX11
26753e519524SHoward Hinnantstd::pair<_ForwardIterator, _ForwardIterator>
26763e519524SHoward Hinnantminmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
26773e519524SHoward Hinnant{
26783e519524SHoward Hinnant  std::pair<_ForwardIterator, _ForwardIterator> __result(__first, __first);
26793e519524SHoward Hinnant  if (__first != __last)
26803e519524SHoward Hinnant  {
26813e519524SHoward Hinnant      if (++__first != __last)
26823e519524SHoward Hinnant      {
26833e519524SHoward Hinnant          if (__comp(*__first, *__result.first))
26843e519524SHoward Hinnant              __result.first = __first;
26853e519524SHoward Hinnant          else
26863e519524SHoward Hinnant              __result.second = __first;
26873e519524SHoward Hinnant          while (++__first != __last)
26883e519524SHoward Hinnant          {
26893e519524SHoward Hinnant              _ForwardIterator __i = __first;
26903e519524SHoward Hinnant              if (++__first == __last)
26913e519524SHoward Hinnant              {
26923e519524SHoward Hinnant                  if (__comp(*__i, *__result.first))
26933e519524SHoward Hinnant                      __result.first = __i;
26943e519524SHoward Hinnant                  else if (!__comp(*__i, *__result.second))
26953e519524SHoward Hinnant                      __result.second = __i;
26963e519524SHoward Hinnant                  break;
26973e519524SHoward Hinnant              }
26983e519524SHoward Hinnant              else
26993e519524SHoward Hinnant              {
27003e519524SHoward Hinnant                  if (__comp(*__first, *__i))
27013e519524SHoward Hinnant                  {
27023e519524SHoward Hinnant                      if (__comp(*__first, *__result.first))
27033e519524SHoward Hinnant                          __result.first = __first;
27043e519524SHoward Hinnant                      if (!__comp(*__i, *__result.second))
27053e519524SHoward Hinnant                          __result.second = __i;
27063e519524SHoward Hinnant                  }
27073e519524SHoward Hinnant                  else
27083e519524SHoward Hinnant                  {
27093e519524SHoward Hinnant                      if (__comp(*__i, *__result.first))
27103e519524SHoward Hinnant                          __result.first = __i;
27113e519524SHoward Hinnant                      if (!__comp(*__first, *__result.second))
27123e519524SHoward Hinnant                          __result.second = __first;
27133e519524SHoward Hinnant                  }
27143e519524SHoward Hinnant              }
27153e519524SHoward Hinnant          }
27163e519524SHoward Hinnant      }
27173e519524SHoward Hinnant  }
27183e519524SHoward Hinnant  return __result;
27193e519524SHoward Hinnant}
27203e519524SHoward Hinnant
27213e519524SHoward Hinnanttemplate <class _ForwardIterator>
27220b0671aeSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27233e519524SHoward Hinnantstd::pair<_ForwardIterator, _ForwardIterator>
27243e519524SHoward Hinnantminmax_element(_ForwardIterator __first, _ForwardIterator __last)
27253e519524SHoward Hinnant{
27269d67c6d5SMarshall Clow    return _VSTD::minmax_element(__first, __last,
27279d67c6d5SMarshall Clow              __less<typename iterator_traits<_ForwardIterator>::value_type>());
27283e519524SHoward Hinnant}
27293e519524SHoward Hinnant
27304eb27b79SHoward Hinnant// minmax
27314eb27b79SHoward Hinnant
27324eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
27339d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27344eb27b79SHoward Hinnantpair<const _Tp&, const _Tp&>
27354eb27b79SHoward Hinnantminmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
27364eb27b79SHoward Hinnant{
27374eb27b79SHoward Hinnant    return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) :
27384eb27b79SHoward Hinnant                              pair<const _Tp&, const _Tp&>(__a, __b);
27394eb27b79SHoward Hinnant}
27404eb27b79SHoward Hinnant
27414eb27b79SHoward Hinnanttemplate<class _Tp>
27429d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27434eb27b79SHoward Hinnantpair<const _Tp&, const _Tp&>
27444eb27b79SHoward Hinnantminmax(const _Tp& __a, const _Tp& __b)
27454eb27b79SHoward Hinnant{
2746ce48a113SHoward Hinnant    return _VSTD::minmax(__a, __b, __less<_Tp>());
27474eb27b79SHoward Hinnant}
27484eb27b79SHoward Hinnant
2749ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
275054976f26SHoward Hinnant
27514eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
27529d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27534eb27b79SHoward Hinnantpair<_Tp, _Tp>
27544eb27b79SHoward Hinnantminmax(initializer_list<_Tp> __t, _Compare __comp)
27554eb27b79SHoward Hinnant{
27569d67c6d5SMarshall Clow    typedef typename initializer_list<_Tp>::const_iterator _Iter;
27579d67c6d5SMarshall Clow    _Iter __first = __t.begin();
27589d67c6d5SMarshall Clow    _Iter __last  = __t.end();
27599d67c6d5SMarshall Clow    std::pair<_Tp, _Tp> __result(*__first, *__first);
27609d67c6d5SMarshall Clow
27619d67c6d5SMarshall Clow    ++__first;
27629d67c6d5SMarshall Clow    if (__t.size() % 2 == 0)
27639d67c6d5SMarshall Clow    {
27649d67c6d5SMarshall Clow        if (__comp(*__first,  __result.first))
27659d67c6d5SMarshall Clow            __result.first  = *__first;
27669d67c6d5SMarshall Clow        else
27679d67c6d5SMarshall Clow            __result.second = *__first;
27689d67c6d5SMarshall Clow        ++__first;
27699d67c6d5SMarshall Clow    }
27709d67c6d5SMarshall Clow
27719d67c6d5SMarshall Clow    while (__first != __last)
27729d67c6d5SMarshall Clow    {
27739d67c6d5SMarshall Clow        _Tp __prev = *__first++;
2774002144f6SMarshall Clow        if (__comp(*__first, __prev)) {
2775002144f6SMarshall Clow            if ( __comp(*__first, __result.first)) __result.first  = *__first;
2776002144f6SMarshall Clow            if (!__comp(__prev, __result.second))  __result.second = __prev;
27779d67c6d5SMarshall Clow            }
27789d67c6d5SMarshall Clow        else {
2779002144f6SMarshall Clow            if ( __comp(__prev, __result.first))    __result.first  = __prev;
2780002144f6SMarshall Clow            if (!__comp(*__first, __result.second)) __result.second = *__first;
27819d67c6d5SMarshall Clow            }
27829d67c6d5SMarshall Clow
27839d67c6d5SMarshall Clow        __first++;
27849d67c6d5SMarshall Clow    }
27859d67c6d5SMarshall Clow    return __result;
27869d67c6d5SMarshall Clow}
27879d67c6d5SMarshall Clow
27889d67c6d5SMarshall Clowtemplate<class _Tp>
27899d67c6d5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27909d67c6d5SMarshall Clowpair<_Tp, _Tp>
27919d67c6d5SMarshall Clowminmax(initializer_list<_Tp> __t)
27929d67c6d5SMarshall Clow{
27939d67c6d5SMarshall Clow    return _VSTD::minmax(__t, __less<_Tp>());
27944eb27b79SHoward Hinnant}
27954eb27b79SHoward Hinnant
2796ddda456aSEric Fiselier#endif  // _LIBCPP_CXX03_LANG
279754976f26SHoward Hinnant
27983e519524SHoward Hinnant// random_shuffle
27993e519524SHoward Hinnant
2800f9d540b0SHoward Hinnant// __independent_bits_engine
2801f9d540b0SHoward Hinnant
2802c003db1fSHoward Hinnanttemplate <unsigned long long _Xp, size_t _Rp>
2803f9d540b0SHoward Hinnantstruct __log2_imp
28043e519524SHoward Hinnant{
2805c003db1fSHoward Hinnant    static const size_t value = _Xp & ((unsigned long long)(1) << _Rp) ? _Rp
2806c003db1fSHoward Hinnant                                           : __log2_imp<_Xp, _Rp - 1>::value;
28073e519524SHoward Hinnant};
28083e519524SHoward Hinnant
2809c003db1fSHoward Hinnanttemplate <unsigned long long _Xp>
2810c003db1fSHoward Hinnantstruct __log2_imp<_Xp, 0>
28113e519524SHoward Hinnant{
2812f9d540b0SHoward Hinnant    static const size_t value = 0;
28133e519524SHoward Hinnant};
28143e519524SHoward Hinnant
2815c003db1fSHoward Hinnanttemplate <size_t _Rp>
2816c003db1fSHoward Hinnantstruct __log2_imp<0, _Rp>
28173e519524SHoward Hinnant{
2818c003db1fSHoward Hinnant    static const size_t value = _Rp + 1;
28193e519524SHoward Hinnant};
28203e519524SHoward Hinnant
282189918caaSEric Fiseliertemplate <class _UIntType, _UIntType _Xp>
2822f9d540b0SHoward Hinnantstruct __log2
28233e519524SHoward Hinnant{
2824c003db1fSHoward Hinnant    static const size_t value = __log2_imp<_Xp,
282589918caaSEric Fiselier                                         sizeof(_UIntType) * __CHAR_BIT__ - 1>::value;
28263e519524SHoward Hinnant};
28273e519524SHoward Hinnant
2828f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2829f9d540b0SHoward Hinnantclass __independent_bits_engine
28303e519524SHoward Hinnant{
2831f9d540b0SHoward Hinnantpublic:
2832f9d540b0SHoward Hinnant    // types
2833f9d540b0SHoward Hinnant    typedef _UIntType result_type;
2834f9d540b0SHoward Hinnant
2835f9d540b0SHoward Hinnantprivate:
2836f9d540b0SHoward Hinnant    typedef typename _Engine::result_type _Engine_result_type;
2837f9d540b0SHoward Hinnant    typedef typename conditional
2838f9d540b0SHoward Hinnant        <
2839f9d540b0SHoward Hinnant            sizeof(_Engine_result_type) <= sizeof(result_type),
2840f9d540b0SHoward Hinnant                result_type,
2841f9d540b0SHoward Hinnant                _Engine_result_type
2842f9d540b0SHoward Hinnant        >::type _Working_result_type;
2843f9d540b0SHoward Hinnant
2844f9d540b0SHoward Hinnant    _Engine& __e_;
2845f9d540b0SHoward Hinnant    size_t __w_;
2846f9d540b0SHoward Hinnant    size_t __w0_;
2847f9d540b0SHoward Hinnant    size_t __n_;
2848f9d540b0SHoward Hinnant    size_t __n0_;
2849f9d540b0SHoward Hinnant    _Working_result_type __y0_;
2850f9d540b0SHoward Hinnant    _Working_result_type __y1_;
2851f9d540b0SHoward Hinnant    _Engine_result_type __mask0_;
2852f9d540b0SHoward Hinnant    _Engine_result_type __mask1_;
2853f9d540b0SHoward Hinnant
2854ddda456aSEric Fiselier#ifdef _LIBCPP_CXX03_LANG
2855c003db1fSHoward Hinnant    static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min
2856f9d540b0SHoward Hinnant                                          + _Working_result_type(1);
2857e386b7b3SHoward Hinnant#else
2858e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min()
2859e386b7b3SHoward Hinnant                                                      + _Working_result_type(1);
2860e386b7b3SHoward Hinnant#endif
2861e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
2862e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
2863e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
2864f9d540b0SHoward Hinnant
2865f9d540b0SHoward Hinnantpublic:
2866f9d540b0SHoward Hinnant    // constructors and seeding functions
2867f9d540b0SHoward Hinnant    __independent_bits_engine(_Engine& __e, size_t __w);
2868f9d540b0SHoward Hinnant
2869f9d540b0SHoward Hinnant    // generating functions
2870c003db1fSHoward Hinnant    result_type operator()() {return __eval(integral_constant<bool, _Rp != 0>());}
2871f9d540b0SHoward Hinnant
2872f9d540b0SHoward Hinnantprivate:
287308bba64aSMarshall Clow    result_type __eval(false_type);
287408bba64aSMarshall Clow    result_type __eval(true_type);
2875f9d540b0SHoward Hinnant};
2876f9d540b0SHoward Hinnant
2877f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2878f9d540b0SHoward Hinnant__independent_bits_engine<_Engine, _UIntType>
2879f9d540b0SHoward Hinnant    ::__independent_bits_engine(_Engine& __e, size_t __w)
2880f9d540b0SHoward Hinnant        : __e_(__e),
2881f9d540b0SHoward Hinnant          __w_(__w)
2882f9d540b0SHoward Hinnant{
2883f9d540b0SHoward Hinnant    __n_ = __w_ / __m + (__w_ % __m != 0);
2884f9d540b0SHoward Hinnant    __w0_ = __w_ / __n_;
2885c003db1fSHoward Hinnant    if (_Rp == 0)
2886c003db1fSHoward Hinnant        __y0_ = _Rp;
2887f9d540b0SHoward Hinnant    else if (__w0_ < _WDt)
2888c003db1fSHoward Hinnant        __y0_ = (_Rp >> __w0_) << __w0_;
2889f9d540b0SHoward Hinnant    else
2890f9d540b0SHoward Hinnant        __y0_ = 0;
2891c003db1fSHoward Hinnant    if (_Rp - __y0_ > __y0_ / __n_)
2892f9d540b0SHoward Hinnant    {
2893f9d540b0SHoward Hinnant        ++__n_;
2894f9d540b0SHoward Hinnant        __w0_ = __w_ / __n_;
2895f9d540b0SHoward Hinnant        if (__w0_ < _WDt)
2896c003db1fSHoward Hinnant            __y0_ = (_Rp >> __w0_) << __w0_;
2897f9d540b0SHoward Hinnant        else
2898f9d540b0SHoward Hinnant            __y0_ = 0;
2899f9d540b0SHoward Hinnant    }
2900f9d540b0SHoward Hinnant    __n0_ = __n_ - __w_ % __n_;
2901f9d540b0SHoward Hinnant    if (__w0_ < _WDt - 1)
2902c003db1fSHoward Hinnant        __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
2903f9d540b0SHoward Hinnant    else
2904f9d540b0SHoward Hinnant        __y1_ = 0;
2905f9d540b0SHoward Hinnant    __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) :
2906f9d540b0SHoward Hinnant                          _Engine_result_type(0);
2907f9d540b0SHoward Hinnant    __mask1_ = __w0_ < _EDt - 1 ?
2908f9d540b0SHoward Hinnant                               _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) :
2909f9d540b0SHoward Hinnant                               _Engine_result_type(~0);
29103e519524SHoward Hinnant}
29113e519524SHoward Hinnant
2912f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2913f9d540b0SHoward Hinnantinline
2914f9d540b0SHoward Hinnant_UIntType
291508bba64aSMarshall Clow__independent_bits_engine<_Engine, _UIntType>::__eval(false_type)
29163e519524SHoward Hinnant{
2917f9d540b0SHoward Hinnant    return static_cast<result_type>(__e_() & __mask0_);
29183e519524SHoward Hinnant}
29193e519524SHoward Hinnant
2920f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2921f9d540b0SHoward Hinnant_UIntType
292208bba64aSMarshall Clow__independent_bits_engine<_Engine, _UIntType>::__eval(true_type)
29233e519524SHoward Hinnant{
29245beb2c3aSMarshall Clow    const size_t _WRt = numeric_limits<result_type>::digits;
2925c003db1fSHoward Hinnant    result_type _Sp = 0;
2926f9d540b0SHoward Hinnant    for (size_t __k = 0; __k < __n0_; ++__k)
2927f9d540b0SHoward Hinnant    {
2928f9d540b0SHoward Hinnant        _Engine_result_type __u;
29293e519524SHoward Hinnant        do
2930f9d540b0SHoward Hinnant        {
2931f9d540b0SHoward Hinnant            __u = __e_() - _Engine::min();
2932f9d540b0SHoward Hinnant        } while (__u >= __y0_);
29335beb2c3aSMarshall Clow        if (__w0_ < _WRt)
2934c003db1fSHoward Hinnant            _Sp <<= __w0_;
2935f9d540b0SHoward Hinnant        else
2936c003db1fSHoward Hinnant            _Sp = 0;
2937c003db1fSHoward Hinnant        _Sp += __u & __mask0_;
2938f9d540b0SHoward Hinnant    }
2939f9d540b0SHoward Hinnant    for (size_t __k = __n0_; __k < __n_; ++__k)
2940f9d540b0SHoward Hinnant    {
2941f9d540b0SHoward Hinnant        _Engine_result_type __u;
2942f9d540b0SHoward Hinnant        do
2943f9d540b0SHoward Hinnant        {
2944f9d540b0SHoward Hinnant            __u = __e_() - _Engine::min();
2945f9d540b0SHoward Hinnant        } while (__u >= __y1_);
29465beb2c3aSMarshall Clow        if (__w0_ < _WRt - 1)
2947c003db1fSHoward Hinnant            _Sp <<= __w0_ + 1;
2948f9d540b0SHoward Hinnant        else
2949c003db1fSHoward Hinnant            _Sp = 0;
2950c003db1fSHoward Hinnant        _Sp += __u & __mask1_;
2951f9d540b0SHoward Hinnant    }
2952c003db1fSHoward Hinnant    return _Sp;
29533e519524SHoward Hinnant}
29543e519524SHoward Hinnant
2955f9d540b0SHoward Hinnant// uniform_int_distribution
29563e519524SHoward Hinnant
2957f9d540b0SHoward Hinnanttemplate<class _IntType = int>
2958f9d540b0SHoward Hinnantclass uniform_int_distribution
29593e519524SHoward Hinnant{
2960f9d540b0SHoward Hinnantpublic:
2961f9d540b0SHoward Hinnant    // types
2962f9d540b0SHoward Hinnant    typedef _IntType result_type;
2963f9d540b0SHoward Hinnant
2964f9d540b0SHoward Hinnant    class param_type
2965f9d540b0SHoward Hinnant    {
2966f9d540b0SHoward Hinnant        result_type __a_;
2967f9d540b0SHoward Hinnant        result_type __b_;
2968f9d540b0SHoward Hinnant    public:
2969f9d540b0SHoward Hinnant        typedef uniform_int_distribution distribution_type;
2970f9d540b0SHoward Hinnant
2971f9d540b0SHoward Hinnant        explicit param_type(result_type __a = 0,
2972f9d540b0SHoward Hinnant                            result_type __b = numeric_limits<result_type>::max())
2973f9d540b0SHoward Hinnant            : __a_(__a), __b_(__b) {}
2974f9d540b0SHoward Hinnant
2975f9d540b0SHoward Hinnant        result_type a() const {return __a_;}
2976f9d540b0SHoward Hinnant        result_type b() const {return __b_;}
2977f9d540b0SHoward Hinnant
2978f9d540b0SHoward Hinnant        friend bool operator==(const param_type& __x, const param_type& __y)
2979f9d540b0SHoward Hinnant            {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;}
2980f9d540b0SHoward Hinnant        friend bool operator!=(const param_type& __x, const param_type& __y)
2981f9d540b0SHoward Hinnant            {return !(__x == __y);}
29823e519524SHoward Hinnant    };
29833e519524SHoward Hinnant
2984f9d540b0SHoward Hinnantprivate:
2985f9d540b0SHoward Hinnant    param_type __p_;
29863e519524SHoward Hinnant
2987f9d540b0SHoward Hinnantpublic:
2988f9d540b0SHoward Hinnant    // constructors and reset functions
2989f9d540b0SHoward Hinnant    explicit uniform_int_distribution(result_type __a = 0,
2990f9d540b0SHoward Hinnant                                      result_type __b = numeric_limits<result_type>::max())
2991f9d540b0SHoward Hinnant        : __p_(param_type(__a, __b)) {}
2992f9d540b0SHoward Hinnant    explicit uniform_int_distribution(const param_type& __p) : __p_(__p) {}
2993f9d540b0SHoward Hinnant    void reset() {}
2994f9d540b0SHoward Hinnant
2995f9d540b0SHoward Hinnant    // generating functions
2996f9d540b0SHoward Hinnant    template<class _URNG> result_type operator()(_URNG& __g)
2997f9d540b0SHoward Hinnant        {return (*this)(__g, __p_);}
2998f9d540b0SHoward Hinnant    template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p);
2999f9d540b0SHoward Hinnant
3000f9d540b0SHoward Hinnant    // property functions
3001f9d540b0SHoward Hinnant    result_type a() const {return __p_.a();}
3002f9d540b0SHoward Hinnant    result_type b() const {return __p_.b();}
3003f9d540b0SHoward Hinnant
3004f9d540b0SHoward Hinnant    param_type param() const {return __p_;}
3005f9d540b0SHoward Hinnant    void param(const param_type& __p) {__p_ = __p;}
3006f9d540b0SHoward Hinnant
3007f9d540b0SHoward Hinnant    result_type min() const {return a();}
3008f9d540b0SHoward Hinnant    result_type max() const {return b();}
3009f9d540b0SHoward Hinnant
3010f9d540b0SHoward Hinnant    friend bool operator==(const uniform_int_distribution& __x,
3011f9d540b0SHoward Hinnant                           const uniform_int_distribution& __y)
3012f9d540b0SHoward Hinnant        {return __x.__p_ == __y.__p_;}
3013f9d540b0SHoward Hinnant    friend bool operator!=(const uniform_int_distribution& __x,
3014f9d540b0SHoward Hinnant                           const uniform_int_distribution& __y)
3015f9d540b0SHoward Hinnant            {return !(__x == __y);}
30163e519524SHoward Hinnant};
30173e519524SHoward Hinnant
3018f9d540b0SHoward Hinnanttemplate<class _IntType>
3019f9d540b0SHoward Hinnanttemplate<class _URNG>
3020f9d540b0SHoward Hinnanttypename uniform_int_distribution<_IntType>::result_type
3021f9d540b0SHoward Hinnantuniform_int_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p)
30223e519524SHoward Hinnant{
3023f9d540b0SHoward Hinnant    typedef typename conditional<sizeof(result_type) <= sizeof(uint32_t),
3024f9d540b0SHoward Hinnant                                            uint32_t, uint64_t>::type _UIntType;
3025c003db1fSHoward Hinnant    const _UIntType _Rp = __p.b() - __p.a() + _UIntType(1);
3026c003db1fSHoward Hinnant    if (_Rp == 1)
3027f9d540b0SHoward Hinnant        return __p.a();
3028f9d540b0SHoward Hinnant    const size_t _Dt = numeric_limits<_UIntType>::digits;
3029f9d540b0SHoward Hinnant    typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
3030c003db1fSHoward Hinnant    if (_Rp == 0)
3031f9d540b0SHoward Hinnant        return static_cast<result_type>(_Eng(__g, _Dt)());
3032c003db1fSHoward Hinnant    size_t __w = _Dt - __clz(_Rp) - 1;
3033a6438ca1SMarshall Clow    if ((_Rp & (std::numeric_limits<_UIntType>::max() >> (_Dt - __w))) != 0)
3034f9d540b0SHoward Hinnant        ++__w;
3035f9d540b0SHoward Hinnant    _Eng __e(__g, __w);
3036f9d540b0SHoward Hinnant    _UIntType __u;
3037f9d540b0SHoward Hinnant    do
30383e519524SHoward Hinnant    {
3039f9d540b0SHoward Hinnant        __u = __e();
3040c003db1fSHoward Hinnant    } while (__u >= _Rp);
3041f9d540b0SHoward Hinnant    return static_cast<result_type>(__u + __p.a());
30423e519524SHoward Hinnant}
3043f9d540b0SHoward Hinnant
304466f1ec46SEric Fiselier#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) \
304566f1ec46SEric Fiselier  || defined(_LIBCPP_BUILDING_LIBRARY)
3046f0544c20SHoward Hinnantclass _LIBCPP_TYPE_VIS __rs_default;
3047f9d540b0SHoward Hinnant
3048f0544c20SHoward Hinnant_LIBCPP_FUNC_VIS __rs_default __rs_get();
3049f9d540b0SHoward Hinnant
3050f0544c20SHoward Hinnantclass _LIBCPP_TYPE_VIS __rs_default
30513e519524SHoward Hinnant{
3052f9d540b0SHoward Hinnant    static unsigned __c_;
3053f9d540b0SHoward Hinnant
3054f9d540b0SHoward Hinnant    __rs_default();
3055f9d540b0SHoward Hinnantpublic:
3056b6e5f854SMarshall Clow    typedef uint_fast32_t result_type;
3057f9d540b0SHoward Hinnant
3058f9d540b0SHoward Hinnant    static const result_type _Min = 0;
3059f9d540b0SHoward Hinnant    static const result_type _Max = 0xFFFFFFFF;
3060f9d540b0SHoward Hinnant
3061f9d540b0SHoward Hinnant    __rs_default(const __rs_default&);
3062f9d540b0SHoward Hinnant    ~__rs_default();
3063f9d540b0SHoward Hinnant
3064f9d540b0SHoward Hinnant    result_type operator()();
3065f9d540b0SHoward Hinnant
3066788c9979SHoward Hinnant    static _LIBCPP_CONSTEXPR result_type min() {return _Min;}
3067788c9979SHoward Hinnant    static _LIBCPP_CONSTEXPR result_type max() {return _Max;}
3068f9d540b0SHoward Hinnant
3069f0544c20SHoward Hinnant    friend _LIBCPP_FUNC_VIS __rs_default __rs_get();
3070f9d540b0SHoward Hinnant};
3071f9d540b0SHoward Hinnant
3072f0544c20SHoward Hinnant_LIBCPP_FUNC_VIS __rs_default __rs_get();
30733e519524SHoward Hinnant
30743e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
30753e519524SHoward Hinnantvoid
30763e519524SHoward Hinnantrandom_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
30773e519524SHoward Hinnant{
30783e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3079c003db1fSHoward Hinnant    typedef uniform_int_distribution<ptrdiff_t> _Dp;
3080c003db1fSHoward Hinnant    typedef typename _Dp::param_type _Pp;
30813e519524SHoward Hinnant    difference_type __d = __last - __first;
30823e519524SHoward Hinnant    if (__d > 1)
30833e519524SHoward Hinnant    {
3084c003db1fSHoward Hinnant        _Dp __uid;
3085f9d540b0SHoward Hinnant        __rs_default __g = __rs_get();
3086f9d540b0SHoward Hinnant        for (--__last, --__d; __first < __last; ++__first, --__d)
3087007b26beSHoward Hinnant        {
3088c003db1fSHoward Hinnant            difference_type __i = __uid(__g, _Pp(0, __d));
3089007b26beSHoward Hinnant            if (__i != difference_type(0))
3090007b26beSHoward Hinnant                swap(*__first, *(__first + __i));
3091007b26beSHoward Hinnant        }
30923e519524SHoward Hinnant    }
30933e519524SHoward Hinnant}
30943e519524SHoward Hinnant
30953e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _RandomNumberGenerator>
30963e519524SHoward Hinnantvoid
30973e519524SHoward Hinnantrandom_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3098ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
30993e519524SHoward Hinnant               _RandomNumberGenerator&& __rand)
31003e519524SHoward Hinnant#else
31013e519524SHoward Hinnant               _RandomNumberGenerator& __rand)
31023e519524SHoward Hinnant#endif
31033e519524SHoward Hinnant{
31043e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
31053e519524SHoward Hinnant    difference_type __d = __last - __first;
31063e519524SHoward Hinnant    if (__d > 1)
31073e519524SHoward Hinnant    {
31083e519524SHoward Hinnant        for (--__last; __first < __last; ++__first, --__d)
3109007b26beSHoward Hinnant        {
3110007b26beSHoward Hinnant            difference_type __i = __rand(__d);
3111007b26beSHoward Hinnant            swap(*__first, *(__first + __i));
3112007b26beSHoward Hinnant        }
31133e519524SHoward Hinnant    }
31143e519524SHoward Hinnant}
31150f37a410SMarshall Clow#endif
31163e519524SHoward Hinnant
3117e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3118e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3119e7154709SEric Fiselier_LIBCPP_INLINE_VISIBILITY
3120e7154709SEric Fiselier_SampleIterator __sample(_PopulationIterator __first,
312142bfedd9SAlexander Richardson                         _PopulationIterator __last, _SampleIterator __output_iter,
3122e7154709SEric Fiselier                         _Distance __n,
3123e7154709SEric Fiselier                         _UniformRandomNumberGenerator & __g,
3124e7154709SEric Fiselier                         input_iterator_tag) {
3125e7154709SEric Fiselier
3126e7154709SEric Fiselier  _Distance __k = 0;
3127e7154709SEric Fiselier  for (; __first != __last && __k < __n; ++__first, (void)++__k)
312842bfedd9SAlexander Richardson    __output_iter[__k] = *__first;
3129e7154709SEric Fiselier  _Distance __sz = __k;
3130e7154709SEric Fiselier  for (; __first != __last; ++__first, (void)++__k) {
3131e7154709SEric Fiselier    _Distance __r = _VSTD::uniform_int_distribution<_Distance>(0, __k)(__g);
3132e7154709SEric Fiselier    if (__r < __sz)
313342bfedd9SAlexander Richardson      __output_iter[__r] = *__first;
3134e7154709SEric Fiselier  }
313542bfedd9SAlexander Richardson  return __output_iter + _VSTD::min(__n, __k);
3136e7154709SEric Fiselier}
3137e7154709SEric Fiselier
3138e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3139e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3140e7154709SEric Fiselier_LIBCPP_INLINE_VISIBILITY
3141e7154709SEric Fiselier_SampleIterator __sample(_PopulationIterator __first,
314242bfedd9SAlexander Richardson                         _PopulationIterator __last, _SampleIterator __output_iter,
3143e7154709SEric Fiselier                         _Distance __n,
3144e7154709SEric Fiselier                         _UniformRandomNumberGenerator& __g,
3145e7154709SEric Fiselier                         forward_iterator_tag) {
3146e7154709SEric Fiselier  _Distance __unsampled_sz = _VSTD::distance(__first, __last);
3147e7154709SEric Fiselier  for (__n = _VSTD::min(__n, __unsampled_sz); __n != 0; ++__first) {
3148e7154709SEric Fiselier    _Distance __r =
3149e7154709SEric Fiselier        _VSTD::uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
3150e7154709SEric Fiselier    if (__r < __n) {
315142bfedd9SAlexander Richardson      *__output_iter++ = *__first;
3152e7154709SEric Fiselier      --__n;
3153e7154709SEric Fiselier    }
3154e7154709SEric Fiselier  }
315542bfedd9SAlexander Richardson  return __output_iter;
3156e7154709SEric Fiselier}
3157e7154709SEric Fiselier
3158e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3159e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3160e7154709SEric Fiselier_LIBCPP_INLINE_VISIBILITY
3161e7154709SEric Fiselier_SampleIterator __sample(_PopulationIterator __first,
316242bfedd9SAlexander Richardson                         _PopulationIterator __last, _SampleIterator __output_iter,
3163e7154709SEric Fiselier                         _Distance __n, _UniformRandomNumberGenerator& __g) {
3164e7154709SEric Fiselier  typedef typename iterator_traits<_PopulationIterator>::iterator_category
3165e7154709SEric Fiselier        _PopCategory;
3166e7154709SEric Fiselier  typedef typename iterator_traits<_PopulationIterator>::difference_type
3167e7154709SEric Fiselier        _Difference;
3168e7154709SEric Fiselier  static_assert(__is_forward_iterator<_PopulationIterator>::value ||
3169e7154709SEric Fiselier                __is_random_access_iterator<_SampleIterator>::value,
3170e7154709SEric Fiselier                "SampleIterator must meet the requirements of RandomAccessIterator");
3171e7154709SEric Fiselier  typedef typename common_type<_Distance, _Difference>::type _CommonType;
3172e7154709SEric Fiselier  _LIBCPP_ASSERT(__n >= 0, "N must be a positive number.");
3173e7154709SEric Fiselier  return _VSTD::__sample(
317442bfedd9SAlexander Richardson      __first, __last, __output_iter, _CommonType(__n),
3175e7154709SEric Fiselier      __g, _PopCategory());
3176e7154709SEric Fiselier}
3177e7154709SEric Fiselier
3178e7154709SEric Fiselier#if _LIBCPP_STD_VER > 14
3179e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3180e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3181e7154709SEric Fiselierinline _LIBCPP_INLINE_VISIBILITY
3182e7154709SEric Fiselier_SampleIterator sample(_PopulationIterator __first,
318342bfedd9SAlexander Richardson                       _PopulationIterator __last, _SampleIterator __output_iter,
3184e7154709SEric Fiselier                       _Distance __n, _UniformRandomNumberGenerator&& __g) {
318542bfedd9SAlexander Richardson    return _VSTD::__sample(__first, __last, __output_iter, __n, __g);
3186e7154709SEric Fiselier}
3187e7154709SEric Fiselier#endif // _LIBCPP_STD_VER > 14
3188e7154709SEric Fiselier
3189f9d540b0SHoward Hinnanttemplate<class _RandomAccessIterator, class _UniformRandomNumberGenerator>
3190f9d540b0SHoward Hinnant    void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3191ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
3192fb340102SHoward Hinnant                 _UniformRandomNumberGenerator&& __g)
3193fb340102SHoward Hinnant#else
3194f9d540b0SHoward Hinnant                 _UniformRandomNumberGenerator& __g)
3195fb340102SHoward Hinnant#endif
3196f9d540b0SHoward Hinnant{
3197f9d540b0SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3198c003db1fSHoward Hinnant    typedef uniform_int_distribution<ptrdiff_t> _Dp;
3199c003db1fSHoward Hinnant    typedef typename _Dp::param_type _Pp;
3200f9d540b0SHoward Hinnant    difference_type __d = __last - __first;
3201f9d540b0SHoward Hinnant    if (__d > 1)
3202f9d540b0SHoward Hinnant    {
3203c003db1fSHoward Hinnant        _Dp __uid;
3204f9d540b0SHoward Hinnant        for (--__last, --__d; __first < __last; ++__first, --__d)
3205007b26beSHoward Hinnant        {
3206c003db1fSHoward Hinnant            difference_type __i = __uid(__g, _Pp(0, __d));
3207007b26beSHoward Hinnant            if (__i != difference_type(0))
3208007b26beSHoward Hinnant                swap(*__first, *(__first + __i));
3209007b26beSHoward Hinnant        }
3210f9d540b0SHoward Hinnant    }
3211f9d540b0SHoward Hinnant}
3212f9d540b0SHoward Hinnant
32133e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
321449c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
32153e519524SHoward Hinnantis_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred)
32163e519524SHoward Hinnant{
32173e519524SHoward Hinnant    for (; __first != __last; ++__first)
32183e519524SHoward Hinnant        if (!__pred(*__first))
32193e519524SHoward Hinnant            break;
3220b9595b79SMarshall Clow    if ( __first == __last )
3221b9595b79SMarshall Clow        return true;
3222b9595b79SMarshall Clow    ++__first;
32233e519524SHoward Hinnant    for (; __first != __last; ++__first)
32243e519524SHoward Hinnant        if (__pred(*__first))
32253e519524SHoward Hinnant            return false;
32263e519524SHoward Hinnant    return true;
32273e519524SHoward Hinnant}
32283e519524SHoward Hinnant
32293e519524SHoward Hinnant// partition
32303e519524SHoward Hinnant
32313e519524SHoward Hinnanttemplate <class _Predicate, class _ForwardIterator>
32323e519524SHoward Hinnant_ForwardIterator
32333e519524SHoward Hinnant__partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag)
32343e519524SHoward Hinnant{
32353e519524SHoward Hinnant    while (true)
32363e519524SHoward Hinnant    {
32373e519524SHoward Hinnant        if (__first == __last)
32383e519524SHoward Hinnant            return __first;
32393e519524SHoward Hinnant        if (!__pred(*__first))
32403e519524SHoward Hinnant            break;
32413e519524SHoward Hinnant        ++__first;
32423e519524SHoward Hinnant    }
32433e519524SHoward Hinnant    for (_ForwardIterator __p = __first; ++__p != __last;)
32443e519524SHoward Hinnant    {
32453e519524SHoward Hinnant        if (__pred(*__p))
32463e519524SHoward Hinnant        {
32473e519524SHoward Hinnant            swap(*__first, *__p);
32483e519524SHoward Hinnant            ++__first;
32493e519524SHoward Hinnant        }
32503e519524SHoward Hinnant    }
32513e519524SHoward Hinnant    return __first;
32523e519524SHoward Hinnant}
32533e519524SHoward Hinnant
32543e519524SHoward Hinnanttemplate <class _Predicate, class _BidirectionalIterator>
32553e519524SHoward Hinnant_BidirectionalIterator
32563e519524SHoward Hinnant__partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
32573e519524SHoward Hinnant            bidirectional_iterator_tag)
32583e519524SHoward Hinnant{
32593e519524SHoward Hinnant    while (true)
32603e519524SHoward Hinnant    {
32613e519524SHoward Hinnant        while (true)
32623e519524SHoward Hinnant        {
32633e519524SHoward Hinnant            if (__first == __last)
32643e519524SHoward Hinnant                return __first;
32653e519524SHoward Hinnant            if (!__pred(*__first))
32663e519524SHoward Hinnant                break;
32673e519524SHoward Hinnant            ++__first;
32683e519524SHoward Hinnant        }
32693e519524SHoward Hinnant        do
32703e519524SHoward Hinnant        {
32713e519524SHoward Hinnant            if (__first == --__last)
32723e519524SHoward Hinnant                return __first;
32733e519524SHoward Hinnant        } while (!__pred(*__last));
32743e519524SHoward Hinnant        swap(*__first, *__last);
32753e519524SHoward Hinnant        ++__first;
32763e519524SHoward Hinnant    }
32773e519524SHoward Hinnant}
32783e519524SHoward Hinnant
32793e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate>
32803e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
32813e519524SHoward Hinnant_ForwardIterator
32823e519524SHoward Hinnantpartition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
32833e519524SHoward Hinnant{
3284ce48a113SHoward Hinnant    return _VSTD::__partition<typename add_lvalue_reference<_Predicate>::type>
32853e519524SHoward Hinnant                            (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
32863e519524SHoward Hinnant}
32873e519524SHoward Hinnant
32883e519524SHoward Hinnant// partition_copy
32893e519524SHoward Hinnant
32903e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator1,
32913e519524SHoward Hinnant          class _OutputIterator2, class _Predicate>
32921b9a4ffdSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_OutputIterator1, _OutputIterator2>
32933e519524SHoward Hinnantpartition_copy(_InputIterator __first, _InputIterator __last,
32943e519524SHoward Hinnant               _OutputIterator1 __out_true, _OutputIterator2 __out_false,
32953e519524SHoward Hinnant               _Predicate __pred)
32963e519524SHoward Hinnant{
32973e519524SHoward Hinnant    for (; __first != __last; ++__first)
32983e519524SHoward Hinnant    {
32993e519524SHoward Hinnant        if (__pred(*__first))
33003e519524SHoward Hinnant        {
33013e519524SHoward Hinnant            *__out_true = *__first;
33023e519524SHoward Hinnant            ++__out_true;
33033e519524SHoward Hinnant        }
33043e519524SHoward Hinnant        else
33053e519524SHoward Hinnant        {
33063e519524SHoward Hinnant            *__out_false = *__first;
33073e519524SHoward Hinnant            ++__out_false;
33083e519524SHoward Hinnant        }
33093e519524SHoward Hinnant    }
33103e519524SHoward Hinnant    return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
33113e519524SHoward Hinnant}
33123e519524SHoward Hinnant
33133e519524SHoward Hinnant// partition_point
33143e519524SHoward Hinnant
33153e519524SHoward Hinnanttemplate<class _ForwardIterator, class _Predicate>
3316674f9128SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
33173e519524SHoward Hinnantpartition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
33183e519524SHoward Hinnant{
33193e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
3320ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
33213e519524SHoward Hinnant    while (__len != 0)
33223e519524SHoward Hinnant    {
33233e519524SHoward Hinnant        difference_type __l2 = __len / 2;
33243e519524SHoward Hinnant        _ForwardIterator __m = __first;
3325ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
33263e519524SHoward Hinnant        if (__pred(*__m))
33273e519524SHoward Hinnant        {
33283e519524SHoward Hinnant            __first = ++__m;
33293e519524SHoward Hinnant            __len -= __l2 + 1;
33303e519524SHoward Hinnant        }
33313e519524SHoward Hinnant        else
33323e519524SHoward Hinnant            __len = __l2;
33333e519524SHoward Hinnant    }
33343e519524SHoward Hinnant    return __first;
33353e519524SHoward Hinnant}
33363e519524SHoward Hinnant
33373e519524SHoward Hinnant// stable_partition
33383e519524SHoward Hinnant
33393e519524SHoward Hinnanttemplate <class _Predicate, class _ForwardIterator, class _Distance, class _Pair>
33403e519524SHoward Hinnant_ForwardIterator
33413e519524SHoward Hinnant__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
33423e519524SHoward Hinnant                   _Distance __len, _Pair __p, forward_iterator_tag __fit)
33433e519524SHoward Hinnant{
33443e519524SHoward Hinnant    // *__first is known to be false
33453e519524SHoward Hinnant    // __len >= 1
33463e519524SHoward Hinnant    if (__len == 1)
33473e519524SHoward Hinnant        return __first;
33483e519524SHoward Hinnant    if (__len == 2)
33493e519524SHoward Hinnant    {
33503e519524SHoward Hinnant        _ForwardIterator __m = __first;
33513e519524SHoward Hinnant        if (__pred(*++__m))
33523e519524SHoward Hinnant        {
33533e519524SHoward Hinnant            swap(*__first, *__m);
33543e519524SHoward Hinnant            return __m;
33553e519524SHoward Hinnant        }
33563e519524SHoward Hinnant        return __first;
33573e519524SHoward Hinnant    }
33583e519524SHoward Hinnant    if (__len <= __p.second)
33593e519524SHoward Hinnant    {   // The buffer is big enough to use
33603e519524SHoward Hinnant        typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
33613e519524SHoward Hinnant        __destruct_n __d(0);
33623e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
33633e519524SHoward Hinnant        // Move the falses into the temporary buffer, and the trues to the front of the line
33643e519524SHoward Hinnant        // Update __first to always point to the end of the trues
33653e519524SHoward Hinnant        value_type* __t = __p.first;
3366ce48a113SHoward Hinnant        ::new(__t) value_type(_VSTD::move(*__first));
33673e519524SHoward Hinnant        __d.__incr((value_type*)0);
33683e519524SHoward Hinnant        ++__t;
33693e519524SHoward Hinnant        _ForwardIterator __i = __first;
33703e519524SHoward Hinnant        while (++__i != __last)
33713e519524SHoward Hinnant        {
33723e519524SHoward Hinnant            if (__pred(*__i))
33733e519524SHoward Hinnant            {
3374ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
33753e519524SHoward Hinnant                ++__first;
33763e519524SHoward Hinnant            }
33773e519524SHoward Hinnant            else
33783e519524SHoward Hinnant            {
3379ce48a113SHoward Hinnant                ::new(__t) value_type(_VSTD::move(*__i));
33803e519524SHoward Hinnant                __d.__incr((value_type*)0);
33813e519524SHoward Hinnant                ++__t;
33823e519524SHoward Hinnant            }
33833e519524SHoward Hinnant        }
33843e519524SHoward Hinnant        // All trues now at start of range, all falses in buffer
33853e519524SHoward Hinnant        // Move falses back into range, but don't mess up __first which points to first false
33863e519524SHoward Hinnant        __i = __first;
33873e519524SHoward Hinnant        for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, ++__i)
3388ce48a113SHoward Hinnant            *__i = _VSTD::move(*__t2);
33893e519524SHoward Hinnant        // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
33903e519524SHoward Hinnant        return __first;
33913e519524SHoward Hinnant    }
33923e519524SHoward Hinnant    // Else not enough buffer, do in place
33933e519524SHoward Hinnant    // __len >= 3
33943e519524SHoward Hinnant    _ForwardIterator __m = __first;
33953e519524SHoward Hinnant    _Distance __len2 = __len / 2;  // __len2 >= 2
3396ce48a113SHoward Hinnant    _VSTD::advance(__m, __len2);
33973e519524SHoward Hinnant    // recurse on [__first, __m), *__first know to be false
33983e519524SHoward Hinnant    // F?????????????????
33993e519524SHoward Hinnant    // f       m         l
34003e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
34013e519524SHoward Hinnant    _ForwardIterator __first_false = __stable_partition<_PredRef>(__first, __m, __pred, __len2, __p, __fit);
34023e519524SHoward Hinnant    // TTTFFFFF??????????
34033e519524SHoward Hinnant    // f  ff   m         l
34043e519524SHoward Hinnant    // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
34053e519524SHoward Hinnant    _ForwardIterator __m1 = __m;
34063e519524SHoward Hinnant    _ForwardIterator __second_false = __last;
34073e519524SHoward Hinnant    _Distance __len_half = __len - __len2;
34083e519524SHoward Hinnant    while (__pred(*__m1))
34093e519524SHoward Hinnant    {
34103e519524SHoward Hinnant        if (++__m1 == __last)
34113e519524SHoward Hinnant            goto __second_half_done;
34123e519524SHoward Hinnant        --__len_half;
34133e519524SHoward Hinnant    }
34143e519524SHoward Hinnant    // TTTFFFFFTTTF??????
34153e519524SHoward Hinnant    // f  ff   m  m1     l
34163e519524SHoward Hinnant    __second_false = __stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __fit);
34173e519524SHoward Hinnant__second_half_done:
34183e519524SHoward Hinnant    // TTTFFFFFTTTTTFFFFF
34193e519524SHoward Hinnant    // f  ff   m    sf   l
3420ce48a113SHoward Hinnant    return _VSTD::rotate(__first_false, __m, __second_false);
34213e519524SHoward Hinnant    // TTTTTTTTFFFFFFFFFF
34223e519524SHoward Hinnant    //         |
34233e519524SHoward Hinnant}
34243e519524SHoward Hinnant
34253e519524SHoward Hinnantstruct __return_temporary_buffer
34263e519524SHoward Hinnant{
34273e519524SHoward Hinnant    template <class _Tp>
3428ce48a113SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::return_temporary_buffer(__p);}
34293e519524SHoward Hinnant};
34303e519524SHoward Hinnant
34313e519524SHoward Hinnanttemplate <class _Predicate, class _ForwardIterator>
34323e519524SHoward Hinnant_ForwardIterator
34333e519524SHoward Hinnant__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
34343e519524SHoward Hinnant                   forward_iterator_tag)
34353e519524SHoward Hinnant{
34363e519524SHoward Hinnant    const unsigned __alloc_limit = 3;  // might want to make this a function of trivial assignment
34373e519524SHoward Hinnant    // Either prove all true and return __first or point to first false
34383e519524SHoward Hinnant    while (true)
34393e519524SHoward Hinnant    {
34403e519524SHoward Hinnant        if (__first == __last)
34413e519524SHoward Hinnant            return __first;
34423e519524SHoward Hinnant        if (!__pred(*__first))
34433e519524SHoward Hinnant            break;
34443e519524SHoward Hinnant        ++__first;
34453e519524SHoward Hinnant    }
34463e519524SHoward Hinnant    // We now have a reduced range [__first, __last)
34473e519524SHoward Hinnant    // *__first is known to be false
34483e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
34493e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3450ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
34513e519524SHoward Hinnant    pair<value_type*, ptrdiff_t> __p(0, 0);
34523e519524SHoward Hinnant    unique_ptr<value_type, __return_temporary_buffer> __h;
34533e519524SHoward Hinnant    if (__len >= __alloc_limit)
34543e519524SHoward Hinnant    {
3455ce48a113SHoward Hinnant        __p = _VSTD::get_temporary_buffer<value_type>(__len);
34563e519524SHoward Hinnant        __h.reset(__p.first);
34573e519524SHoward Hinnant    }
34583e519524SHoward Hinnant    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
34593e519524SHoward Hinnant                             (__first, __last, __pred, __len, __p, forward_iterator_tag());
34603e519524SHoward Hinnant}
34613e519524SHoward Hinnant
34623e519524SHoward Hinnanttemplate <class _Predicate, class _BidirectionalIterator, class _Distance, class _Pair>
34633e519524SHoward Hinnant_BidirectionalIterator
34643e519524SHoward Hinnant__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
34653e519524SHoward Hinnant                   _Distance __len, _Pair __p, bidirectional_iterator_tag __bit)
34663e519524SHoward Hinnant{
34673e519524SHoward Hinnant    // *__first is known to be false
34683e519524SHoward Hinnant    // *__last is known to be true
34693e519524SHoward Hinnant    // __len >= 2
34703e519524SHoward Hinnant    if (__len == 2)
34713e519524SHoward Hinnant    {
34723e519524SHoward Hinnant        swap(*__first, *__last);
34733e519524SHoward Hinnant        return __last;
34743e519524SHoward Hinnant    }
34753e519524SHoward Hinnant    if (__len == 3)
34763e519524SHoward Hinnant    {
34773e519524SHoward Hinnant        _BidirectionalIterator __m = __first;
34783e519524SHoward Hinnant        if (__pred(*++__m))
34793e519524SHoward Hinnant        {
34803e519524SHoward Hinnant            swap(*__first, *__m);
34813e519524SHoward Hinnant            swap(*__m, *__last);
34823e519524SHoward Hinnant            return __last;
34833e519524SHoward Hinnant        }
34843e519524SHoward Hinnant        swap(*__m, *__last);
34853e519524SHoward Hinnant        swap(*__first, *__m);
34863e519524SHoward Hinnant        return __m;
34873e519524SHoward Hinnant    }
34883e519524SHoward Hinnant    if (__len <= __p.second)
34893e519524SHoward Hinnant    {   // The buffer is big enough to use
34903e519524SHoward Hinnant        typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
34913e519524SHoward Hinnant        __destruct_n __d(0);
34923e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
34933e519524SHoward Hinnant        // Move the falses into the temporary buffer, and the trues to the front of the line
34943e519524SHoward Hinnant        // Update __first to always point to the end of the trues
34953e519524SHoward Hinnant        value_type* __t = __p.first;
3496ce48a113SHoward Hinnant        ::new(__t) value_type(_VSTD::move(*__first));
34973e519524SHoward Hinnant        __d.__incr((value_type*)0);
34983e519524SHoward Hinnant        ++__t;
34993e519524SHoward Hinnant        _BidirectionalIterator __i = __first;
35003e519524SHoward Hinnant        while (++__i != __last)
35013e519524SHoward Hinnant        {
35023e519524SHoward Hinnant            if (__pred(*__i))
35033e519524SHoward Hinnant            {
3504ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
35053e519524SHoward Hinnant                ++__first;
35063e519524SHoward Hinnant            }
35073e519524SHoward Hinnant            else
35083e519524SHoward Hinnant            {
3509ce48a113SHoward Hinnant                ::new(__t) value_type(_VSTD::move(*__i));
35103e519524SHoward Hinnant                __d.__incr((value_type*)0);
35113e519524SHoward Hinnant                ++__t;
35123e519524SHoward Hinnant            }
35133e519524SHoward Hinnant        }
35143e519524SHoward Hinnant        // move *__last, known to be true
3515ce48a113SHoward Hinnant        *__first = _VSTD::move(*__i);
35163e519524SHoward Hinnant        __i = ++__first;
35173e519524SHoward Hinnant        // All trues now at start of range, all falses in buffer
35183e519524SHoward Hinnant        // Move falses back into range, but don't mess up __first which points to first false
35193e519524SHoward Hinnant        for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, ++__i)
3520ce48a113SHoward Hinnant            *__i = _VSTD::move(*__t2);
35213e519524SHoward Hinnant        // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
35223e519524SHoward Hinnant        return __first;
35233e519524SHoward Hinnant    }
35243e519524SHoward Hinnant    // Else not enough buffer, do in place
35253e519524SHoward Hinnant    // __len >= 4
35263e519524SHoward Hinnant    _BidirectionalIterator __m = __first;
35273e519524SHoward Hinnant    _Distance __len2 = __len / 2;  // __len2 >= 2
3528ce48a113SHoward Hinnant    _VSTD::advance(__m, __len2);
35293e519524SHoward Hinnant    // recurse on [__first, __m-1], except reduce __m-1 until *(__m-1) is true, *__first know to be false
35303e519524SHoward Hinnant    // F????????????????T
35313e519524SHoward Hinnant    // f       m        l
35323e519524SHoward Hinnant    _BidirectionalIterator __m1 = __m;
35333e519524SHoward Hinnant    _BidirectionalIterator __first_false = __first;
35343e519524SHoward Hinnant    _Distance __len_half = __len2;
35353e519524SHoward Hinnant    while (!__pred(*--__m1))
35363e519524SHoward Hinnant    {
35373e519524SHoward Hinnant        if (__m1 == __first)
35383e519524SHoward Hinnant            goto __first_half_done;
35393e519524SHoward Hinnant        --__len_half;
35403e519524SHoward Hinnant    }
35413e519524SHoward Hinnant    // F???TFFF?????????T
35423e519524SHoward Hinnant    // f   m1  m        l
35433e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
35443e519524SHoward Hinnant    __first_false = __stable_partition<_PredRef>(__first, __m1, __pred, __len_half, __p, __bit);
35453e519524SHoward Hinnant__first_half_done:
35463e519524SHoward Hinnant    // TTTFFFFF?????????T
35473e519524SHoward Hinnant    // f  ff   m        l
35483e519524SHoward Hinnant    // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
35493e519524SHoward Hinnant    __m1 = __m;
35503e519524SHoward Hinnant    _BidirectionalIterator __second_false = __last;
35513e519524SHoward Hinnant    ++__second_false;
35523e519524SHoward Hinnant    __len_half = __len - __len2;
35533e519524SHoward Hinnant    while (__pred(*__m1))
35543e519524SHoward Hinnant    {
35553e519524SHoward Hinnant        if (++__m1 == __last)
35563e519524SHoward Hinnant            goto __second_half_done;
35573e519524SHoward Hinnant        --__len_half;
35583e519524SHoward Hinnant    }
35593e519524SHoward Hinnant    // TTTFFFFFTTTF?????T
35603e519524SHoward Hinnant    // f  ff   m  m1    l
35613e519524SHoward Hinnant    __second_false = __stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __bit);
35623e519524SHoward Hinnant__second_half_done:
35633e519524SHoward Hinnant    // TTTFFFFFTTTTTFFFFF
35643e519524SHoward Hinnant    // f  ff   m    sf  l
3565ce48a113SHoward Hinnant    return _VSTD::rotate(__first_false, __m, __second_false);
35663e519524SHoward Hinnant    // TTTTTTTTFFFFFFFFFF
35673e519524SHoward Hinnant    //         |
35683e519524SHoward Hinnant}
35693e519524SHoward Hinnant
35703e519524SHoward Hinnanttemplate <class _Predicate, class _BidirectionalIterator>
35713e519524SHoward Hinnant_BidirectionalIterator
35723e519524SHoward Hinnant__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
35733e519524SHoward Hinnant                   bidirectional_iterator_tag)
35743e519524SHoward Hinnant{
35753e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
35763e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
35773e519524SHoward Hinnant    const difference_type __alloc_limit = 4;  // might want to make this a function of trivial assignment
35783e519524SHoward Hinnant    // Either prove all true and return __first or point to first false
35793e519524SHoward Hinnant    while (true)
35803e519524SHoward Hinnant    {
35813e519524SHoward Hinnant        if (__first == __last)
35823e519524SHoward Hinnant            return __first;
35833e519524SHoward Hinnant        if (!__pred(*__first))
35843e519524SHoward Hinnant            break;
35853e519524SHoward Hinnant        ++__first;
35863e519524SHoward Hinnant    }
35873e519524SHoward Hinnant    // __first points to first false, everything prior to __first is already set.
35883e519524SHoward Hinnant    // Either prove [__first, __last) is all false and return __first, or point __last to last true
35893e519524SHoward Hinnant    do
35903e519524SHoward Hinnant    {
35913e519524SHoward Hinnant        if (__first == --__last)
35923e519524SHoward Hinnant            return __first;
35933e519524SHoward Hinnant    } while (!__pred(*__last));
35943e519524SHoward Hinnant    // We now have a reduced range [__first, __last]
35953e519524SHoward Hinnant    // *__first is known to be false
35963e519524SHoward Hinnant    // *__last is known to be true
35973e519524SHoward Hinnant    // __len >= 2
3598ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last) + 1;
35993e519524SHoward Hinnant    pair<value_type*, ptrdiff_t> __p(0, 0);
36003e519524SHoward Hinnant    unique_ptr<value_type, __return_temporary_buffer> __h;
36013e519524SHoward Hinnant    if (__len >= __alloc_limit)
36023e519524SHoward Hinnant    {
3603ce48a113SHoward Hinnant        __p = _VSTD::get_temporary_buffer<value_type>(__len);
36043e519524SHoward Hinnant        __h.reset(__p.first);
36053e519524SHoward Hinnant    }
36063e519524SHoward Hinnant    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
36073e519524SHoward Hinnant                             (__first, __last, __pred, __len, __p, bidirectional_iterator_tag());
36083e519524SHoward Hinnant}
36093e519524SHoward Hinnant
36103e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate>
36113e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
36123e519524SHoward Hinnant_ForwardIterator
36133e519524SHoward Hinnantstable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
36143e519524SHoward Hinnant{
36153e519524SHoward Hinnant    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
36163e519524SHoward Hinnant                             (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
36173e519524SHoward Hinnant}
36183e519524SHoward Hinnant
36193e519524SHoward Hinnant// is_sorted_until
36203e519524SHoward Hinnant
36213e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
362249c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
36233e519524SHoward Hinnantis_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
36243e519524SHoward Hinnant{
36253e519524SHoward Hinnant    if (__first != __last)
36263e519524SHoward Hinnant    {
36273e519524SHoward Hinnant        _ForwardIterator __i = __first;
36283e519524SHoward Hinnant        while (++__i != __last)
36293e519524SHoward Hinnant        {
36303e519524SHoward Hinnant            if (__comp(*__i, *__first))
36313e519524SHoward Hinnant                return __i;
36323e519524SHoward Hinnant            __first = __i;
36333e519524SHoward Hinnant        }
36343e519524SHoward Hinnant    }
36353e519524SHoward Hinnant    return __last;
36363e519524SHoward Hinnant}
36373e519524SHoward Hinnant
36383e519524SHoward Hinnanttemplate<class _ForwardIterator>
363949c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36403e519524SHoward Hinnant_ForwardIterator
36413e519524SHoward Hinnantis_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
36423e519524SHoward Hinnant{
3643ce48a113SHoward Hinnant    return _VSTD::is_sorted_until(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
36443e519524SHoward Hinnant}
36453e519524SHoward Hinnant
36463e519524SHoward Hinnant// is_sorted
36473e519524SHoward Hinnant
36483e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
364949c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36503e519524SHoward Hinnantbool
36513e519524SHoward Hinnantis_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
36523e519524SHoward Hinnant{
3653ce48a113SHoward Hinnant    return _VSTD::is_sorted_until(__first, __last, __comp) == __last;
36543e519524SHoward Hinnant}
36553e519524SHoward Hinnant
36563e519524SHoward Hinnanttemplate<class _ForwardIterator>
365749c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36583e519524SHoward Hinnantbool
36593e519524SHoward Hinnantis_sorted(_ForwardIterator __first, _ForwardIterator __last)
36603e519524SHoward Hinnant{
3661ce48a113SHoward Hinnant    return _VSTD::is_sorted(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
36623e519524SHoward Hinnant}
36633e519524SHoward Hinnant
36643e519524SHoward Hinnant// sort
36653e519524SHoward Hinnant
36663e519524SHoward Hinnant// stable, 2-3 compares, 0-2 swaps
36673e519524SHoward Hinnant
36683e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator>
36693e519524SHoward Hinnantunsigned
36703e519524SHoward Hinnant__sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c)
36713e519524SHoward Hinnant{
36723e519524SHoward Hinnant    unsigned __r = 0;
36733e519524SHoward Hinnant    if (!__c(*__y, *__x))          // if x <= y
36743e519524SHoward Hinnant    {
36753e519524SHoward Hinnant        if (!__c(*__z, *__y))      // if y <= z
36763e519524SHoward Hinnant            return __r;            // x <= y && y <= z
36773e519524SHoward Hinnant                                   // x <= y && y > z
36783e519524SHoward Hinnant        swap(*__y, *__z);          // x <= z && y < z
36793e519524SHoward Hinnant        __r = 1;
36803e519524SHoward Hinnant        if (__c(*__y, *__x))       // if x > y
36813e519524SHoward Hinnant        {
36823e519524SHoward Hinnant            swap(*__x, *__y);      // x < y && y <= z
36833e519524SHoward Hinnant            __r = 2;
36843e519524SHoward Hinnant        }
36853e519524SHoward Hinnant        return __r;                // x <= y && y < z
36863e519524SHoward Hinnant    }
36873e519524SHoward Hinnant    if (__c(*__z, *__y))           // x > y, if y > z
36883e519524SHoward Hinnant    {
36893e519524SHoward Hinnant        swap(*__x, *__z);          // x < y && y < z
36903e519524SHoward Hinnant        __r = 1;
36913e519524SHoward Hinnant        return __r;
36923e519524SHoward Hinnant    }
36933e519524SHoward Hinnant    swap(*__x, *__y);              // x > y && y <= z
36943e519524SHoward Hinnant    __r = 1;                       // x < y && x <= z
36953e519524SHoward Hinnant    if (__c(*__z, *__y))           // if y > z
36963e519524SHoward Hinnant    {
36973e519524SHoward Hinnant        swap(*__y, *__z);          // x <= y && y < z
36983e519524SHoward Hinnant        __r = 2;
36993e519524SHoward Hinnant    }
37003e519524SHoward Hinnant    return __r;
37013e519524SHoward Hinnant}                                  // x <= y && y <= z
37023e519524SHoward Hinnant
37033e519524SHoward Hinnant// stable, 3-6 compares, 0-5 swaps
37043e519524SHoward Hinnant
37053e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator>
37063e519524SHoward Hinnantunsigned
37073e519524SHoward Hinnant__sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
37083e519524SHoward Hinnant            _ForwardIterator __x4, _Compare __c)
37093e519524SHoward Hinnant{
37103e519524SHoward Hinnant    unsigned __r = __sort3<_Compare>(__x1, __x2, __x3, __c);
37113e519524SHoward Hinnant    if (__c(*__x4, *__x3))
37123e519524SHoward Hinnant    {
37133e519524SHoward Hinnant        swap(*__x3, *__x4);
37143e519524SHoward Hinnant        ++__r;
37153e519524SHoward Hinnant        if (__c(*__x3, *__x2))
37163e519524SHoward Hinnant        {
37173e519524SHoward Hinnant            swap(*__x2, *__x3);
37183e519524SHoward Hinnant            ++__r;
37193e519524SHoward Hinnant            if (__c(*__x2, *__x1))
37203e519524SHoward Hinnant            {
37213e519524SHoward Hinnant                swap(*__x1, *__x2);
37223e519524SHoward Hinnant                ++__r;
37233e519524SHoward Hinnant            }
37243e519524SHoward Hinnant        }
37253e519524SHoward Hinnant    }
37263e519524SHoward Hinnant    return __r;
37273e519524SHoward Hinnant}
37283e519524SHoward Hinnant
37293e519524SHoward Hinnant// stable, 4-10 compares, 0-9 swaps
37303e519524SHoward Hinnant
37313e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator>
37323e519524SHoward Hinnantunsigned
37333e519524SHoward Hinnant__sort5(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
37343e519524SHoward Hinnant            _ForwardIterator __x4, _ForwardIterator __x5, _Compare __c)
37353e519524SHoward Hinnant{
37363e519524SHoward Hinnant    unsigned __r = __sort4<_Compare>(__x1, __x2, __x3, __x4, __c);
37373e519524SHoward Hinnant    if (__c(*__x5, *__x4))
37383e519524SHoward Hinnant    {
37393e519524SHoward Hinnant        swap(*__x4, *__x5);
37403e519524SHoward Hinnant        ++__r;
37413e519524SHoward Hinnant        if (__c(*__x4, *__x3))
37423e519524SHoward Hinnant        {
37433e519524SHoward Hinnant            swap(*__x3, *__x4);
37443e519524SHoward Hinnant            ++__r;
37453e519524SHoward Hinnant            if (__c(*__x3, *__x2))
37463e519524SHoward Hinnant            {
37473e519524SHoward Hinnant                swap(*__x2, *__x3);
37483e519524SHoward Hinnant                ++__r;
37493e519524SHoward Hinnant                if (__c(*__x2, *__x1))
37503e519524SHoward Hinnant                {
37513e519524SHoward Hinnant                    swap(*__x1, *__x2);
37523e519524SHoward Hinnant                    ++__r;
37533e519524SHoward Hinnant                }
37543e519524SHoward Hinnant            }
37553e519524SHoward Hinnant        }
37563e519524SHoward Hinnant    }
37573e519524SHoward Hinnant    return __r;
37583e519524SHoward Hinnant}
37593e519524SHoward Hinnant
37603e519524SHoward Hinnant// Assumes size > 0
37613e519524SHoward Hinnanttemplate <class _Compare, class _BirdirectionalIterator>
37623e519524SHoward Hinnantvoid
37633e519524SHoward Hinnant__selection_sort(_BirdirectionalIterator __first, _BirdirectionalIterator __last, _Compare __comp)
37643e519524SHoward Hinnant{
37653e519524SHoward Hinnant    _BirdirectionalIterator __lm1 = __last;
37663e519524SHoward Hinnant    for (--__lm1; __first != __lm1; ++__first)
37673e519524SHoward Hinnant    {
3768ce48a113SHoward Hinnant        _BirdirectionalIterator __i = _VSTD::min_element<_BirdirectionalIterator,
37693e519524SHoward Hinnant                                                        typename add_lvalue_reference<_Compare>::type>
37703e519524SHoward Hinnant                                                       (__first, __last, __comp);
37713e519524SHoward Hinnant        if (__i != __first)
37723e519524SHoward Hinnant            swap(*__first, *__i);
37733e519524SHoward Hinnant    }
37743e519524SHoward Hinnant}
37753e519524SHoward Hinnant
37763e519524SHoward Hinnanttemplate <class _Compare, class _BirdirectionalIterator>
37773e519524SHoward Hinnantvoid
37783e519524SHoward Hinnant__insertion_sort(_BirdirectionalIterator __first, _BirdirectionalIterator __last, _Compare __comp)
37793e519524SHoward Hinnant{
37803e519524SHoward Hinnant    typedef typename iterator_traits<_BirdirectionalIterator>::value_type value_type;
37813e519524SHoward Hinnant    if (__first != __last)
37823e519524SHoward Hinnant    {
37833e519524SHoward Hinnant        _BirdirectionalIterator __i = __first;
37843e519524SHoward Hinnant        for (++__i; __i != __last; ++__i)
37853e519524SHoward Hinnant        {
37863e519524SHoward Hinnant            _BirdirectionalIterator __j = __i;
3787ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__j));
37883e519524SHoward Hinnant            for (_BirdirectionalIterator __k = __i; __k != __first && __comp(__t,  *--__k); --__j)
3789ce48a113SHoward Hinnant                *__j = _VSTD::move(*__k);
3790ce48a113SHoward Hinnant            *__j = _VSTD::move(__t);
37913e519524SHoward Hinnant        }
37923e519524SHoward Hinnant    }
37933e519524SHoward Hinnant}
37943e519524SHoward Hinnant
37953e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
37963e519524SHoward Hinnantvoid
37973e519524SHoward Hinnant__insertion_sort_3(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
37983e519524SHoward Hinnant{
37993e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
38003e519524SHoward Hinnant    _RandomAccessIterator __j = __first+2;
38013e519524SHoward Hinnant    __sort3<_Compare>(__first, __first+1, __j, __comp);
38023e519524SHoward Hinnant    for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
38033e519524SHoward Hinnant    {
38043e519524SHoward Hinnant        if (__comp(*__i, *__j))
38053e519524SHoward Hinnant        {
3806ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__i));
38073e519524SHoward Hinnant            _RandomAccessIterator __k = __j;
38083e519524SHoward Hinnant            __j = __i;
38093e519524SHoward Hinnant            do
38103e519524SHoward Hinnant            {
3811ce48a113SHoward Hinnant                *__j = _VSTD::move(*__k);
38123e519524SHoward Hinnant                __j = __k;
38133e519524SHoward Hinnant            } while (__j != __first && __comp(__t, *--__k));
3814ce48a113SHoward Hinnant            *__j = _VSTD::move(__t);
38153e519524SHoward Hinnant        }
38163e519524SHoward Hinnant        __j = __i;
38173e519524SHoward Hinnant    }
38183e519524SHoward Hinnant}
38193e519524SHoward Hinnant
38203e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
38213e519524SHoward Hinnantbool
38223e519524SHoward Hinnant__insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
38233e519524SHoward Hinnant{
38243e519524SHoward Hinnant    switch (__last - __first)
38253e519524SHoward Hinnant    {
38263e519524SHoward Hinnant    case 0:
38273e519524SHoward Hinnant    case 1:
38283e519524SHoward Hinnant        return true;
38293e519524SHoward Hinnant    case 2:
38303e519524SHoward Hinnant        if (__comp(*--__last, *__first))
38313e519524SHoward Hinnant            swap(*__first, *__last);
38323e519524SHoward Hinnant        return true;
38333e519524SHoward Hinnant    case 3:
3834ce48a113SHoward Hinnant        _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
38353e519524SHoward Hinnant        return true;
38363e519524SHoward Hinnant    case 4:
3837ce48a113SHoward Hinnant        _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
38383e519524SHoward Hinnant        return true;
38393e519524SHoward Hinnant    case 5:
3840ce48a113SHoward Hinnant        _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
38413e519524SHoward Hinnant        return true;
38423e519524SHoward Hinnant    }
38433e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
38443e519524SHoward Hinnant    _RandomAccessIterator __j = __first+2;
38453e519524SHoward Hinnant    __sort3<_Compare>(__first, __first+1, __j, __comp);
38463e519524SHoward Hinnant    const unsigned __limit = 8;
38473e519524SHoward Hinnant    unsigned __count = 0;
38483e519524SHoward Hinnant    for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
38493e519524SHoward Hinnant    {
38503e519524SHoward Hinnant        if (__comp(*__i, *__j))
38513e519524SHoward Hinnant        {
3852ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__i));
38533e519524SHoward Hinnant            _RandomAccessIterator __k = __j;
38543e519524SHoward Hinnant            __j = __i;
38553e519524SHoward Hinnant            do
38563e519524SHoward Hinnant            {
3857ce48a113SHoward Hinnant                *__j = _VSTD::move(*__k);
38583e519524SHoward Hinnant                __j = __k;
38593e519524SHoward Hinnant            } while (__j != __first && __comp(__t, *--__k));
3860ce48a113SHoward Hinnant            *__j = _VSTD::move(__t);
38613e519524SHoward Hinnant            if (++__count == __limit)
38623e519524SHoward Hinnant                return ++__i == __last;
38633e519524SHoward Hinnant        }
38643e519524SHoward Hinnant        __j = __i;
38653e519524SHoward Hinnant    }
38663e519524SHoward Hinnant    return true;
38673e519524SHoward Hinnant}
38683e519524SHoward Hinnant
38693e519524SHoward Hinnanttemplate <class _Compare, class _BirdirectionalIterator>
38703e519524SHoward Hinnantvoid
38713e519524SHoward Hinnant__insertion_sort_move(_BirdirectionalIterator __first1, _BirdirectionalIterator __last1,
38723e519524SHoward Hinnant                      typename iterator_traits<_BirdirectionalIterator>::value_type* __first2, _Compare __comp)
38733e519524SHoward Hinnant{
38743e519524SHoward Hinnant    typedef typename iterator_traits<_BirdirectionalIterator>::value_type value_type;
38753e519524SHoward Hinnant    if (__first1 != __last1)
38763e519524SHoward Hinnant    {
38773e519524SHoward Hinnant        __destruct_n __d(0);
38783e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h(__first2, __d);
38793e519524SHoward Hinnant        value_type* __last2 = __first2;
3880ce48a113SHoward Hinnant        ::new(__last2) value_type(_VSTD::move(*__first1));
38813e519524SHoward Hinnant        __d.__incr((value_type*)0);
38823e519524SHoward Hinnant        for (++__last2; ++__first1 != __last1; ++__last2)
38833e519524SHoward Hinnant        {
38843e519524SHoward Hinnant            value_type* __j2 = __last2;
38853e519524SHoward Hinnant            value_type* __i2 = __j2;
38863e519524SHoward Hinnant            if (__comp(*__first1, *--__i2))
38873e519524SHoward Hinnant            {
3888ce48a113SHoward Hinnant                ::new(__j2) value_type(_VSTD::move(*__i2));
38893e519524SHoward Hinnant                __d.__incr((value_type*)0);
38903e519524SHoward Hinnant                for (--__j2; __i2 != __first2 && __comp(*__first1,  *--__i2); --__j2)
3891ce48a113SHoward Hinnant                    *__j2 = _VSTD::move(*__i2);
3892ce48a113SHoward Hinnant                *__j2 = _VSTD::move(*__first1);
38933e519524SHoward Hinnant            }
38943e519524SHoward Hinnant            else
38953e519524SHoward Hinnant            {
3896ce48a113SHoward Hinnant                ::new(__j2) value_type(_VSTD::move(*__first1));
38973e519524SHoward Hinnant                __d.__incr((value_type*)0);
38983e519524SHoward Hinnant            }
38993e519524SHoward Hinnant        }
39003e519524SHoward Hinnant        __h.release();
39013e519524SHoward Hinnant    }
39023e519524SHoward Hinnant}
39033e519524SHoward Hinnant
39043e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
39053e519524SHoward Hinnantvoid
39063e519524SHoward Hinnant__sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
39073e519524SHoward Hinnant{
39083e519524SHoward Hinnant    // _Compare is known to be a reference type
39093e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
39103e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
3911ca740483SHoward Hinnant    const difference_type __limit = is_trivially_copy_constructible<value_type>::value &&
3912ca740483SHoward Hinnant                                    is_trivially_copy_assignable<value_type>::value ? 30 : 6;
39133e519524SHoward Hinnant    while (true)
39143e519524SHoward Hinnant    {
39153e519524SHoward Hinnant    __restart:
39163e519524SHoward Hinnant        difference_type __len = __last - __first;
39173e519524SHoward Hinnant        switch (__len)
39183e519524SHoward Hinnant        {
39193e519524SHoward Hinnant        case 0:
39203e519524SHoward Hinnant        case 1:
39213e519524SHoward Hinnant            return;
39223e519524SHoward Hinnant        case 2:
39233e519524SHoward Hinnant            if (__comp(*--__last, *__first))
39243e519524SHoward Hinnant                swap(*__first, *__last);
39253e519524SHoward Hinnant            return;
39263e519524SHoward Hinnant        case 3:
3927ce48a113SHoward Hinnant            _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
39283e519524SHoward Hinnant            return;
39293e519524SHoward Hinnant        case 4:
3930ce48a113SHoward Hinnant            _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
39313e519524SHoward Hinnant            return;
39323e519524SHoward Hinnant        case 5:
3933ce48a113SHoward Hinnant            _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
39343e519524SHoward Hinnant            return;
39353e519524SHoward Hinnant        }
39363e519524SHoward Hinnant        if (__len <= __limit)
39373e519524SHoward Hinnant        {
3938ce48a113SHoward Hinnant            _VSTD::__insertion_sort_3<_Compare>(__first, __last, __comp);
39393e519524SHoward Hinnant            return;
39403e519524SHoward Hinnant        }
39413e519524SHoward Hinnant        // __len > 5
39423e519524SHoward Hinnant        _RandomAccessIterator __m = __first;
39433e519524SHoward Hinnant        _RandomAccessIterator __lm1 = __last;
39443e519524SHoward Hinnant        --__lm1;
39453e519524SHoward Hinnant        unsigned __n_swaps;
39463e519524SHoward Hinnant        {
39473e519524SHoward Hinnant        difference_type __delta;
39483e519524SHoward Hinnant        if (__len >= 1000)
39493e519524SHoward Hinnant        {
39503e519524SHoward Hinnant            __delta = __len/2;
39513e519524SHoward Hinnant            __m += __delta;
39523e519524SHoward Hinnant            __delta /= 2;
3953ce48a113SHoward Hinnant            __n_swaps = _VSTD::__sort5<_Compare>(__first, __first + __delta, __m, __m+__delta, __lm1, __comp);
39543e519524SHoward Hinnant        }
39553e519524SHoward Hinnant        else
39563e519524SHoward Hinnant        {
39573e519524SHoward Hinnant            __delta = __len/2;
39583e519524SHoward Hinnant            __m += __delta;
3959ce48a113SHoward Hinnant            __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, __lm1, __comp);
39603e519524SHoward Hinnant        }
39613e519524SHoward Hinnant        }
39623e519524SHoward Hinnant        // *__m is median
39633e519524SHoward Hinnant        // partition [__first, __m) < *__m and *__m <= [__m, __last)
39643e519524SHoward Hinnant        // (this inhibits tossing elements equivalent to __m around unnecessarily)
39653e519524SHoward Hinnant        _RandomAccessIterator __i = __first;
39663e519524SHoward Hinnant        _RandomAccessIterator __j = __lm1;
39673e519524SHoward Hinnant        // j points beyond range to be tested, *__m is known to be <= *__lm1
39683e519524SHoward Hinnant        // The search going up is known to be guarded but the search coming down isn't.
39693e519524SHoward Hinnant        // Prime the downward search with a guard.
39703e519524SHoward Hinnant        if (!__comp(*__i, *__m))  // if *__first == *__m
39713e519524SHoward Hinnant        {
39723e519524SHoward Hinnant            // *__first == *__m, *__first doesn't go in first part
39733e519524SHoward Hinnant            // manually guard downward moving __j against __i
39743e519524SHoward Hinnant            while (true)
39753e519524SHoward Hinnant            {
39763e519524SHoward Hinnant                if (__i == --__j)
39773e519524SHoward Hinnant                {
39783e519524SHoward Hinnant                    // *__first == *__m, *__m <= all other elements
39793e519524SHoward Hinnant                    // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
39803e519524SHoward Hinnant                    ++__i;  // __first + 1
39813e519524SHoward Hinnant                    __j = __last;
39823e519524SHoward Hinnant                    if (!__comp(*__first, *--__j))  // we need a guard if *__first == *(__last-1)
39833e519524SHoward Hinnant                    {
39843e519524SHoward Hinnant                        while (true)
39853e519524SHoward Hinnant                        {
39863e519524SHoward Hinnant                            if (__i == __j)
39873e519524SHoward Hinnant                                return;  // [__first, __last) all equivalent elements
39883e519524SHoward Hinnant                            if (__comp(*__first, *__i))
39893e519524SHoward Hinnant                            {
39903e519524SHoward Hinnant                                swap(*__i, *__j);
39913e519524SHoward Hinnant                                ++__n_swaps;
39923e519524SHoward Hinnant                                ++__i;
39933e519524SHoward Hinnant                                break;
39943e519524SHoward Hinnant                            }
39953e519524SHoward Hinnant                            ++__i;
39963e519524SHoward Hinnant                        }
39973e519524SHoward Hinnant                    }
39983e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
39993e519524SHoward Hinnant                    if (__i == __j)
40003e519524SHoward Hinnant                        return;
40013e519524SHoward Hinnant                    while (true)
40023e519524SHoward Hinnant                    {
40033e519524SHoward Hinnant                        while (!__comp(*__first, *__i))
40043e519524SHoward Hinnant                            ++__i;
40053e519524SHoward Hinnant                        while (__comp(*__first, *--__j))
40063e519524SHoward Hinnant                            ;
40073e519524SHoward Hinnant                        if (__i >= __j)
40083e519524SHoward Hinnant                            break;
40093e519524SHoward Hinnant                        swap(*__i, *__j);
40103e519524SHoward Hinnant                        ++__n_swaps;
40113e519524SHoward Hinnant                        ++__i;
40123e519524SHoward Hinnant                    }
40133e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__i, __last)
40143e519524SHoward Hinnant                    // The first part is sorted, sort the secod part
4015ce48a113SHoward Hinnant                    // _VSTD::__sort<_Compare>(__i, __last, __comp);
40163e519524SHoward Hinnant                    __first = __i;
40173e519524SHoward Hinnant                    goto __restart;
40183e519524SHoward Hinnant                }
40193e519524SHoward Hinnant                if (__comp(*__j, *__m))
40203e519524SHoward Hinnant                {
40213e519524SHoward Hinnant                    swap(*__i, *__j);
40223e519524SHoward Hinnant                    ++__n_swaps;
40233e519524SHoward Hinnant                    break;  // found guard for downward moving __j, now use unguarded partition
40243e519524SHoward Hinnant                }
40253e519524SHoward Hinnant            }
40263e519524SHoward Hinnant        }
40273e519524SHoward Hinnant        // It is known that *__i < *__m
40283e519524SHoward Hinnant        ++__i;
40293e519524SHoward Hinnant        // j points beyond range to be tested, *__m is known to be <= *__lm1
40303e519524SHoward Hinnant        // if not yet partitioned...
40313e519524SHoward Hinnant        if (__i < __j)
40323e519524SHoward Hinnant        {
40333e519524SHoward Hinnant            // known that *(__i - 1) < *__m
40343e519524SHoward Hinnant            // known that __i <= __m
40353e519524SHoward Hinnant            while (true)
40363e519524SHoward Hinnant            {
40373e519524SHoward Hinnant                // __m still guards upward moving __i
40383e519524SHoward Hinnant                while (__comp(*__i, *__m))
40393e519524SHoward Hinnant                    ++__i;
40403e519524SHoward Hinnant                // It is now known that a guard exists for downward moving __j
40413e519524SHoward Hinnant                while (!__comp(*--__j, *__m))
40423e519524SHoward Hinnant                    ;
40433e519524SHoward Hinnant                if (__i > __j)
40443e519524SHoward Hinnant                    break;
40453e519524SHoward Hinnant                swap(*__i, *__j);
40463e519524SHoward Hinnant                ++__n_swaps;
40473e519524SHoward Hinnant                // It is known that __m != __j
40483e519524SHoward Hinnant                // If __m just moved, follow it
40493e519524SHoward Hinnant                if (__m == __i)
40503e519524SHoward Hinnant                    __m = __j;
40513e519524SHoward Hinnant                ++__i;
40523e519524SHoward Hinnant            }
40533e519524SHoward Hinnant        }
40543e519524SHoward Hinnant        // [__first, __i) < *__m and *__m <= [__i, __last)
40553e519524SHoward Hinnant        if (__i != __m && __comp(*__m, *__i))
40563e519524SHoward Hinnant        {
40573e519524SHoward Hinnant            swap(*__i, *__m);
40583e519524SHoward Hinnant            ++__n_swaps;
40593e519524SHoward Hinnant        }
40603e519524SHoward Hinnant        // [__first, __i) < *__i and *__i <= [__i+1, __last)
40613e519524SHoward Hinnant        // If we were given a perfect partition, see if insertion sort is quick...
40623e519524SHoward Hinnant        if (__n_swaps == 0)
40633e519524SHoward Hinnant        {
4064ce48a113SHoward Hinnant            bool __fs = _VSTD::__insertion_sort_incomplete<_Compare>(__first, __i, __comp);
4065ce48a113SHoward Hinnant            if (_VSTD::__insertion_sort_incomplete<_Compare>(__i+1, __last, __comp))
40663e519524SHoward Hinnant            {
40673e519524SHoward Hinnant                if (__fs)
40683e519524SHoward Hinnant                    return;
40693e519524SHoward Hinnant                __last = __i;
40703e519524SHoward Hinnant                continue;
40713e519524SHoward Hinnant            }
40723e519524SHoward Hinnant            else
40733e519524SHoward Hinnant            {
40743e519524SHoward Hinnant                if (__fs)
40753e519524SHoward Hinnant                {
40763e519524SHoward Hinnant                    __first = ++__i;
40773e519524SHoward Hinnant                    continue;
40783e519524SHoward Hinnant                }
40793e519524SHoward Hinnant            }
40803e519524SHoward Hinnant        }
40813e519524SHoward Hinnant        // sort smaller range with recursive call and larger with tail recursion elimination
40823e519524SHoward Hinnant        if (__i - __first < __last - __i)
40833e519524SHoward Hinnant        {
4084ce48a113SHoward Hinnant            _VSTD::__sort<_Compare>(__first, __i, __comp);
4085ce48a113SHoward Hinnant            // _VSTD::__sort<_Compare>(__i+1, __last, __comp);
40863e519524SHoward Hinnant            __first = ++__i;
40873e519524SHoward Hinnant        }
40883e519524SHoward Hinnant        else
40893e519524SHoward Hinnant        {
4090ce48a113SHoward Hinnant            _VSTD::__sort<_Compare>(__i+1, __last, __comp);
4091ce48a113SHoward Hinnant            // _VSTD::__sort<_Compare>(__first, __i, __comp);
40923e519524SHoward Hinnant            __last = __i;
40933e519524SHoward Hinnant        }
40943e519524SHoward Hinnant    }
40953e519524SHoward Hinnant}
40963e519524SHoward Hinnant
40973e519524SHoward Hinnant// This forwarder keeps the top call and the recursive calls using the same instantiation, forcing a reference _Compare
40983e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
40993e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41003e519524SHoward Hinnantvoid
41013e519524SHoward Hinnantsort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
41023e519524SHoward Hinnant{
4103145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
41043e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
41053e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
41063e519524SHoward Hinnant    __sort<_Comp_ref>(__first, __last, __c);
4107145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
41083e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
41093e519524SHoward Hinnant    __sort<_Comp_ref>(__first, __last, __comp);
4110145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
41113e519524SHoward Hinnant}
41123e519524SHoward Hinnant
41133e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
41143e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41153e519524SHoward Hinnantvoid
41163e519524SHoward Hinnantsort(_RandomAccessIterator __first, _RandomAccessIterator __last)
41173e519524SHoward Hinnant{
4118ce48a113SHoward Hinnant    _VSTD::sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
41193e519524SHoward Hinnant}
41203e519524SHoward Hinnant
41213e519524SHoward Hinnanttemplate <class _Tp>
41223e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41233e519524SHoward Hinnantvoid
41243e519524SHoward Hinnantsort(_Tp** __first, _Tp** __last)
41253e519524SHoward Hinnant{
4126ce48a113SHoward Hinnant    _VSTD::sort((size_t*)__first, (size_t*)__last, __less<size_t>());
41273e519524SHoward Hinnant}
41283e519524SHoward Hinnant
41293e519524SHoward Hinnanttemplate <class _Tp>
41303e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41313e519524SHoward Hinnantvoid
41323e519524SHoward Hinnantsort(__wrap_iter<_Tp*> __first, __wrap_iter<_Tp*> __last)
41333e519524SHoward Hinnant{
4134ce48a113SHoward Hinnant    _VSTD::sort(__first.base(), __last.base());
41353e519524SHoward Hinnant}
41363e519524SHoward Hinnant
4137f554add5SHoward Hinnanttemplate <class _Tp, class _Compare>
4138f554add5SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
4139f554add5SHoward Hinnantvoid
4140f554add5SHoward Hinnantsort(__wrap_iter<_Tp*> __first, __wrap_iter<_Tp*> __last, _Compare __comp)
4141f554add5SHoward Hinnant{
4142f554add5SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4143f554add5SHoward Hinnant    _VSTD::sort<_Tp*, _Comp_ref>(__first.base(), __last.base(), __comp);
4144f554add5SHoward Hinnant}
4145f554add5SHoward Hinnant
4146f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<char>&, char*>(char*, char*, __less<char>&))
4147f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
4148f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
4149f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
4150f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<short>&, short*>(short*, short*, __less<short>&))
4151f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
4152f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<int>&, int*>(int*, int*, __less<int>&))
4153f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
4154f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long>&, long*>(long*, long*, __less<long>&))
4155f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
4156f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
4157f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
4158f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<float>&, float*>(float*, float*, __less<float>&))
4159f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<double>&, double*>(double*, double*, __less<double>&))
4160f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
41613e519524SHoward Hinnant
4162f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<char>&, char*>(char*, char*, __less<char>&))
4163f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
4164f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
4165f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
4166f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<short>&, short*>(short*, short*, __less<short>&))
4167f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
4168f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<int>&, int*>(int*, int*, __less<int>&))
4169f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
4170f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long>&, long*>(long*, long*, __less<long>&))
4171f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
4172f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
4173f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
4174f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<float>&, float*>(float*, float*, __less<float>&))
4175f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<double>&, double*>(double*, double*, __less<double>&))
4176f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
41773e519524SHoward Hinnant
4178f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS unsigned __sort5<__less<long double>&, long double*>(long double*, long double*, long double*, long double*, long double*, __less<long double>&))
41793e519524SHoward Hinnant
41803e519524SHoward Hinnant// lower_bound
41813e519524SHoward Hinnant
41823e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4183d57c03ddSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
4184e4383379SHoward Hinnant__lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
41853e519524SHoward Hinnant{
41863e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4187ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
41883e519524SHoward Hinnant    while (__len != 0)
41893e519524SHoward Hinnant    {
41903e519524SHoward Hinnant        difference_type __l2 = __len / 2;
41913e519524SHoward Hinnant        _ForwardIterator __m = __first;
4192ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
4193e4383379SHoward Hinnant        if (__comp(*__m, __value_))
41943e519524SHoward Hinnant        {
41953e519524SHoward Hinnant            __first = ++__m;
41963e519524SHoward Hinnant            __len -= __l2 + 1;
41973e519524SHoward Hinnant        }
41983e519524SHoward Hinnant        else
41993e519524SHoward Hinnant            __len = __l2;
42003e519524SHoward Hinnant    }
42013e519524SHoward Hinnant    return __first;
42023e519524SHoward Hinnant}
42033e519524SHoward Hinnant
42043e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
4205d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42063e519524SHoward Hinnant_ForwardIterator
4207e4383379SHoward Hinnantlower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42083e519524SHoward Hinnant{
4209145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
42103e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
42113e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
4212e4383379SHoward Hinnant    return __lower_bound<_Comp_ref>(__first, __last, __value_, __c);
4213145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
42143e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4215e4383379SHoward Hinnant    return __lower_bound<_Comp_ref>(__first, __last, __value_, __comp);
4216145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
42173e519524SHoward Hinnant}
42183e519524SHoward Hinnant
42193e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
4220d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42213e519524SHoward Hinnant_ForwardIterator
4222e4383379SHoward Hinnantlower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
42233e519524SHoward Hinnant{
4224e4383379SHoward Hinnant    return _VSTD::lower_bound(__first, __last, __value_,
42253e519524SHoward Hinnant                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
42263e519524SHoward Hinnant}
42273e519524SHoward Hinnant
42283e519524SHoward Hinnant// upper_bound
42293e519524SHoward Hinnant
42303e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4231d57c03ddSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
4232e4383379SHoward Hinnant__upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42333e519524SHoward Hinnant{
42343e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4235ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
42363e519524SHoward Hinnant    while (__len != 0)
42373e519524SHoward Hinnant    {
42383e519524SHoward Hinnant        difference_type __l2 = __len / 2;
42393e519524SHoward Hinnant        _ForwardIterator __m = __first;
4240ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
4241e4383379SHoward Hinnant        if (__comp(__value_, *__m))
42423e519524SHoward Hinnant            __len = __l2;
42433e519524SHoward Hinnant        else
42443e519524SHoward Hinnant        {
42453e519524SHoward Hinnant            __first = ++__m;
42463e519524SHoward Hinnant            __len -= __l2 + 1;
42473e519524SHoward Hinnant        }
42483e519524SHoward Hinnant    }
42493e519524SHoward Hinnant    return __first;
42503e519524SHoward Hinnant}
42513e519524SHoward Hinnant
42523e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
4253d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42543e519524SHoward Hinnant_ForwardIterator
4255e4383379SHoward Hinnantupper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42563e519524SHoward Hinnant{
4257145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
42583e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
42593e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
4260e4383379SHoward Hinnant    return __upper_bound<_Comp_ref>(__first, __last, __value_, __c);
4261145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
42623e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4263e4383379SHoward Hinnant    return __upper_bound<_Comp_ref>(__first, __last, __value_, __comp);
4264145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
42653e519524SHoward Hinnant}
42663e519524SHoward Hinnant
42673e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
4268d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42693e519524SHoward Hinnant_ForwardIterator
4270e4383379SHoward Hinnantupper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
42713e519524SHoward Hinnant{
4272e4383379SHoward Hinnant    return _VSTD::upper_bound(__first, __last, __value_,
42733e519524SHoward Hinnant                             __less<_Tp, typename iterator_traits<_ForwardIterator>::value_type>());
42743e519524SHoward Hinnant}
42753e519524SHoward Hinnant
42763e519524SHoward Hinnant// equal_range
42773e519524SHoward Hinnant
42783e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4279d57c03ddSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_ForwardIterator, _ForwardIterator>
4280e4383379SHoward Hinnant__equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42813e519524SHoward Hinnant{
42823e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4283ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
42843e519524SHoward Hinnant    while (__len != 0)
42853e519524SHoward Hinnant    {
42863e519524SHoward Hinnant        difference_type __l2 = __len / 2;
42873e519524SHoward Hinnant        _ForwardIterator __m = __first;
4288ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
4289e4383379SHoward Hinnant        if (__comp(*__m, __value_))
42903e519524SHoward Hinnant        {
42913e519524SHoward Hinnant            __first = ++__m;
42923e519524SHoward Hinnant            __len -= __l2 + 1;
42933e519524SHoward Hinnant        }
4294e4383379SHoward Hinnant        else if (__comp(__value_, *__m))
42953e519524SHoward Hinnant        {
42963e519524SHoward Hinnant            __last = __m;
42973e519524SHoward Hinnant            __len = __l2;
42983e519524SHoward Hinnant        }
42993e519524SHoward Hinnant        else
43003e519524SHoward Hinnant        {
43013e519524SHoward Hinnant            _ForwardIterator __mp1 = __m;
43023e519524SHoward Hinnant            return pair<_ForwardIterator, _ForwardIterator>
43033e519524SHoward Hinnant                   (
4304e4383379SHoward Hinnant                      __lower_bound<_Compare>(__first, __m, __value_, __comp),
4305e4383379SHoward Hinnant                      __upper_bound<_Compare>(++__mp1, __last, __value_, __comp)
43063e519524SHoward Hinnant                   );
43073e519524SHoward Hinnant        }
43083e519524SHoward Hinnant    }
43093e519524SHoward Hinnant    return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
43103e519524SHoward Hinnant}
43113e519524SHoward Hinnant
43123e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
4313d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43143e519524SHoward Hinnantpair<_ForwardIterator, _ForwardIterator>
4315e4383379SHoward Hinnantequal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43163e519524SHoward Hinnant{
4317145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
43183e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
43193e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
4320e4383379SHoward Hinnant    return __equal_range<_Comp_ref>(__first, __last, __value_, __c);
4321145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
43223e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4323e4383379SHoward Hinnant    return __equal_range<_Comp_ref>(__first, __last, __value_, __comp);
4324145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
43253e519524SHoward Hinnant}
43263e519524SHoward Hinnant
43273e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
4328d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43293e519524SHoward Hinnantpair<_ForwardIterator, _ForwardIterator>
4330e4383379SHoward Hinnantequal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
43313e519524SHoward Hinnant{
4332e4383379SHoward Hinnant    return _VSTD::equal_range(__first, __last, __value_,
43333e519524SHoward Hinnant                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43343e519524SHoward Hinnant}
43353e519524SHoward Hinnant
43363e519524SHoward Hinnant// binary_search
43373e519524SHoward Hinnant
43383e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4339d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43403e519524SHoward Hinnantbool
4341e4383379SHoward Hinnant__binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43423e519524SHoward Hinnant{
4343e4383379SHoward Hinnant    __first = __lower_bound<_Compare>(__first, __last, __value_, __comp);
4344e4383379SHoward Hinnant    return __first != __last && !__comp(__value_, *__first);
43453e519524SHoward Hinnant}
43463e519524SHoward Hinnant
43473e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
4348d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43493e519524SHoward Hinnantbool
4350e4383379SHoward Hinnantbinary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43513e519524SHoward Hinnant{
4352145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
43533e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
43543e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
4355e4383379SHoward Hinnant    return __binary_search<_Comp_ref>(__first, __last, __value_, __c);
4356145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
43573e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4358e4383379SHoward Hinnant    return __binary_search<_Comp_ref>(__first, __last, __value_, __comp);
4359145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
43603e519524SHoward Hinnant}
43613e519524SHoward Hinnant
43623e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
4363d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43643e519524SHoward Hinnantbool
4365e4383379SHoward Hinnantbinary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
43663e519524SHoward Hinnant{
4367e4383379SHoward Hinnant    return _VSTD::binary_search(__first, __last, __value_,
43683e519524SHoward Hinnant                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43693e519524SHoward Hinnant}
43703e519524SHoward Hinnant
43713e519524SHoward Hinnant// merge
43723e519524SHoward Hinnant
43733e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
43743e519524SHoward Hinnant_OutputIterator
43753e519524SHoward Hinnant__merge(_InputIterator1 __first1, _InputIterator1 __last1,
43763e519524SHoward Hinnant        _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
43773e519524SHoward Hinnant{
43783e519524SHoward Hinnant    for (; __first1 != __last1; ++__result)
43793e519524SHoward Hinnant    {
43803e519524SHoward Hinnant        if (__first2 == __last2)
4381ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
43823e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
43833e519524SHoward Hinnant        {
43843e519524SHoward Hinnant            *__result = *__first2;
43853e519524SHoward Hinnant            ++__first2;
43863e519524SHoward Hinnant        }
43873e519524SHoward Hinnant        else
43883e519524SHoward Hinnant        {
43893e519524SHoward Hinnant            *__result = *__first1;
43903e519524SHoward Hinnant            ++__first1;
43913e519524SHoward Hinnant        }
43923e519524SHoward Hinnant    }
4393ce48a113SHoward Hinnant    return _VSTD::copy(__first2, __last2, __result);
43943e519524SHoward Hinnant}
43953e519524SHoward Hinnant
43963e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
43973e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
43983e519524SHoward Hinnant_OutputIterator
43993e519524SHoward Hinnantmerge(_InputIterator1 __first1, _InputIterator1 __last1,
44003e519524SHoward Hinnant      _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
44013e519524SHoward Hinnant{
4402145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
44033e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
44043e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
4405ce48a113SHoward Hinnant    return _VSTD::__merge<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __c);
4406145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
44073e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4408ce48a113SHoward Hinnant    return _VSTD::__merge<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
4409145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
44103e519524SHoward Hinnant}
44113e519524SHoward Hinnant
44123e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
44133e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
44143e519524SHoward Hinnant_OutputIterator
44153e519524SHoward Hinnantmerge(_InputIterator1 __first1, _InputIterator1 __last1,
44163e519524SHoward Hinnant      _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
44173e519524SHoward Hinnant{
44183e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
44193e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
44203e519524SHoward Hinnant    return merge(__first1, __last1, __first2, __last2, __result, __less<__v1, __v2>());
44213e519524SHoward Hinnant}
44223e519524SHoward Hinnant
44233e519524SHoward Hinnant// inplace_merge
44243e519524SHoward Hinnant
4425adfdae18SMarshall Clowtemplate <class _Compare, class _InputIterator1, class _InputIterator2,
4426adfdae18SMarshall Clow          class _OutputIterator>
4427adfdae18SMarshall Clowvoid __half_inplace_merge(_InputIterator1 __first1, _InputIterator1 __last1,
4428adfdae18SMarshall Clow                          _InputIterator2 __first2, _InputIterator2 __last2,
4429adfdae18SMarshall Clow                          _OutputIterator __result, _Compare __comp)
4430adfdae18SMarshall Clow{
4431adfdae18SMarshall Clow    for (; __first1 != __last1; ++__result)
4432adfdae18SMarshall Clow    {
4433adfdae18SMarshall Clow        if (__first2 == __last2)
4434adfdae18SMarshall Clow        {
4435adfdae18SMarshall Clow            _VSTD::move(__first1, __last1, __result);
4436adfdae18SMarshall Clow            return;
4437adfdae18SMarshall Clow        }
4438adfdae18SMarshall Clow
4439adfdae18SMarshall Clow        if (__comp(*__first2, *__first1))
4440adfdae18SMarshall Clow        {
4441adfdae18SMarshall Clow            *__result = _VSTD::move(*__first2);
4442adfdae18SMarshall Clow            ++__first2;
4443adfdae18SMarshall Clow        }
4444adfdae18SMarshall Clow        else
4445adfdae18SMarshall Clow        {
4446adfdae18SMarshall Clow            *__result = _VSTD::move(*__first1);
4447adfdae18SMarshall Clow            ++__first1;
4448adfdae18SMarshall Clow        }
4449adfdae18SMarshall Clow    }
4450adfdae18SMarshall Clow    // __first2 through __last2 are already in the right spot.
4451adfdae18SMarshall Clow}
4452adfdae18SMarshall Clow
44533e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
44543e519524SHoward Hinnantvoid
44553e519524SHoward Hinnant__buffered_inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
44563e519524SHoward Hinnant                _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
44573e519524SHoward Hinnant                                 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
44583e519524SHoward Hinnant                typename iterator_traits<_BidirectionalIterator>::value_type* __buff)
44593e519524SHoward Hinnant{
44603e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
44613e519524SHoward Hinnant    __destruct_n __d(0);
44623e519524SHoward Hinnant    unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
44633e519524SHoward Hinnant    if (__len1 <= __len2)
44643e519524SHoward Hinnant    {
44653e519524SHoward Hinnant        value_type* __p = __buff;
4466910285b2SEric Fiselier        for (_BidirectionalIterator __i = __first; __i != __middle; __d.__incr((value_type*)0), (void) ++__i, ++__p)
4467ce48a113SHoward Hinnant            ::new(__p) value_type(_VSTD::move(*__i));
4468adfdae18SMarshall Clow        __half_inplace_merge(__buff, __p, __middle, __last, __first, __comp);
44693e519524SHoward Hinnant    }
44703e519524SHoward Hinnant    else
44713e519524SHoward Hinnant    {
44723e519524SHoward Hinnant        value_type* __p = __buff;
4473910285b2SEric Fiselier        for (_BidirectionalIterator __i = __middle; __i != __last; __d.__incr((value_type*)0), (void) ++__i, ++__p)
4474ce48a113SHoward Hinnant            ::new(__p) value_type(_VSTD::move(*__i));
44753e519524SHoward Hinnant        typedef reverse_iterator<_BidirectionalIterator> _RBi;
44763e519524SHoward Hinnant        typedef reverse_iterator<value_type*> _Rv;
4477adfdae18SMarshall Clow        __half_inplace_merge(_Rv(__p), _Rv(__buff),
4478adfdae18SMarshall Clow                             _RBi(__middle), _RBi(__first),
4479a763b36fSMarshall Clow                             _RBi(__last), __invert<_Compare>(__comp));
44803e519524SHoward Hinnant    }
44813e519524SHoward Hinnant}
44823e519524SHoward Hinnant
44833e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
44843e519524SHoward Hinnantvoid
44853e519524SHoward Hinnant__inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
44863e519524SHoward Hinnant                _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
44873e519524SHoward Hinnant                                 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
44883e519524SHoward Hinnant                typename iterator_traits<_BidirectionalIterator>::value_type* __buff, ptrdiff_t __buff_size)
44893e519524SHoward Hinnant{
44903e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
44913e519524SHoward Hinnant    while (true)
44923e519524SHoward Hinnant    {
44933e519524SHoward Hinnant        // if __middle == __last, we're done
44943e519524SHoward Hinnant        if (__len2 == 0)
44953e519524SHoward Hinnant            return;
4496526e0929SMarshall Clow        if (__len1 <= __buff_size || __len2 <= __buff_size)
4497526e0929SMarshall Clow            return __buffered_inplace_merge<_Compare>
4498526e0929SMarshall Clow                   (__first, __middle, __last, __comp, __len1, __len2, __buff);
44993e519524SHoward Hinnant        // shrink [__first, __middle) as much as possible (with no moves), returning if it shrinks to 0
4500910285b2SEric Fiselier        for (; true; ++__first, (void) --__len1)
45013e519524SHoward Hinnant        {
45023e519524SHoward Hinnant            if (__len1 == 0)
45033e519524SHoward Hinnant                return;
45043e519524SHoward Hinnant            if (__comp(*__middle, *__first))
45053e519524SHoward Hinnant                break;
45063e519524SHoward Hinnant        }
45073e519524SHoward Hinnant        // __first < __middle < __last
45083e519524SHoward Hinnant        // *__first > *__middle
45093e519524SHoward Hinnant        // partition [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last) such that
45103e519524SHoward Hinnant        //     all elements in:
45113e519524SHoward Hinnant        //         [__first, __m1)  <= [__middle, __m2)
45123e519524SHoward Hinnant        //         [__middle, __m2) <  [__m1, __middle)
45133e519524SHoward Hinnant        //         [__m1, __middle) <= [__m2, __last)
45143e519524SHoward Hinnant        //     and __m1 or __m2 is in the middle of its range
45153e519524SHoward Hinnant        _BidirectionalIterator __m1;  // "median" of [__first, __middle)
45163e519524SHoward Hinnant        _BidirectionalIterator __m2;  // "median" of [__middle, __last)
45173e519524SHoward Hinnant        difference_type __len11;      // distance(__first, __m1)
45183e519524SHoward Hinnant        difference_type __len21;      // distance(__middle, __m2)
45193e519524SHoward Hinnant        // binary search smaller range
45203e519524SHoward Hinnant        if (__len1 < __len2)
45213e519524SHoward Hinnant        {   // __len >= 1, __len2 >= 2
45223e519524SHoward Hinnant            __len21 = __len2 / 2;
45233e519524SHoward Hinnant            __m2 = __middle;
4524ce48a113SHoward Hinnant            _VSTD::advance(__m2, __len21);
45253e519524SHoward Hinnant            __m1 = __upper_bound<_Compare>(__first, __middle, *__m2, __comp);
4526ce48a113SHoward Hinnant            __len11 = _VSTD::distance(__first, __m1);
45273e519524SHoward Hinnant        }
45283e519524SHoward Hinnant        else
45293e519524SHoward Hinnant        {
45303e519524SHoward Hinnant            if (__len1 == 1)
45313e519524SHoward Hinnant            {   // __len1 >= __len2 && __len2 > 0, therefore __len2 == 1
45323e519524SHoward Hinnant                // It is known *__first > *__middle
45333e519524SHoward Hinnant                swap(*__first, *__middle);
45343e519524SHoward Hinnant                return;
45353e519524SHoward Hinnant            }
45363e519524SHoward Hinnant            // __len1 >= 2, __len2 >= 1
45373e519524SHoward Hinnant            __len11 = __len1 / 2;
45383e519524SHoward Hinnant            __m1 = __first;
4539ce48a113SHoward Hinnant            _VSTD::advance(__m1, __len11);
45403e519524SHoward Hinnant            __m2 = __lower_bound<_Compare>(__middle, __last, *__m1, __comp);
4541ce48a113SHoward Hinnant            __len21 = _VSTD::distance(__middle, __m2);
45423e519524SHoward Hinnant        }
45433e519524SHoward Hinnant        difference_type __len12 = __len1 - __len11;  // distance(__m1, __middle)
45443e519524SHoward Hinnant        difference_type __len22 = __len2 - __len21;  // distance(__m2, __last)
45453e519524SHoward Hinnant        // [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last)
45463e519524SHoward Hinnant        // swap middle two partitions
4547ce48a113SHoward Hinnant        __middle = _VSTD::rotate(__m1, __middle, __m2);
45483e519524SHoward Hinnant        // __len12 and __len21 now have swapped meanings
45493e519524SHoward Hinnant        // merge smaller range with recurisve call and larger with tail recursion elimination
45503e519524SHoward Hinnant        if (__len11 + __len21 < __len12 + __len22)
45513e519524SHoward Hinnant        {
45523e519524SHoward Hinnant            __inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
45533e519524SHoward Hinnant//          __inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
45543e519524SHoward Hinnant            __first = __middle;
45553e519524SHoward Hinnant            __middle = __m2;
45563e519524SHoward Hinnant            __len1 = __len12;
45573e519524SHoward Hinnant            __len2 = __len22;
45583e519524SHoward Hinnant        }
45593e519524SHoward Hinnant        else
45603e519524SHoward Hinnant        {
45613e519524SHoward Hinnant            __inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
45623e519524SHoward Hinnant//          __inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
45633e519524SHoward Hinnant            __last = __middle;
45643e519524SHoward Hinnant            __middle = __m1;
45653e519524SHoward Hinnant            __len1 = __len11;
45663e519524SHoward Hinnant            __len2 = __len21;
45673e519524SHoward Hinnant        }
45683e519524SHoward Hinnant    }
45693e519524SHoward Hinnant}
45703e519524SHoward Hinnant
45713e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _Compare>
45723e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
45733e519524SHoward Hinnantvoid
45743e519524SHoward Hinnantinplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
45753e519524SHoward Hinnant              _Compare __comp)
45763e519524SHoward Hinnant{
45773e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
45783e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
4579ce48a113SHoward Hinnant    difference_type __len1 = _VSTD::distance(__first, __middle);
4580ce48a113SHoward Hinnant    difference_type __len2 = _VSTD::distance(__middle, __last);
4581ce48a113SHoward Hinnant    difference_type __buf_size = _VSTD::min(__len1, __len2);
45820b48cf9aSMarshall Clow    pair<value_type*, ptrdiff_t> __buf = _VSTD::get_temporary_buffer<value_type>(__buf_size);
45830b48cf9aSMarshall Clow    unique_ptr<value_type, __return_temporary_buffer> __h(__buf.first);
45840b48cf9aSMarshall Clow
4585145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
45863e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
45873e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
4588ce48a113SHoward Hinnant    return _VSTD::__inplace_merge<_Comp_ref>(__first, __middle, __last, __c, __len1, __len2,
45893e519524SHoward Hinnant                                            __buf.first, __buf.second);
4590145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
45913e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4592ce48a113SHoward Hinnant    return _VSTD::__inplace_merge<_Comp_ref>(__first, __middle, __last, __comp, __len1, __len2,
45933e519524SHoward Hinnant                                            __buf.first, __buf.second);
4594145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
45953e519524SHoward Hinnant}
45963e519524SHoward Hinnant
45973e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
45983e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
45993e519524SHoward Hinnantvoid
46003e519524SHoward Hinnantinplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last)
46013e519524SHoward Hinnant{
4602ce48a113SHoward Hinnant    _VSTD::inplace_merge(__first, __middle, __last,
46033e519524SHoward Hinnant                        __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
46043e519524SHoward Hinnant}
46053e519524SHoward Hinnant
46063e519524SHoward Hinnant// stable_sort
46073e519524SHoward Hinnant
46083e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2>
46093e519524SHoward Hinnantvoid
46103e519524SHoward Hinnant__merge_move_construct(_InputIterator1 __first1, _InputIterator1 __last1,
46113e519524SHoward Hinnant        _InputIterator2 __first2, _InputIterator2 __last2,
46123e519524SHoward Hinnant        typename iterator_traits<_InputIterator1>::value_type* __result, _Compare __comp)
46133e519524SHoward Hinnant{
46143e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type value_type;
46153e519524SHoward Hinnant    __destruct_n __d(0);
46163e519524SHoward Hinnant    unique_ptr<value_type, __destruct_n&> __h(__result, __d);
46173e519524SHoward Hinnant    for (; true; ++__result)
46183e519524SHoward Hinnant    {
46193e519524SHoward Hinnant        if (__first1 == __last1)
46203e519524SHoward Hinnant        {
46213e519524SHoward Hinnant            for (; __first2 != __last2; ++__first2, ++__result, __d.__incr((value_type*)0))
4622ce48a113SHoward Hinnant                ::new (__result) value_type(_VSTD::move(*__first2));
46233e519524SHoward Hinnant            __h.release();
46243e519524SHoward Hinnant            return;
46253e519524SHoward Hinnant        }
46263e519524SHoward Hinnant        if (__first2 == __last2)
46273e519524SHoward Hinnant        {
46283e519524SHoward Hinnant            for (; __first1 != __last1; ++__first1, ++__result, __d.__incr((value_type*)0))
4629ce48a113SHoward Hinnant                ::new (__result) value_type(_VSTD::move(*__first1));
46303e519524SHoward Hinnant            __h.release();
46313e519524SHoward Hinnant            return;
46323e519524SHoward Hinnant        }
46333e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
46343e519524SHoward Hinnant        {
4635ce48a113SHoward Hinnant            ::new (__result) value_type(_VSTD::move(*__first2));
46363e519524SHoward Hinnant            __d.__incr((value_type*)0);
46373e519524SHoward Hinnant            ++__first2;
46383e519524SHoward Hinnant        }
46393e519524SHoward Hinnant        else
46403e519524SHoward Hinnant        {
4641ce48a113SHoward Hinnant            ::new (__result) value_type(_VSTD::move(*__first1));
46423e519524SHoward Hinnant            __d.__incr((value_type*)0);
46433e519524SHoward Hinnant            ++__first1;
46443e519524SHoward Hinnant        }
46453e519524SHoward Hinnant    }
46463e519524SHoward Hinnant}
46473e519524SHoward Hinnant
46483e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
46493e519524SHoward Hinnantvoid
46503e519524SHoward Hinnant__merge_move_assign(_InputIterator1 __first1, _InputIterator1 __last1,
46513e519524SHoward Hinnant        _InputIterator2 __first2, _InputIterator2 __last2,
46523e519524SHoward Hinnant        _OutputIterator __result, _Compare __comp)
46533e519524SHoward Hinnant{
46543e519524SHoward Hinnant    for (; __first1 != __last1; ++__result)
46553e519524SHoward Hinnant    {
46563e519524SHoward Hinnant        if (__first2 == __last2)
46573e519524SHoward Hinnant        {
46583e519524SHoward Hinnant            for (; __first1 != __last1; ++__first1, ++__result)
4659ce48a113SHoward Hinnant                *__result = _VSTD::move(*__first1);
46603e519524SHoward Hinnant            return;
46613e519524SHoward Hinnant        }
46623e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
46633e519524SHoward Hinnant        {
4664ce48a113SHoward Hinnant            *__result = _VSTD::move(*__first2);
46653e519524SHoward Hinnant            ++__first2;
46663e519524SHoward Hinnant        }
46673e519524SHoward Hinnant        else
46683e519524SHoward Hinnant        {
4669ce48a113SHoward Hinnant            *__result = _VSTD::move(*__first1);
46703e519524SHoward Hinnant            ++__first1;
46713e519524SHoward Hinnant        }
46723e519524SHoward Hinnant    }
46733e519524SHoward Hinnant    for (; __first2 != __last2; ++__first2, ++__result)
4674ce48a113SHoward Hinnant        *__result = _VSTD::move(*__first2);
46753e519524SHoward Hinnant}
46763e519524SHoward Hinnant
46773e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
46783e519524SHoward Hinnantvoid
46793e519524SHoward Hinnant__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
46803e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46813e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size);
46823e519524SHoward Hinnant
46833e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
46843e519524SHoward Hinnantvoid
46853e519524SHoward Hinnant__stable_sort_move(_RandomAccessIterator __first1, _RandomAccessIterator __last1, _Compare __comp,
46863e519524SHoward Hinnant                   typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46873e519524SHoward Hinnant                   typename iterator_traits<_RandomAccessIterator>::value_type* __first2)
46883e519524SHoward Hinnant{
46893e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
46903e519524SHoward Hinnant    switch (__len)
46913e519524SHoward Hinnant    {
46923e519524SHoward Hinnant    case 0:
46933e519524SHoward Hinnant        return;
46943e519524SHoward Hinnant    case 1:
4695ce48a113SHoward Hinnant        ::new(__first2) value_type(_VSTD::move(*__first1));
46963e519524SHoward Hinnant        return;
46973e519524SHoward Hinnant    case 2:
46983e519524SHoward Hinnant       __destruct_n __d(0);
46993e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h2(__first2, __d);
47003e519524SHoward Hinnant         if (__comp(*--__last1, *__first1))
47013e519524SHoward Hinnant        {
4702ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__last1));
47033e519524SHoward Hinnant            __d.__incr((value_type*)0);
47043e519524SHoward Hinnant            ++__first2;
4705ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__first1));
47063e519524SHoward Hinnant        }
47073e519524SHoward Hinnant        else
47083e519524SHoward Hinnant        {
4709ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__first1));
47103e519524SHoward Hinnant            __d.__incr((value_type*)0);
47113e519524SHoward Hinnant            ++__first2;
4712ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__last1));
47133e519524SHoward Hinnant        }
47143e519524SHoward Hinnant        __h2.release();
47153e519524SHoward Hinnant        return;
47163e519524SHoward Hinnant    }
47173e519524SHoward Hinnant    if (__len <= 8)
47183e519524SHoward Hinnant    {
47193e519524SHoward Hinnant        __insertion_sort_move<_Compare>(__first1, __last1, __first2, __comp);
47203e519524SHoward Hinnant        return;
47213e519524SHoward Hinnant    }
47223e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
47233e519524SHoward Hinnant    _RandomAccessIterator __m = __first1 + __l2;
47243e519524SHoward Hinnant    __stable_sort<_Compare>(__first1, __m, __comp, __l2, __first2, __l2);
47253e519524SHoward Hinnant    __stable_sort<_Compare>(__m, __last1, __comp, __len - __l2, __first2 + __l2, __len - __l2);
47263e519524SHoward Hinnant    __merge_move_construct<_Compare>(__first1, __m, __m, __last1, __first2, __comp);
47273e519524SHoward Hinnant}
47283e519524SHoward Hinnant
47293e519524SHoward Hinnanttemplate <class _Tp>
47303e519524SHoward Hinnantstruct __stable_sort_switch
47313e519524SHoward Hinnant{
4732ca740483SHoward Hinnant    static const unsigned value = 128*is_trivially_copy_assignable<_Tp>::value;
47333e519524SHoward Hinnant};
47343e519524SHoward Hinnant
47353e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
47363e519524SHoward Hinnantvoid
47373e519524SHoward Hinnant__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
47383e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::difference_type __len,
47393e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size)
47403e519524SHoward Hinnant{
47413e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
47423e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47433e519524SHoward Hinnant    switch (__len)
47443e519524SHoward Hinnant    {
47453e519524SHoward Hinnant    case 0:
47463e519524SHoward Hinnant    case 1:
47473e519524SHoward Hinnant        return;
47483e519524SHoward Hinnant    case 2:
47493e519524SHoward Hinnant        if (__comp(*--__last, *__first))
47503e519524SHoward Hinnant            swap(*__first, *__last);
47513e519524SHoward Hinnant        return;
47523e519524SHoward Hinnant    }
47533e519524SHoward Hinnant    if (__len <= static_cast<difference_type>(__stable_sort_switch<value_type>::value))
47543e519524SHoward Hinnant    {
47553e519524SHoward Hinnant        __insertion_sort<_Compare>(__first, __last, __comp);
47563e519524SHoward Hinnant        return;
47573e519524SHoward Hinnant    }
47583e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
47593e519524SHoward Hinnant    _RandomAccessIterator __m = __first + __l2;
47603e519524SHoward Hinnant    if (__len <= __buff_size)
47613e519524SHoward Hinnant    {
47623e519524SHoward Hinnant        __destruct_n __d(0);
47633e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
47643e519524SHoward Hinnant        __stable_sort_move<_Compare>(__first, __m, __comp, __l2, __buff);
47653e519524SHoward Hinnant        __d.__set(__l2, (value_type*)0);
47663e519524SHoward Hinnant        __stable_sort_move<_Compare>(__m, __last, __comp, __len - __l2, __buff + __l2);
47673e519524SHoward Hinnant        __d.__set(__len, (value_type*)0);
47683e519524SHoward Hinnant        __merge_move_assign<_Compare>(__buff, __buff + __l2, __buff + __l2, __buff + __len, __first, __comp);
47693e519524SHoward Hinnant//         __merge<_Compare>(move_iterator<value_type*>(__buff),
47703e519524SHoward Hinnant//                           move_iterator<value_type*>(__buff + __l2),
47713e519524SHoward Hinnant//                           move_iterator<_RandomAccessIterator>(__buff + __l2),
47723e519524SHoward Hinnant//                           move_iterator<_RandomAccessIterator>(__buff + __len),
47733e519524SHoward Hinnant//                           __first, __comp);
47743e519524SHoward Hinnant        return;
47753e519524SHoward Hinnant    }
47763e519524SHoward Hinnant    __stable_sort<_Compare>(__first, __m, __comp, __l2, __buff, __buff_size);
47773e519524SHoward Hinnant    __stable_sort<_Compare>(__m, __last, __comp, __len - __l2, __buff, __buff_size);
47783e519524SHoward Hinnant    __inplace_merge<_Compare>(__first, __m, __last, __comp, __l2, __len - __l2, __buff, __buff_size);
47793e519524SHoward Hinnant}
47803e519524SHoward Hinnant
47813e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
47823e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
47833e519524SHoward Hinnantvoid
47843e519524SHoward Hinnantstable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
47853e519524SHoward Hinnant{
47863e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
47873e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47883e519524SHoward Hinnant    difference_type __len = __last - __first;
47893e519524SHoward Hinnant    pair<value_type*, ptrdiff_t> __buf(0, 0);
47903e519524SHoward Hinnant    unique_ptr<value_type, __return_temporary_buffer> __h;
47913e519524SHoward Hinnant    if (__len > static_cast<difference_type>(__stable_sort_switch<value_type>::value))
47923e519524SHoward Hinnant    {
4793ce48a113SHoward Hinnant        __buf = _VSTD::get_temporary_buffer<value_type>(__len);
47943e519524SHoward Hinnant        __h.reset(__buf.first);
47953e519524SHoward Hinnant    }
4796145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
47973e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
47983e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
47993e519524SHoward Hinnant    __stable_sort<_Comp_ref>(__first, __last, __c, __len, __buf.first, __buf.second);
4800145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
48013e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
48023e519524SHoward Hinnant    __stable_sort<_Comp_ref>(__first, __last, __comp, __len, __buf.first, __buf.second);
4803145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
48043e519524SHoward Hinnant}
48053e519524SHoward Hinnant
48063e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
48073e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
48083e519524SHoward Hinnantvoid
48093e519524SHoward Hinnantstable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
48103e519524SHoward Hinnant{
4811ce48a113SHoward Hinnant    _VSTD::stable_sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48123e519524SHoward Hinnant}
48133e519524SHoward Hinnant
48143e519524SHoward Hinnant// is_heap_until
48153e519524SHoward Hinnant
48163e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
481749c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
48183e519524SHoward Hinnantis_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
48193e519524SHoward Hinnant{
4820ce48a113SHoward Hinnant    typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
48213e519524SHoward Hinnant    difference_type __len = __last - __first;
48223e519524SHoward Hinnant    difference_type __p = 0;
48233e519524SHoward Hinnant    difference_type __c = 1;
48243e519524SHoward Hinnant    _RandomAccessIterator __pp = __first;
48253e519524SHoward Hinnant    while (__c < __len)
48263e519524SHoward Hinnant    {
48273e519524SHoward Hinnant        _RandomAccessIterator __cp = __first + __c;
48283e519524SHoward Hinnant        if (__comp(*__pp, *__cp))
48293e519524SHoward Hinnant            return __cp;
48303e519524SHoward Hinnant        ++__c;
48313e519524SHoward Hinnant        ++__cp;
48323e519524SHoward Hinnant        if (__c == __len)
48333e519524SHoward Hinnant            return __last;
48343e519524SHoward Hinnant        if (__comp(*__pp, *__cp))
48353e519524SHoward Hinnant            return __cp;
48363e519524SHoward Hinnant        ++__p;
48373e519524SHoward Hinnant        ++__pp;
48383e519524SHoward Hinnant        __c = 2 * __p + 1;
48393e519524SHoward Hinnant    }
48403e519524SHoward Hinnant    return __last;
48413e519524SHoward Hinnant}
48423e519524SHoward Hinnant
48433e519524SHoward Hinnanttemplate<class _RandomAccessIterator>
484449c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48453e519524SHoward Hinnant_RandomAccessIterator
48463e519524SHoward Hinnantis_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
48473e519524SHoward Hinnant{
4848ce48a113SHoward Hinnant    return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48493e519524SHoward Hinnant}
48503e519524SHoward Hinnant
48513e519524SHoward Hinnant// is_heap
48523e519524SHoward Hinnant
48533e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
485449c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48553e519524SHoward Hinnantbool
48563e519524SHoward Hinnantis_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
48573e519524SHoward Hinnant{
4858ce48a113SHoward Hinnant    return _VSTD::is_heap_until(__first, __last, __comp) == __last;
48593e519524SHoward Hinnant}
48603e519524SHoward Hinnant
48613e519524SHoward Hinnanttemplate<class _RandomAccessIterator>
486249c7643cSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48633e519524SHoward Hinnantbool
48643e519524SHoward Hinnantis_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
48653e519524SHoward Hinnant{
4866ce48a113SHoward Hinnant    return _VSTD::is_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48673e519524SHoward Hinnant}
48683e519524SHoward Hinnant
48693e519524SHoward Hinnant// push_heap
48703e519524SHoward Hinnant
48713e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
48723e519524SHoward Hinnantvoid
48738b512602SDavid Majnemer__sift_up(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
48743e519524SHoward Hinnant          typename iterator_traits<_RandomAccessIterator>::difference_type __len)
48753e519524SHoward Hinnant{
48763e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
48773e519524SHoward Hinnant    if (__len > 1)
48783e519524SHoward Hinnant    {
48793e519524SHoward Hinnant        __len = (__len - 2) / 2;
48803e519524SHoward Hinnant        _RandomAccessIterator __ptr = __first + __len;
48813e519524SHoward Hinnant        if (__comp(*__ptr, *--__last))
48823e519524SHoward Hinnant        {
4883ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__last));
48843e519524SHoward Hinnant            do
48853e519524SHoward Hinnant            {
4886ce48a113SHoward Hinnant                *__last = _VSTD::move(*__ptr);
48873e519524SHoward Hinnant                __last = __ptr;
48883e519524SHoward Hinnant                if (__len == 0)
48893e519524SHoward Hinnant                    break;
48903e519524SHoward Hinnant                __len = (__len - 1) / 2;
48913e519524SHoward Hinnant                __ptr = __first + __len;
48923e519524SHoward Hinnant            } while (__comp(*__ptr, __t));
4893ce48a113SHoward Hinnant            *__last = _VSTD::move(__t);
48943e519524SHoward Hinnant        }
48953e519524SHoward Hinnant    }
48963e519524SHoward Hinnant}
48973e519524SHoward Hinnant
48983e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
48993e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49003e519524SHoward Hinnantvoid
49013e519524SHoward Hinnantpush_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49023e519524SHoward Hinnant{
4903145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
49043e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
49053e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
49068b512602SDavid Majnemer    __sift_up<_Comp_ref>(__first, __last, __c, __last - __first);
4907145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
49083e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
49098b512602SDavid Majnemer    __sift_up<_Comp_ref>(__first, __last, __comp, __last - __first);
4910145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
49113e519524SHoward Hinnant}
49123e519524SHoward Hinnant
49133e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
49143e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49153e519524SHoward Hinnantvoid
49163e519524SHoward Hinnantpush_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
49173e519524SHoward Hinnant{
4918ce48a113SHoward Hinnant    _VSTD::push_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
49193e519524SHoward Hinnant}
49203e519524SHoward Hinnant
49213e519524SHoward Hinnant// pop_heap
49223e519524SHoward Hinnant
49233e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
49248b512602SDavid Majnemervoid
4925fd838227SEric Fiselier__sift_down(_RandomAccessIterator __first, _RandomAccessIterator /*__last*/,
4926fd838227SEric Fiselier            _Compare __comp,
49278b512602SDavid Majnemer            typename iterator_traits<_RandomAccessIterator>::difference_type __len,
49288b512602SDavid Majnemer            _RandomAccessIterator __start)
49298b512602SDavid Majnemer{
49308b512602SDavid Majnemer    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
49318b512602SDavid Majnemer    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
49328b512602SDavid Majnemer    // left-child of __start is at 2 * __start + 1
49338b512602SDavid Majnemer    // right-child of __start is at 2 * __start + 2
49348b512602SDavid Majnemer    difference_type __child = __start - __first;
49358b512602SDavid Majnemer
49368b512602SDavid Majnemer    if (__len < 2 || (__len - 2) / 2 < __child)
49378b512602SDavid Majnemer        return;
49388b512602SDavid Majnemer
49398b512602SDavid Majnemer    __child = 2 * __child + 1;
49408b512602SDavid Majnemer    _RandomAccessIterator __child_i = __first + __child;
49418b512602SDavid Majnemer
49428b512602SDavid Majnemer    if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
49438b512602SDavid Majnemer        // right-child exists and is greater than left-child
49448b512602SDavid Majnemer        ++__child_i;
49458b512602SDavid Majnemer        ++__child;
49468b512602SDavid Majnemer    }
49478b512602SDavid Majnemer
49488b512602SDavid Majnemer    // check if we are in heap-order
49498b512602SDavid Majnemer    if (__comp(*__child_i, *__start))
49508b512602SDavid Majnemer        // we are, __start is larger than it's largest child
49518b512602SDavid Majnemer        return;
49528b512602SDavid Majnemer
49538b512602SDavid Majnemer    value_type __top(_VSTD::move(*__start));
49548b512602SDavid Majnemer    do
49558b512602SDavid Majnemer    {
49568b512602SDavid Majnemer        // we are not in heap-order, swap the parent with it's largest child
49578b512602SDavid Majnemer        *__start = _VSTD::move(*__child_i);
49588b512602SDavid Majnemer        __start = __child_i;
49598b512602SDavid Majnemer
49608b512602SDavid Majnemer        if ((__len - 2) / 2 < __child)
49618b512602SDavid Majnemer            break;
49628b512602SDavid Majnemer
49638b512602SDavid Majnemer        // recompute the child based off of the updated parent
49648b512602SDavid Majnemer        __child = 2 * __child + 1;
49658b512602SDavid Majnemer        __child_i = __first + __child;
49668b512602SDavid Majnemer
49678b512602SDavid Majnemer        if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
49688b512602SDavid Majnemer            // right-child exists and is greater than left-child
49698b512602SDavid Majnemer            ++__child_i;
49708b512602SDavid Majnemer            ++__child;
49718b512602SDavid Majnemer        }
49728b512602SDavid Majnemer
49738b512602SDavid Majnemer        // check if we are in heap-order
49748b512602SDavid Majnemer    } while (!__comp(*__child_i, __top));
49758b512602SDavid Majnemer    *__start = _VSTD::move(__top);
49768b512602SDavid Majnemer}
49778b512602SDavid Majnemer
49788b512602SDavid Majnemertemplate <class _Compare, class _RandomAccessIterator>
49793e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49803e519524SHoward Hinnantvoid
49813e519524SHoward Hinnant__pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
49823e519524SHoward Hinnant           typename iterator_traits<_RandomAccessIterator>::difference_type __len)
49833e519524SHoward Hinnant{
49843e519524SHoward Hinnant    if (__len > 1)
49853e519524SHoward Hinnant    {
49863e519524SHoward Hinnant        swap(*__first, *--__last);
49878b512602SDavid Majnemer        __sift_down<_Compare>(__first, __last, __comp, __len - 1, __first);
49883e519524SHoward Hinnant    }
49893e519524SHoward Hinnant}
49903e519524SHoward Hinnant
49913e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
49923e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49933e519524SHoward Hinnantvoid
49943e519524SHoward Hinnantpop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49953e519524SHoward Hinnant{
4996145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
49973e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
49983e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
49993e519524SHoward Hinnant    __pop_heap<_Comp_ref>(__first, __last, __c, __last - __first);
5000145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
50013e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
50023e519524SHoward Hinnant    __pop_heap<_Comp_ref>(__first, __last, __comp, __last - __first);
5003145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
50043e519524SHoward Hinnant}
50053e519524SHoward Hinnant
50063e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
50073e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50083e519524SHoward Hinnantvoid
50093e519524SHoward Hinnantpop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
50103e519524SHoward Hinnant{
5011ce48a113SHoward Hinnant    _VSTD::pop_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50123e519524SHoward Hinnant}
50133e519524SHoward Hinnant
50143e519524SHoward Hinnant// make_heap
50153e519524SHoward Hinnant
50163e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
50173e519524SHoward Hinnantvoid
50183e519524SHoward Hinnant__make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
50193e519524SHoward Hinnant{
50203e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
50213e519524SHoward Hinnant    difference_type __n = __last - __first;
50223e519524SHoward Hinnant    if (__n > 1)
50233e519524SHoward Hinnant    {
50248b512602SDavid Majnemer        // start from the first parent, there is no need to consider children
50258b512602SDavid Majnemer        for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start)
50268b512602SDavid Majnemer        {
50278b512602SDavid Majnemer            __sift_down<_Compare>(__first, __last, __comp, __n, __first + __start);
50288b512602SDavid Majnemer        }
50293e519524SHoward Hinnant    }
50303e519524SHoward Hinnant}
50313e519524SHoward Hinnant
50323e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
50333e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50343e519524SHoward Hinnantvoid
50353e519524SHoward Hinnantmake_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
50363e519524SHoward Hinnant{
5037145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
50383e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
50393e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
50403e519524SHoward Hinnant    __make_heap<_Comp_ref>(__first, __last, __c);
5041145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
50423e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
50433e519524SHoward Hinnant    __make_heap<_Comp_ref>(__first, __last, __comp);
5044145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
50453e519524SHoward Hinnant}
50463e519524SHoward Hinnant
50473e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
50483e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50493e519524SHoward Hinnantvoid
50503e519524SHoward Hinnantmake_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
50513e519524SHoward Hinnant{
5052ce48a113SHoward Hinnant    _VSTD::make_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50533e519524SHoward Hinnant}
50543e519524SHoward Hinnant
50553e519524SHoward Hinnant// sort_heap
50563e519524SHoward Hinnant
50573e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
50583e519524SHoward Hinnantvoid
50593e519524SHoward Hinnant__sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
50603e519524SHoward Hinnant{
50613e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
50623e519524SHoward Hinnant    for (difference_type __n = __last - __first; __n > 1; --__last, --__n)
50633e519524SHoward Hinnant        __pop_heap<_Compare>(__first, __last, __comp, __n);
50643e519524SHoward Hinnant}
50653e519524SHoward Hinnant
50663e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
50673e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50683e519524SHoward Hinnantvoid
50693e519524SHoward Hinnantsort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
50703e519524SHoward Hinnant{
5071145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
50723e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
50733e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
50743e519524SHoward Hinnant    __sort_heap<_Comp_ref>(__first, __last, __c);
5075145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
50763e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
50773e519524SHoward Hinnant    __sort_heap<_Comp_ref>(__first, __last, __comp);
5078145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
50793e519524SHoward Hinnant}
50803e519524SHoward Hinnant
50813e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
50823e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50833e519524SHoward Hinnantvoid
50843e519524SHoward Hinnantsort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
50853e519524SHoward Hinnant{
5086ce48a113SHoward Hinnant    _VSTD::sort_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50873e519524SHoward Hinnant}
50883e519524SHoward Hinnant
50893e519524SHoward Hinnant// partial_sort
50903e519524SHoward Hinnant
50913e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
50923e519524SHoward Hinnantvoid
50933e519524SHoward Hinnant__partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
50943e519524SHoward Hinnant             _Compare __comp)
50953e519524SHoward Hinnant{
50963e519524SHoward Hinnant    __make_heap<_Compare>(__first, __middle, __comp);
50973e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator>::difference_type __len = __middle - __first;
50983e519524SHoward Hinnant    for (_RandomAccessIterator __i = __middle; __i != __last; ++__i)
50993e519524SHoward Hinnant    {
51003e519524SHoward Hinnant        if (__comp(*__i, *__first))
51013e519524SHoward Hinnant        {
51023e519524SHoward Hinnant            swap(*__i, *__first);
51038b512602SDavid Majnemer            __sift_down<_Compare>(__first, __middle, __comp, __len, __first);
51043e519524SHoward Hinnant        }
51053e519524SHoward Hinnant    }
51063e519524SHoward Hinnant    __sort_heap<_Compare>(__first, __middle, __comp);
51073e519524SHoward Hinnant}
51083e519524SHoward Hinnant
51093e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
51103e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
51113e519524SHoward Hinnantvoid
51123e519524SHoward Hinnantpartial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
51133e519524SHoward Hinnant             _Compare __comp)
51143e519524SHoward Hinnant{
5115145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
51163e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
51173e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
51183e519524SHoward Hinnant    __partial_sort<_Comp_ref>(__first, __middle, __last, __c);
5119145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
51203e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
51213e519524SHoward Hinnant    __partial_sort<_Comp_ref>(__first, __middle, __last, __comp);
5122145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
51233e519524SHoward Hinnant}
51243e519524SHoward Hinnant
51253e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
51263e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
51273e519524SHoward Hinnantvoid
51283e519524SHoward Hinnantpartial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
51293e519524SHoward Hinnant{
5130ce48a113SHoward Hinnant    _VSTD::partial_sort(__first, __middle, __last,
51313e519524SHoward Hinnant                       __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
51323e519524SHoward Hinnant}
51333e519524SHoward Hinnant
51343e519524SHoward Hinnant// partial_sort_copy
51353e519524SHoward Hinnant
51363e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator, class _RandomAccessIterator>
51373e519524SHoward Hinnant_RandomAccessIterator
51383e519524SHoward Hinnant__partial_sort_copy(_InputIterator __first, _InputIterator __last,
51393e519524SHoward Hinnant                    _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
51403e519524SHoward Hinnant{
51413e519524SHoward Hinnant    _RandomAccessIterator __r = __result_first;
51423e519524SHoward Hinnant    if (__r != __result_last)
51433e519524SHoward Hinnant    {
5144910285b2SEric Fiselier        for (; __first != __last && __r != __result_last; (void) ++__first, ++__r)
51453e519524SHoward Hinnant            *__r = *__first;
51463e519524SHoward Hinnant        __make_heap<_Compare>(__result_first, __r, __comp);
51478b512602SDavid Majnemer        typename iterator_traits<_RandomAccessIterator>::difference_type __len = __r - __result_first;
51483e519524SHoward Hinnant        for (; __first != __last; ++__first)
51493e519524SHoward Hinnant            if (__comp(*__first, *__result_first))
51503e519524SHoward Hinnant            {
51513e519524SHoward Hinnant                *__result_first = *__first;
51528b512602SDavid Majnemer                __sift_down<_Compare>(__result_first, __r, __comp, __len, __result_first);
51533e519524SHoward Hinnant            }
51543e519524SHoward Hinnant        __sort_heap<_Compare>(__result_first, __r, __comp);
51553e519524SHoward Hinnant    }
51563e519524SHoward Hinnant    return __r;
51573e519524SHoward Hinnant}
51583e519524SHoward Hinnant
51593e519524SHoward Hinnanttemplate <class _InputIterator, class _RandomAccessIterator, class _Compare>
51603e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
51613e519524SHoward Hinnant_RandomAccessIterator
51623e519524SHoward Hinnantpartial_sort_copy(_InputIterator __first, _InputIterator __last,
51633e519524SHoward Hinnant                  _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
51643e519524SHoward Hinnant{
5165145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
51663e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
51673e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
51683e519524SHoward Hinnant    return __partial_sort_copy<_Comp_ref>(__first, __last, __result_first, __result_last, __c);
5169145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
51703e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
51713e519524SHoward Hinnant    return __partial_sort_copy<_Comp_ref>(__first, __last, __result_first, __result_last, __comp);
5172145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
51733e519524SHoward Hinnant}
51743e519524SHoward Hinnant
51753e519524SHoward Hinnanttemplate <class _InputIterator, class _RandomAccessIterator>
51763e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
51773e519524SHoward Hinnant_RandomAccessIterator
51783e519524SHoward Hinnantpartial_sort_copy(_InputIterator __first, _InputIterator __last,
51793e519524SHoward Hinnant                  _RandomAccessIterator __result_first, _RandomAccessIterator __result_last)
51803e519524SHoward Hinnant{
5181ce48a113SHoward Hinnant    return _VSTD::partial_sort_copy(__first, __last, __result_first, __result_last,
51823e519524SHoward Hinnant                                   __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
51833e519524SHoward Hinnant}
51843e519524SHoward Hinnant
51853e519524SHoward Hinnant// nth_element
51863e519524SHoward Hinnant
51873e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
51883e519524SHoward Hinnantvoid
51893e519524SHoward Hinnant__nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
51903e519524SHoward Hinnant{
51913e519524SHoward Hinnant    // _Compare is known to be a reference type
51923e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
51933e519524SHoward Hinnant    const difference_type __limit = 7;
51943e519524SHoward Hinnant    while (true)
51953e519524SHoward Hinnant    {
51963e519524SHoward Hinnant    __restart:
5197b34b4819SHoward Hinnant        if (__nth == __last)
5198b34b4819SHoward Hinnant            return;
51993e519524SHoward Hinnant        difference_type __len = __last - __first;
52003e519524SHoward Hinnant        switch (__len)
52013e519524SHoward Hinnant        {
52023e519524SHoward Hinnant        case 0:
52033e519524SHoward Hinnant        case 1:
52043e519524SHoward Hinnant            return;
52053e519524SHoward Hinnant        case 2:
52063e519524SHoward Hinnant            if (__comp(*--__last, *__first))
52073e519524SHoward Hinnant                swap(*__first, *__last);
52083e519524SHoward Hinnant            return;
52093e519524SHoward Hinnant        case 3:
52103e519524SHoward Hinnant            {
52113e519524SHoward Hinnant            _RandomAccessIterator __m = __first;
5212ce48a113SHoward Hinnant            _VSTD::__sort3<_Compare>(__first, ++__m, --__last, __comp);
52133e519524SHoward Hinnant            return;
52143e519524SHoward Hinnant            }
52153e519524SHoward Hinnant        }
52163e519524SHoward Hinnant        if (__len <= __limit)
52173e519524SHoward Hinnant        {
52183e519524SHoward Hinnant            __selection_sort<_Compare>(__first, __last, __comp);
52193e519524SHoward Hinnant            return;
52203e519524SHoward Hinnant        }
52213e519524SHoward Hinnant        // __len > __limit >= 3
52223e519524SHoward Hinnant        _RandomAccessIterator __m = __first + __len/2;
52233e519524SHoward Hinnant        _RandomAccessIterator __lm1 = __last;
5224ce48a113SHoward Hinnant        unsigned __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, --__lm1, __comp);
52253e519524SHoward Hinnant        // *__m is median
52263e519524SHoward Hinnant        // partition [__first, __m) < *__m and *__m <= [__m, __last)
52273e519524SHoward Hinnant        // (this inhibits tossing elements equivalent to __m around unnecessarily)
52283e519524SHoward Hinnant        _RandomAccessIterator __i = __first;
52293e519524SHoward Hinnant        _RandomAccessIterator __j = __lm1;
52303e519524SHoward Hinnant        // j points beyond range to be tested, *__lm1 is known to be <= *__m
52313e519524SHoward Hinnant        // The search going up is known to be guarded but the search coming down isn't.
52323e519524SHoward Hinnant        // Prime the downward search with a guard.
52333e519524SHoward Hinnant        if (!__comp(*__i, *__m))  // if *__first == *__m
52343e519524SHoward Hinnant        {
52353e519524SHoward Hinnant            // *__first == *__m, *__first doesn't go in first part
52363e519524SHoward Hinnant            // manually guard downward moving __j against __i
52373e519524SHoward Hinnant            while (true)
52383e519524SHoward Hinnant            {
52393e519524SHoward Hinnant                if (__i == --__j)
52403e519524SHoward Hinnant                {
52413e519524SHoward Hinnant                    // *__first == *__m, *__m <= all other elements
52423e519524SHoward Hinnant                    // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
52433e519524SHoward Hinnant                    ++__i;  // __first + 1
52443e519524SHoward Hinnant                    __j = __last;
52453e519524SHoward Hinnant                    if (!__comp(*__first, *--__j))  // we need a guard if *__first == *(__last-1)
52463e519524SHoward Hinnant                    {
52473e519524SHoward Hinnant                        while (true)
52483e519524SHoward Hinnant                        {
52493e519524SHoward Hinnant                            if (__i == __j)
52503e519524SHoward Hinnant                                return;  // [__first, __last) all equivalent elements
52513e519524SHoward Hinnant                            if (__comp(*__first, *__i))
52523e519524SHoward Hinnant                            {
52533e519524SHoward Hinnant                                swap(*__i, *__j);
52543e519524SHoward Hinnant                                ++__n_swaps;
52553e519524SHoward Hinnant                                ++__i;
52563e519524SHoward Hinnant                                break;
52573e519524SHoward Hinnant                            }
52583e519524SHoward Hinnant                            ++__i;
52593e519524SHoward Hinnant                        }
52603e519524SHoward Hinnant                    }
52613e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
52623e519524SHoward Hinnant                    if (__i == __j)
52633e519524SHoward Hinnant                        return;
52643e519524SHoward Hinnant                    while (true)
52653e519524SHoward Hinnant                    {
52663e519524SHoward Hinnant                        while (!__comp(*__first, *__i))
52673e519524SHoward Hinnant                            ++__i;
52683e519524SHoward Hinnant                        while (__comp(*__first, *--__j))
52693e519524SHoward Hinnant                            ;
52703e519524SHoward Hinnant                        if (__i >= __j)
52713e519524SHoward Hinnant                            break;
52723e519524SHoward Hinnant                        swap(*__i, *__j);
52733e519524SHoward Hinnant                        ++__n_swaps;
52743e519524SHoward Hinnant                        ++__i;
52753e519524SHoward Hinnant                    }
52763e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__i, __last)
52773e519524SHoward Hinnant                    // The first part is sorted,
52783e519524SHoward Hinnant                    if (__nth < __i)
52793e519524SHoward Hinnant                        return;
52803e519524SHoward Hinnant                    // __nth_element the secod part
52813e519524SHoward Hinnant                    // __nth_element<_Compare>(__i, __nth, __last, __comp);
52823e519524SHoward Hinnant                    __first = __i;
52833e519524SHoward Hinnant                    goto __restart;
52843e519524SHoward Hinnant                }
52853e519524SHoward Hinnant                if (__comp(*__j, *__m))
52863e519524SHoward Hinnant                {
52873e519524SHoward Hinnant                    swap(*__i, *__j);
52883e519524SHoward Hinnant                    ++__n_swaps;
52893e519524SHoward Hinnant                    break;  // found guard for downward moving __j, now use unguarded partition
52903e519524SHoward Hinnant                }
52913e519524SHoward Hinnant            }
52923e519524SHoward Hinnant        }
52933e519524SHoward Hinnant        ++__i;
52943e519524SHoward Hinnant        // j points beyond range to be tested, *__lm1 is known to be <= *__m
52953e519524SHoward Hinnant        // if not yet partitioned...
52963e519524SHoward Hinnant        if (__i < __j)
52973e519524SHoward Hinnant        {
52983e519524SHoward Hinnant            // known that *(__i - 1) < *__m
52993e519524SHoward Hinnant            while (true)
53003e519524SHoward Hinnant            {
53013e519524SHoward Hinnant                // __m still guards upward moving __i
53023e519524SHoward Hinnant                while (__comp(*__i, *__m))
53033e519524SHoward Hinnant                    ++__i;
53043e519524SHoward Hinnant                // It is now known that a guard exists for downward moving __j
53053e519524SHoward Hinnant                while (!__comp(*--__j, *__m))
53063e519524SHoward Hinnant                    ;
53073e519524SHoward Hinnant                if (__i >= __j)
53083e519524SHoward Hinnant                    break;
53093e519524SHoward Hinnant                swap(*__i, *__j);
53103e519524SHoward Hinnant                ++__n_swaps;
53113e519524SHoward Hinnant                // It is known that __m != __j
53123e519524SHoward Hinnant                // If __m just moved, follow it
53133e519524SHoward Hinnant                if (__m == __i)
53143e519524SHoward Hinnant                    __m = __j;
53153e519524SHoward Hinnant                ++__i;
53163e519524SHoward Hinnant            }
53173e519524SHoward Hinnant        }
53183e519524SHoward Hinnant        // [__first, __i) < *__m and *__m <= [__i, __last)
53193e519524SHoward Hinnant        if (__i != __m && __comp(*__m, *__i))
53203e519524SHoward Hinnant        {
53213e519524SHoward Hinnant            swap(*__i, *__m);
53223e519524SHoward Hinnant            ++__n_swaps;
53233e519524SHoward Hinnant        }
53243e519524SHoward Hinnant        // [__first, __i) < *__i and *__i <= [__i+1, __last)
53253e519524SHoward Hinnant        if (__nth == __i)
53263e519524SHoward Hinnant            return;
53273e519524SHoward Hinnant        if (__n_swaps == 0)
53283e519524SHoward Hinnant        {
53293e519524SHoward Hinnant            // We were given a perfectly partitioned sequence.  Coincidence?
53303e519524SHoward Hinnant            if (__nth < __i)
53313e519524SHoward Hinnant            {
53323e519524SHoward Hinnant                // Check for [__first, __i) already sorted
53333e519524SHoward Hinnant                __j = __m = __first;
53343e519524SHoward Hinnant                while (++__j != __i)
53353e519524SHoward Hinnant                {
53363e519524SHoward Hinnant                    if (__comp(*__j, *__m))
53373e519524SHoward Hinnant                        // not yet sorted, so sort
53383e519524SHoward Hinnant                        goto not_sorted;
53393e519524SHoward Hinnant                    __m = __j;
53403e519524SHoward Hinnant                }
53413e519524SHoward Hinnant                // [__first, __i) sorted
53423e519524SHoward Hinnant                return;
53433e519524SHoward Hinnant            }
53443e519524SHoward Hinnant            else
53453e519524SHoward Hinnant            {
53463e519524SHoward Hinnant                // Check for [__i, __last) already sorted
53473e519524SHoward Hinnant                __j = __m = __i;
53483e519524SHoward Hinnant                while (++__j != __last)
53493e519524SHoward Hinnant                {
53503e519524SHoward Hinnant                    if (__comp(*__j, *__m))
53513e519524SHoward Hinnant                        // not yet sorted, so sort
53523e519524SHoward Hinnant                        goto not_sorted;
53533e519524SHoward Hinnant                    __m = __j;
53543e519524SHoward Hinnant                }
53553e519524SHoward Hinnant                // [__i, __last) sorted
53563e519524SHoward Hinnant                return;
53573e519524SHoward Hinnant            }
53583e519524SHoward Hinnant        }
53593e519524SHoward Hinnantnot_sorted:
53603e519524SHoward Hinnant        // __nth_element on range containing __nth
53613e519524SHoward Hinnant        if (__nth < __i)
53623e519524SHoward Hinnant        {
53633e519524SHoward Hinnant            // __nth_element<_Compare>(__first, __nth, __i, __comp);
53643e519524SHoward Hinnant            __last = __i;
53653e519524SHoward Hinnant        }
53663e519524SHoward Hinnant        else
53673e519524SHoward Hinnant        {
53683e519524SHoward Hinnant            // __nth_element<_Compare>(__i+1, __nth, __last, __comp);
53693e519524SHoward Hinnant            __first = ++__i;
53703e519524SHoward Hinnant        }
53713e519524SHoward Hinnant    }
53723e519524SHoward Hinnant}
53733e519524SHoward Hinnant
53743e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
53753e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
53763e519524SHoward Hinnantvoid
53773e519524SHoward Hinnantnth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
53783e519524SHoward Hinnant{
5379145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
53803e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
53813e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
53823e519524SHoward Hinnant    __nth_element<_Comp_ref>(__first, __nth, __last, __c);
5383145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
53843e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
53853e519524SHoward Hinnant    __nth_element<_Comp_ref>(__first, __nth, __last, __comp);
5386145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
53873e519524SHoward Hinnant}
53883e519524SHoward Hinnant
53893e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
53903e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
53913e519524SHoward Hinnantvoid
53923e519524SHoward Hinnantnth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last)
53933e519524SHoward Hinnant{
5394ce48a113SHoward Hinnant    _VSTD::nth_element(__first, __nth, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
53953e519524SHoward Hinnant}
53963e519524SHoward Hinnant
53973e519524SHoward Hinnant// includes
53983e519524SHoward Hinnant
53993e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2>
54003e519524SHoward Hinnantbool
54013e519524SHoward Hinnant__includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
54023e519524SHoward Hinnant           _Compare __comp)
54033e519524SHoward Hinnant{
54043e519524SHoward Hinnant    for (; __first2 != __last2; ++__first1)
54053e519524SHoward Hinnant    {
54063e519524SHoward Hinnant        if (__first1 == __last1 || __comp(*__first2, *__first1))
54073e519524SHoward Hinnant            return false;
54083e519524SHoward Hinnant        if (!__comp(*__first1, *__first2))
54093e519524SHoward Hinnant            ++__first2;
54103e519524SHoward Hinnant    }
54113e519524SHoward Hinnant    return true;
54123e519524SHoward Hinnant}
54133e519524SHoward Hinnant
54143e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _Compare>
54153e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
54163e519524SHoward Hinnantbool
54173e519524SHoward Hinnantincludes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
54183e519524SHoward Hinnant         _Compare __comp)
54193e519524SHoward Hinnant{
5420145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
54213e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
54223e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
54233e519524SHoward Hinnant    return __includes<_Comp_ref>(__first1, __last1, __first2, __last2, __c);
5424145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
54253e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
54263e519524SHoward Hinnant    return __includes<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
5427145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
54283e519524SHoward Hinnant}
54293e519524SHoward Hinnant
54303e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
54313e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
54323e519524SHoward Hinnantbool
54333e519524SHoward Hinnantincludes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)
54343e519524SHoward Hinnant{
5435ce48a113SHoward Hinnant    return _VSTD::includes(__first1, __last1, __first2, __last2,
54363e519524SHoward Hinnant                          __less<typename iterator_traits<_InputIterator1>::value_type,
54373e519524SHoward Hinnant                                 typename iterator_traits<_InputIterator2>::value_type>());
54383e519524SHoward Hinnant}
54393e519524SHoward Hinnant
54403e519524SHoward Hinnant// set_union
54413e519524SHoward Hinnant
54423e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
54433e519524SHoward Hinnant_OutputIterator
54443e519524SHoward Hinnant__set_union(_InputIterator1 __first1, _InputIterator1 __last1,
54453e519524SHoward Hinnant            _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54463e519524SHoward Hinnant{
54473e519524SHoward Hinnant    for (; __first1 != __last1; ++__result)
54483e519524SHoward Hinnant    {
54493e519524SHoward Hinnant        if (__first2 == __last2)
5450ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
54513e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
54523e519524SHoward Hinnant        {
54533e519524SHoward Hinnant            *__result = *__first2;
54543e519524SHoward Hinnant            ++__first2;
54553e519524SHoward Hinnant        }
54563e519524SHoward Hinnant        else
54573e519524SHoward Hinnant        {
54583e519524SHoward Hinnant            if (!__comp(*__first1, *__first2))
54593e519524SHoward Hinnant                ++__first2;
546005da5b02SMarshall Clow            *__result = *__first1;
54613e519524SHoward Hinnant            ++__first1;
54623e519524SHoward Hinnant        }
54633e519524SHoward Hinnant    }
5464ce48a113SHoward Hinnant    return _VSTD::copy(__first2, __last2, __result);
54653e519524SHoward Hinnant}
54663e519524SHoward Hinnant
54673e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
54683e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
54693e519524SHoward Hinnant_OutputIterator
54703e519524SHoward Hinnantset_union(_InputIterator1 __first1, _InputIterator1 __last1,
54713e519524SHoward Hinnant          _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54723e519524SHoward Hinnant{
5473145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
54743e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
54753e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
54763e519524SHoward Hinnant    return __set_union<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __c);
5477145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
54783e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
54793e519524SHoward Hinnant    return __set_union<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5480145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
54813e519524SHoward Hinnant}
54823e519524SHoward Hinnant
54833e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
54843e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
54853e519524SHoward Hinnant_OutputIterator
54863e519524SHoward Hinnantset_union(_InputIterator1 __first1, _InputIterator1 __last1,
54873e519524SHoward Hinnant          _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
54883e519524SHoward Hinnant{
5489ce48a113SHoward Hinnant    return _VSTD::set_union(__first1, __last1, __first2, __last2, __result,
54903e519524SHoward Hinnant                          __less<typename iterator_traits<_InputIterator1>::value_type,
54913e519524SHoward Hinnant                                 typename iterator_traits<_InputIterator2>::value_type>());
54923e519524SHoward Hinnant}
54933e519524SHoward Hinnant
54943e519524SHoward Hinnant// set_intersection
54953e519524SHoward Hinnant
54963e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
54973e519524SHoward Hinnant_OutputIterator
54983e519524SHoward Hinnant__set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54993e519524SHoward Hinnant                   _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
55003e519524SHoward Hinnant{
55013e519524SHoward Hinnant    while (__first1 != __last1 && __first2 != __last2)
55023e519524SHoward Hinnant    {
55033e519524SHoward Hinnant        if (__comp(*__first1, *__first2))
55043e519524SHoward Hinnant            ++__first1;
55053e519524SHoward Hinnant        else
55063e519524SHoward Hinnant        {
55073e519524SHoward Hinnant            if (!__comp(*__first2, *__first1))
55083e519524SHoward Hinnant            {
55093e519524SHoward Hinnant                *__result = *__first1;
55103e519524SHoward Hinnant                ++__result;
55113e519524SHoward Hinnant                ++__first1;
55123e519524SHoward Hinnant            }
55133e519524SHoward Hinnant            ++__first2;
55143e519524SHoward Hinnant        }
55153e519524SHoward Hinnant    }
55163e519524SHoward Hinnant    return __result;
55173e519524SHoward Hinnant}
55183e519524SHoward Hinnant
55193e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
55203e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
55213e519524SHoward Hinnant_OutputIterator
55223e519524SHoward Hinnantset_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
55233e519524SHoward Hinnant                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
55243e519524SHoward Hinnant{
5525145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
55263e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
55273e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
55283e519524SHoward Hinnant    return __set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __c);
5529145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
55303e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
55313e519524SHoward Hinnant    return __set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5532145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
55333e519524SHoward Hinnant}
55343e519524SHoward Hinnant
55353e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
55363e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
55373e519524SHoward Hinnant_OutputIterator
55383e519524SHoward Hinnantset_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
55393e519524SHoward Hinnant                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
55403e519524SHoward Hinnant{
5541ce48a113SHoward Hinnant    return _VSTD::set_intersection(__first1, __last1, __first2, __last2, __result,
55423e519524SHoward Hinnant                                  __less<typename iterator_traits<_InputIterator1>::value_type,
55433e519524SHoward Hinnant                                         typename iterator_traits<_InputIterator2>::value_type>());
55443e519524SHoward Hinnant}
55453e519524SHoward Hinnant
55463e519524SHoward Hinnant// set_difference
55473e519524SHoward Hinnant
55483e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
55493e519524SHoward Hinnant_OutputIterator
55503e519524SHoward Hinnant__set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55513e519524SHoward Hinnant                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
55523e519524SHoward Hinnant{
55533e519524SHoward Hinnant    while (__first1 != __last1)
55543e519524SHoward Hinnant    {
55553e519524SHoward Hinnant        if (__first2 == __last2)
5556ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
55573e519524SHoward Hinnant        if (__comp(*__first1, *__first2))
55583e519524SHoward Hinnant        {
55593e519524SHoward Hinnant            *__result = *__first1;
55603e519524SHoward Hinnant            ++__result;
55613e519524SHoward Hinnant            ++__first1;
55623e519524SHoward Hinnant        }
55633e519524SHoward Hinnant        else
55643e519524SHoward Hinnant        {
55653e519524SHoward Hinnant            if (!__comp(*__first2, *__first1))
55663e519524SHoward Hinnant                ++__first1;
55673e519524SHoward Hinnant            ++__first2;
55683e519524SHoward Hinnant        }
55693e519524SHoward Hinnant    }
55703e519524SHoward Hinnant    return __result;
55713e519524SHoward Hinnant}
55723e519524SHoward Hinnant
55733e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
55743e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
55753e519524SHoward Hinnant_OutputIterator
55763e519524SHoward Hinnantset_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55773e519524SHoward Hinnant               _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
55783e519524SHoward Hinnant{
5579145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
55803e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
55813e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
55823e519524SHoward Hinnant    return __set_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __c);
5583145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
55843e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
55853e519524SHoward Hinnant    return __set_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5586145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
55873e519524SHoward Hinnant}
55883e519524SHoward Hinnant
55893e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
55903e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
55913e519524SHoward Hinnant_OutputIterator
55923e519524SHoward Hinnantset_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55933e519524SHoward Hinnant               _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
55943e519524SHoward Hinnant{
5595ce48a113SHoward Hinnant    return _VSTD::set_difference(__first1, __last1, __first2, __last2, __result,
55963e519524SHoward Hinnant                                __less<typename iterator_traits<_InputIterator1>::value_type,
55973e519524SHoward Hinnant                                       typename iterator_traits<_InputIterator2>::value_type>());
55983e519524SHoward Hinnant}
55993e519524SHoward Hinnant
56003e519524SHoward Hinnant// set_symmetric_difference
56013e519524SHoward Hinnant
56023e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
56033e519524SHoward Hinnant_OutputIterator
56043e519524SHoward Hinnant__set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
56053e519524SHoward Hinnant                           _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
56063e519524SHoward Hinnant{
56073e519524SHoward Hinnant    while (__first1 != __last1)
56083e519524SHoward Hinnant    {
56093e519524SHoward Hinnant        if (__first2 == __last2)
5610ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
56113e519524SHoward Hinnant        if (__comp(*__first1, *__first2))
56123e519524SHoward Hinnant        {
56133e519524SHoward Hinnant            *__result = *__first1;
56143e519524SHoward Hinnant            ++__result;
56153e519524SHoward Hinnant            ++__first1;
56163e519524SHoward Hinnant        }
56173e519524SHoward Hinnant        else
56183e519524SHoward Hinnant        {
56193e519524SHoward Hinnant            if (__comp(*__first2, *__first1))
56203e519524SHoward Hinnant            {
56213e519524SHoward Hinnant                *__result = *__first2;
56223e519524SHoward Hinnant                ++__result;
56233e519524SHoward Hinnant            }
56243e519524SHoward Hinnant            else
56253e519524SHoward Hinnant                ++__first1;
56263e519524SHoward Hinnant            ++__first2;
56273e519524SHoward Hinnant        }
56283e519524SHoward Hinnant    }
5629ce48a113SHoward Hinnant    return _VSTD::copy(__first2, __last2, __result);
56303e519524SHoward Hinnant}
56313e519524SHoward Hinnant
56323e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
56333e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
56343e519524SHoward Hinnant_OutputIterator
56353e519524SHoward Hinnantset_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
56363e519524SHoward Hinnant                         _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
56373e519524SHoward Hinnant{
5638145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
56393e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
56403e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
56413e519524SHoward Hinnant    return __set_symmetric_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __c);
5642145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
56433e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
56443e519524SHoward Hinnant    return __set_symmetric_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
5645145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
56463e519524SHoward Hinnant}
56473e519524SHoward Hinnant
56483e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
56493e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
56503e519524SHoward Hinnant_OutputIterator
56513e519524SHoward Hinnantset_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
56523e519524SHoward Hinnant                         _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
56533e519524SHoward Hinnant{
5654ce48a113SHoward Hinnant    return _VSTD::set_symmetric_difference(__first1, __last1, __first2, __last2, __result,
56553e519524SHoward Hinnant                                          __less<typename iterator_traits<_InputIterator1>::value_type,
56563e519524SHoward Hinnant                                                 typename iterator_traits<_InputIterator2>::value_type>());
56573e519524SHoward Hinnant}
56583e519524SHoward Hinnant
56593e519524SHoward Hinnant// lexicographical_compare
56603e519524SHoward Hinnant
56613e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2>
56621b9a4ffdSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
56633e519524SHoward Hinnant__lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
56643e519524SHoward Hinnant                          _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
56653e519524SHoward Hinnant{
5666910285b2SEric Fiselier    for (; __first2 != __last2; ++__first1, (void) ++__first2)
56673e519524SHoward Hinnant    {
56683e519524SHoward Hinnant        if (__first1 == __last1 || __comp(*__first1, *__first2))
56693e519524SHoward Hinnant            return true;
56703e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
56713e519524SHoward Hinnant            return false;
56723e519524SHoward Hinnant    }
56733e519524SHoward Hinnant    return false;
56743e519524SHoward Hinnant}
56753e519524SHoward Hinnant
56763e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _Compare>
56771b9a4ffdSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
56783e519524SHoward Hinnantbool
56793e519524SHoward Hinnantlexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
56803e519524SHoward Hinnant                        _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
56813e519524SHoward Hinnant{
5682145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
56833e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
56843e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
56853e519524SHoward Hinnant    return __lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __c);
5686145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
56873e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
56883e519524SHoward Hinnant    return __lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
5689145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
56903e519524SHoward Hinnant}
56913e519524SHoward Hinnant
56923e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
56931b9a4ffdSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
56943e519524SHoward Hinnantbool
56953e519524SHoward Hinnantlexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
56963e519524SHoward Hinnant                        _InputIterator2 __first2, _InputIterator2 __last2)
56973e519524SHoward Hinnant{
5698ce48a113SHoward Hinnant    return _VSTD::lexicographical_compare(__first1, __last1, __first2, __last2,
56993e519524SHoward Hinnant                                         __less<typename iterator_traits<_InputIterator1>::value_type,
57003e519524SHoward Hinnant                                                typename iterator_traits<_InputIterator2>::value_type>());
57013e519524SHoward Hinnant}
57023e519524SHoward Hinnant
57033e519524SHoward Hinnant// next_permutation
57043e519524SHoward Hinnant
57053e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
57063e519524SHoward Hinnantbool
57073e519524SHoward Hinnant__next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
57083e519524SHoward Hinnant{
57093e519524SHoward Hinnant    _BidirectionalIterator __i = __last;
57103e519524SHoward Hinnant    if (__first == __last || __first == --__i)
57113e519524SHoward Hinnant        return false;
57123e519524SHoward Hinnant    while (true)
57133e519524SHoward Hinnant    {
57143e519524SHoward Hinnant        _BidirectionalIterator __ip1 = __i;
57153e519524SHoward Hinnant        if (__comp(*--__i, *__ip1))
57163e519524SHoward Hinnant        {
57173e519524SHoward Hinnant            _BidirectionalIterator __j = __last;
57183e519524SHoward Hinnant            while (!__comp(*__i, *--__j))
57193e519524SHoward Hinnant                ;
57203e519524SHoward Hinnant            swap(*__i, *__j);
5721ce48a113SHoward Hinnant            _VSTD::reverse(__ip1, __last);
57223e519524SHoward Hinnant            return true;
57233e519524SHoward Hinnant        }
57243e519524SHoward Hinnant        if (__i == __first)
57253e519524SHoward Hinnant        {
5726ce48a113SHoward Hinnant            _VSTD::reverse(__first, __last);
57273e519524SHoward Hinnant            return false;
57283e519524SHoward Hinnant        }
57293e519524SHoward Hinnant    }
57303e519524SHoward Hinnant}
57313e519524SHoward Hinnant
57323e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _Compare>
57333e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
57343e519524SHoward Hinnantbool
57353e519524SHoward Hinnantnext_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
57363e519524SHoward Hinnant{
5737145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
57383e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
57393e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
57403e519524SHoward Hinnant    return __next_permutation<_Comp_ref>(__first, __last, __c);
5741145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
57423e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
57433e519524SHoward Hinnant    return __next_permutation<_Comp_ref>(__first, __last, __comp);
5744145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
57453e519524SHoward Hinnant}
57463e519524SHoward Hinnant
57473e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
57483e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
57493e519524SHoward Hinnantbool
57503e519524SHoward Hinnantnext_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
57513e519524SHoward Hinnant{
5752ce48a113SHoward Hinnant    return _VSTD::next_permutation(__first, __last,
57533e519524SHoward Hinnant                                  __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
57543e519524SHoward Hinnant}
57553e519524SHoward Hinnant
57563e519524SHoward Hinnant// prev_permutation
57573e519524SHoward Hinnant
57583e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
57593e519524SHoward Hinnantbool
57603e519524SHoward Hinnant__prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
57613e519524SHoward Hinnant{
57623e519524SHoward Hinnant    _BidirectionalIterator __i = __last;
57633e519524SHoward Hinnant    if (__first == __last || __first == --__i)
57643e519524SHoward Hinnant        return false;
57653e519524SHoward Hinnant    while (true)
57663e519524SHoward Hinnant    {
57673e519524SHoward Hinnant        _BidirectionalIterator __ip1 = __i;
57683e519524SHoward Hinnant        if (__comp(*__ip1, *--__i))
57693e519524SHoward Hinnant        {
57703e519524SHoward Hinnant            _BidirectionalIterator __j = __last;
57713e519524SHoward Hinnant            while (!__comp(*--__j, *__i))
57723e519524SHoward Hinnant                ;
57733e519524SHoward Hinnant            swap(*__i, *__j);
5774ce48a113SHoward Hinnant            _VSTD::reverse(__ip1, __last);
57753e519524SHoward Hinnant            return true;
57763e519524SHoward Hinnant        }
57773e519524SHoward Hinnant        if (__i == __first)
57783e519524SHoward Hinnant        {
5779ce48a113SHoward Hinnant            _VSTD::reverse(__first, __last);
57803e519524SHoward Hinnant            return false;
57813e519524SHoward Hinnant        }
57823e519524SHoward Hinnant    }
57833e519524SHoward Hinnant}
57843e519524SHoward Hinnant
57853e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _Compare>
57863e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
57873e519524SHoward Hinnantbool
57883e519524SHoward Hinnantprev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
57893e519524SHoward Hinnant{
5790145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
57913e519524SHoward Hinnant    typedef typename add_lvalue_reference<__debug_less<_Compare> >::type _Comp_ref;
57923e519524SHoward Hinnant    __debug_less<_Compare> __c(__comp);
57933e519524SHoward Hinnant    return __prev_permutation<_Comp_ref>(__first, __last, __c);
5794145afa17SHoward Hinnant#else  // _LIBCPP_DEBUG
57953e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
57963e519524SHoward Hinnant    return __prev_permutation<_Comp_ref>(__first, __last, __comp);
5797145afa17SHoward Hinnant#endif  // _LIBCPP_DEBUG
57983e519524SHoward Hinnant}
57993e519524SHoward Hinnant
58003e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
58013e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
58023e519524SHoward Hinnantbool
58033e519524SHoward Hinnantprev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
58043e519524SHoward Hinnant{
5805ce48a113SHoward Hinnant    return _VSTD::prev_permutation(__first, __last,
58063e519524SHoward Hinnant                                  __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
58073e519524SHoward Hinnant}
58083e519524SHoward Hinnant
58093e519524SHoward Hinnant_LIBCPP_END_NAMESPACE_STD
58103e519524SHoward Hinnant
5811a016efb1SEric Fiselier_LIBCPP_POP_MACROS
5812a016efb1SEric Fiselier
58133e519524SHoward Hinnant#endif  // _LIBCPP_ALGORITHM
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