13e519524SHoward Hinnant// -*- C++ -*-
23e519524SHoward Hinnant//===-------------------------- algorithm ---------------------------------===//
33e519524SHoward Hinnant//
457b08b09SChandler Carruth// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
557b08b09SChandler Carruth// See https://llvm.org/LICENSE.txt for license information.
657b08b09SChandler Carruth// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
73e519524SHoward Hinnant//
83e519524SHoward Hinnant//===----------------------------------------------------------------------===//
93e519524SHoward Hinnant
103e519524SHoward Hinnant#ifndef _LIBCPP_ALGORITHM
113e519524SHoward Hinnant#define _LIBCPP_ALGORITHM
123e519524SHoward Hinnant
133e519524SHoward Hinnant/*
143e519524SHoward Hinnant    algorithm synopsis
153e519524SHoward Hinnant
163e519524SHoward Hinnant#include <initializer_list>
173e519524SHoward Hinnant
183e519524SHoward Hinnantnamespace std
193e519524SHoward Hinnant{
203e519524SHoward Hinnant
213e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
22706ffef7SMarshall Clow    constexpr bool     // constexpr in C++20
233e519524SHoward Hinnant    all_of(InputIterator first, InputIterator last, Predicate pred);
243e519524SHoward Hinnant
253e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
26706ffef7SMarshall Clow    constexpr bool     // constexpr in C++20
273e519524SHoward Hinnant    any_of(InputIterator first, InputIterator last, Predicate pred);
283e519524SHoward Hinnant
293e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
30706ffef7SMarshall Clow    constexpr bool     // constexpr in C++20
313e519524SHoward Hinnant    none_of(InputIterator first, InputIterator last, Predicate pred);
323e519524SHoward Hinnant
333e519524SHoward Hinnanttemplate <class InputIterator, class Function>
341b9a4ffdSMarshall Clow    constexpr Function          // constexpr in C++20
353e519524SHoward Hinnant    for_each(InputIterator first, InputIterator last, Function f);
363e519524SHoward Hinnant
37d5c65ffaSMarshall Clowtemplate<class InputIterator, class Size, class Function>
381b9a4ffdSMarshall Clow    constexpr InputIterator     // constexpr in C++20
391b9a4ffdSMarshall Clow    for_each_n(InputIterator first, Size n, Function f); // C++17
40d5c65ffaSMarshall Clow
413e519524SHoward Hinnanttemplate <class InputIterator, class T>
4249c7643cSMarshall Clow    constexpr InputIterator     // constexpr in C++20
433e519524SHoward Hinnant    find(InputIterator first, InputIterator last, const T& value);
443e519524SHoward Hinnant
453e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
4649c7643cSMarshall Clow    constexpr InputIterator     // constexpr in C++20
473e519524SHoward Hinnant    find_if(InputIterator first, InputIterator last, Predicate pred);
483e519524SHoward Hinnant
493e519524SHoward Hinnanttemplate<class InputIterator, class Predicate>
508694428eSMarshall Clow    InputIterator               // constexpr in C++20
513e519524SHoward Hinnant    find_if_not(InputIterator first, InputIterator last, Predicate pred);
523e519524SHoward Hinnant
533e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
548694428eSMarshall Clow    ForwardIterator1            // constexpr in C++20
553e519524SHoward Hinnant    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
563e519524SHoward Hinnant             ForwardIterator2 first2, ForwardIterator2 last2);
573e519524SHoward Hinnant
583e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
598694428eSMarshall Clow    ForwardIterator1            // constexpr in C++20
603e519524SHoward Hinnant    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
613e519524SHoward Hinnant             ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
623e519524SHoward Hinnant
633e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
648694428eSMarshall Clow    constexpr ForwardIterator1  // constexpr in C++20
653e519524SHoward Hinnant    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
663e519524SHoward Hinnant                  ForwardIterator2 first2, ForwardIterator2 last2);
673e519524SHoward Hinnant
683e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
698694428eSMarshall Clow    constexpr ForwardIterator1  // constexpr in C++20
703e519524SHoward Hinnant    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
713e519524SHoward Hinnant                  ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
723e519524SHoward Hinnant
733e519524SHoward Hinnanttemplate <class ForwardIterator>
748694428eSMarshall Clow    constexpr ForwardIterator   // constexpr in C++20
753e519524SHoward Hinnant    adjacent_find(ForwardIterator first, ForwardIterator last);
763e519524SHoward Hinnant
773e519524SHoward Hinnanttemplate <class ForwardIterator, class BinaryPredicate>
788694428eSMarshall Clow    constexpr ForwardIterator   // constexpr in C++20
793e519524SHoward Hinnant    adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
803e519524SHoward Hinnant
813e519524SHoward Hinnanttemplate <class InputIterator, class T>
82056f15e3SMarshall Clow    constexpr typename iterator_traits<InputIterator>::difference_type  // constexpr in C++20
833e519524SHoward Hinnant    count(InputIterator first, InputIterator last, const T& value);
843e519524SHoward Hinnant
853e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
86056f15e3SMarshall Clow    constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
873e519524SHoward Hinnant    count_if(InputIterator first, InputIterator last, Predicate pred);
883e519524SHoward Hinnant
893e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
906538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
913e519524SHoward Hinnant    mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
923e519524SHoward Hinnant
930b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2>
946538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
950b0bbd2fSMarshall Clow    mismatch(InputIterator1 first1, InputIterator1 last1,
960b0bbd2fSMarshall Clow             InputIterator2 first2, InputIterator2 last2); // **C++14**
970b0bbd2fSMarshall Clow
983e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
996538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
1003e519524SHoward Hinnant    mismatch(InputIterator1 first1, InputIterator1 last1,
1013e519524SHoward Hinnant             InputIterator2 first2, BinaryPredicate pred);
1023e519524SHoward Hinnant
1030b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1046538e28dSMarshall Clow    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
1050b0bbd2fSMarshall Clow    mismatch(InputIterator1 first1, InputIterator1 last1,
1060b0bbd2fSMarshall Clow             InputIterator2 first2, InputIterator2 last2,
1070b0bbd2fSMarshall Clow             BinaryPredicate pred); // **C++14**
1080b0bbd2fSMarshall Clow
1093e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
1106538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1113e519524SHoward Hinnant    equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
1123e519524SHoward Hinnant
1130b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2>
1146538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1150b0bbd2fSMarshall Clow    equal(InputIterator1 first1, InputIterator1 last1,
1160b0bbd2fSMarshall Clow          InputIterator2 first2, InputIterator2 last2); // **C++14**
1170b0bbd2fSMarshall Clow
1183e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1196538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1203e519524SHoward Hinnant    equal(InputIterator1 first1, InputIterator1 last1,
1213e519524SHoward Hinnant          InputIterator2 first2, BinaryPredicate pred);
1223e519524SHoward Hinnant
1230b0bbd2fSMarshall Clowtemplate <class InputIterator1, class InputIterator2, class BinaryPredicate>
1246538e28dSMarshall Clow    constexpr bool      // constexpr in C++20
1250b0bbd2fSMarshall Clow    equal(InputIterator1 first1, InputIterator1 last1,
1260b0bbd2fSMarshall Clow          InputIterator2 first2, InputIterator2 last2,
1270b0bbd2fSMarshall Clow          BinaryPredicate pred); // **C++14**
1280b0bbd2fSMarshall Clow
1293e519524SHoward Hinnanttemplate<class ForwardIterator1, class ForwardIterator2>
13049c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1313e519524SHoward Hinnant    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1323e519524SHoward Hinnant                   ForwardIterator2 first2);
1333e519524SHoward Hinnant
1340b0bbd2fSMarshall Clowtemplate<class ForwardIterator1, class ForwardIterator2>
13549c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1360b0bbd2fSMarshall Clow    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1370b0bbd2fSMarshall Clow                   ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
1380b0bbd2fSMarshall Clow
1393e519524SHoward Hinnanttemplate<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
14049c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1413e519524SHoward Hinnant    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1423e519524SHoward Hinnant                   ForwardIterator2 first2, BinaryPredicate pred);
1433e519524SHoward Hinnant
1440b0bbd2fSMarshall Clowtemplate<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
14549c7643cSMarshall Clow    constexpr bool      // constexpr in C++20
1460b0bbd2fSMarshall Clow    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
1470b0bbd2fSMarshall Clow                   ForwardIterator2 first2, ForwardIterator2 last2,
1480b0bbd2fSMarshall Clow                   BinaryPredicate pred);  // **C++14**
1490b0bbd2fSMarshall Clow
1503e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
15112f0a779SMarshall Clow    constexpr ForwardIterator1      // constexpr in C++20
1523e519524SHoward Hinnant    search(ForwardIterator1 first1, ForwardIterator1 last1,
1533e519524SHoward Hinnant           ForwardIterator2 first2, ForwardIterator2 last2);
1543e519524SHoward Hinnant
1553e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
15612f0a779SMarshall Clow    constexpr ForwardIterator1      // constexpr in C++20
1573e519524SHoward Hinnant    search(ForwardIterator1 first1, ForwardIterator1 last1,
1583e519524SHoward Hinnant           ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
1593e519524SHoward Hinnant
1603e519524SHoward Hinnanttemplate <class ForwardIterator, class Size, class T>
16112f0a779SMarshall Clow    constexpr ForwardIterator       // constexpr in C++20
1623e519524SHoward Hinnant    search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
1633e519524SHoward Hinnant
1643e519524SHoward Hinnanttemplate <class ForwardIterator, class Size, class T, class BinaryPredicate>
16512f0a779SMarshall Clow    constexpr ForwardIterator       // constexpr in C++20
1663e519524SHoward Hinnant    search_n(ForwardIterator first, ForwardIterator last,
1673e519524SHoward Hinnant             Size count, const T& value, BinaryPredicate pred);
1683e519524SHoward Hinnant
1693e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator>
1703e519524SHoward Hinnant    OutputIterator
1713e519524SHoward Hinnant    copy(InputIterator first, InputIterator last, OutputIterator result);
1723e519524SHoward Hinnant
1733e519524SHoward Hinnanttemplate<class InputIterator, class OutputIterator, class Predicate>
1743e519524SHoward Hinnant    OutputIterator
1753e519524SHoward Hinnant    copy_if(InputIterator first, InputIterator last,
1763e519524SHoward Hinnant            OutputIterator result, Predicate pred);
1773e519524SHoward Hinnant
1783e519524SHoward Hinnanttemplate<class InputIterator, class Size, class OutputIterator>
1793e519524SHoward Hinnant    OutputIterator
1803e519524SHoward Hinnant    copy_n(InputIterator first, Size n, OutputIterator result);
1813e519524SHoward Hinnant
1823e519524SHoward Hinnanttemplate <class BidirectionalIterator1, class BidirectionalIterator2>
1833e519524SHoward Hinnant    BidirectionalIterator2
1843e519524SHoward Hinnant    copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
1853e519524SHoward Hinnant                  BidirectionalIterator2 result);
1863e519524SHoward Hinnant
1873e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
1883e519524SHoward Hinnant    ForwardIterator2
1893e519524SHoward Hinnant    swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
1903e519524SHoward Hinnant
1913e519524SHoward Hinnanttemplate <class ForwardIterator1, class ForwardIterator2>
1923e519524SHoward Hinnant    void
1933e519524SHoward Hinnant    iter_swap(ForwardIterator1 a, ForwardIterator2 b);
1943e519524SHoward Hinnant
1953e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class UnaryOperation>
19699894b61SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
1973e519524SHoward Hinnant    transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
1983e519524SHoward Hinnant
1993e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
20099894b61SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2013e519524SHoward Hinnant    transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
2023e519524SHoward Hinnant              OutputIterator result, BinaryOperation binary_op);
2033e519524SHoward Hinnant
2043e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
20512c7423fSMarshall Clow    constexpr void      // constexpr in C++20
2063e519524SHoward Hinnant    replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
2073e519524SHoward Hinnant
2083e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate, class T>
20912c7423fSMarshall Clow    constexpr void      // constexpr in C++20
2103e519524SHoward Hinnant    replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
2113e519524SHoward Hinnant
2123e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class T>
21312c7423fSMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2143e519524SHoward Hinnant    replace_copy(InputIterator first, InputIterator last, OutputIterator result,
2153e519524SHoward Hinnant                 const T& old_value, const T& new_value);
2163e519524SHoward Hinnant
2173e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class Predicate, class T>
21812c7423fSMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2193e519524SHoward Hinnant    replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
2203e519524SHoward Hinnant
2213e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
2224bfb9313SMarshall Clow    constexpr void      // constexpr in C++20
2233e519524SHoward Hinnant    fill(ForwardIterator first, ForwardIterator last, const T& value);
2243e519524SHoward Hinnant
2253e519524SHoward Hinnanttemplate <class OutputIterator, class Size, class T>
2264bfb9313SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2273e519524SHoward Hinnant    fill_n(OutputIterator first, Size n, const T& value);
2283e519524SHoward Hinnant
2293e519524SHoward Hinnanttemplate <class ForwardIterator, class Generator>
2304bfb9313SMarshall Clow    constexpr void      // constexpr in C++20
2313e519524SHoward Hinnant    generate(ForwardIterator first, ForwardIterator last, Generator gen);
2323e519524SHoward Hinnant
2333e519524SHoward Hinnanttemplate <class OutputIterator, class Size, class Generator>
2344bfb9313SMarshall Clow    constexpr OutputIterator      // constexpr in C++20
2353e519524SHoward Hinnant    generate_n(OutputIterator first, Size n, Generator gen);
2363e519524SHoward Hinnant
2373e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
238e8ea8296SMarshall Clow    constexpr ForwardIterator     // constexpr in C++20
2393e519524SHoward Hinnant    remove(ForwardIterator first, ForwardIterator last, const T& value);
2403e519524SHoward Hinnant
2413e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate>
242e8ea8296SMarshall Clow    constexpr ForwardIterator     // constexpr in C++20
2433e519524SHoward Hinnant    remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
2443e519524SHoward Hinnant
2453e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class T>
246e8ea8296SMarshall Clow    constexpr OutputIterator     // constexpr in C++20
2473e519524SHoward Hinnant    remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
2483e519524SHoward Hinnant
2493e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class Predicate>
250e8ea8296SMarshall Clow    constexpr OutputIterator     // constexpr in C++20
2513e519524SHoward Hinnant    remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
2523e519524SHoward Hinnant
2533e519524SHoward Hinnanttemplate <class ForwardIterator>
2543e519524SHoward Hinnant    ForwardIterator
2553e519524SHoward Hinnant    unique(ForwardIterator first, ForwardIterator last);
2563e519524SHoward Hinnant
2573e519524SHoward Hinnanttemplate <class ForwardIterator, class BinaryPredicate>
2583e519524SHoward Hinnant    ForwardIterator
2593e519524SHoward Hinnant    unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
2603e519524SHoward Hinnant
2613e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator>
2623e519524SHoward Hinnant    OutputIterator
2633e519524SHoward Hinnant    unique_copy(InputIterator first, InputIterator last, OutputIterator result);
2643e519524SHoward Hinnant
2653e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator, class BinaryPredicate>
2663e519524SHoward Hinnant    OutputIterator
2673e519524SHoward Hinnant    unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
2683e519524SHoward Hinnant
2693e519524SHoward Hinnanttemplate <class BidirectionalIterator>
2703e519524SHoward Hinnant    void
2713e519524SHoward Hinnant    reverse(BidirectionalIterator first, BidirectionalIterator last);
2723e519524SHoward Hinnant
2733e519524SHoward Hinnanttemplate <class BidirectionalIterator, class OutputIterator>
274e8ea8296SMarshall Clow    constexpr OutputIterator       // constexpr in C++20
2753e519524SHoward Hinnant    reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
2763e519524SHoward Hinnant
2773e519524SHoward Hinnanttemplate <class ForwardIterator>
2783e519524SHoward Hinnant    ForwardIterator
2793e519524SHoward Hinnant    rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
2803e519524SHoward Hinnant
2813e519524SHoward Hinnanttemplate <class ForwardIterator, class OutputIterator>
2823e519524SHoward Hinnant    OutputIterator
2833e519524SHoward Hinnant    rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
2843e519524SHoward Hinnant
2853e519524SHoward Hinnanttemplate <class RandomAccessIterator>
2863e519524SHoward Hinnant    void
2870f37a410SMarshall Clow    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
2883e519524SHoward Hinnant
2893e519524SHoward Hinnanttemplate <class RandomAccessIterator, class RandomNumberGenerator>
2903e519524SHoward Hinnant    void
29106965c1fSMarshall Clow    random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
2920f37a410SMarshall Clow                   RandomNumberGenerator& rand);  // deprecated in C++14, removed in C++17
2933e519524SHoward Hinnant
294e7154709SEric Fiseliertemplate<class PopulationIterator, class SampleIterator,
295e7154709SEric Fiselier         class Distance, class UniformRandomBitGenerator>
296e7154709SEric Fiselier    SampleIterator sample(PopulationIterator first, PopulationIterator last,
297e7154709SEric Fiselier                          SampleIterator out, Distance n,
298e7154709SEric Fiselier                          UniformRandomBitGenerator&& g); // C++17
299e7154709SEric Fiselier
300f9d540b0SHoward Hinnanttemplate<class RandomAccessIterator, class UniformRandomNumberGenerator>
301f9d540b0SHoward Hinnant    void shuffle(RandomAccessIterator first, RandomAccessIterator last,
302fb340102SHoward Hinnant                 UniformRandomNumberGenerator&& g);
303f9d540b0SHoward Hinnant
3043e519524SHoward Hinnanttemplate <class InputIterator, class Predicate>
30549c7643cSMarshall Clow    constexpr bool  // constexpr in C++20
3063e519524SHoward Hinnant    is_partitioned(InputIterator first, InputIterator last, Predicate pred);
3073e519524SHoward Hinnant
3083e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate>
3093e519524SHoward Hinnant    ForwardIterator
3103e519524SHoward Hinnant    partition(ForwardIterator first, ForwardIterator last, Predicate pred);
3113e519524SHoward Hinnant
3123e519524SHoward Hinnanttemplate <class InputIterator, class OutputIterator1,
3133e519524SHoward Hinnant          class OutputIterator2, class Predicate>
3141b9a4ffdSMarshall Clow    constexpr pair<OutputIterator1, OutputIterator2>   // constexpr in C++20
3153e519524SHoward Hinnant    partition_copy(InputIterator first, InputIterator last,
3163e519524SHoward Hinnant                   OutputIterator1 out_true, OutputIterator2 out_false,
3173e519524SHoward Hinnant                   Predicate pred);
3183e519524SHoward Hinnant
3193e519524SHoward Hinnanttemplate <class ForwardIterator, class Predicate>
3203e519524SHoward Hinnant    ForwardIterator
3213e519524SHoward Hinnant    stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
3223e519524SHoward Hinnant
3233e519524SHoward Hinnanttemplate<class ForwardIterator, class Predicate>
324d57c03ddSMarshall Clow    constexpr ForwardIterator  // constexpr in C++20
3253e519524SHoward Hinnant    partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
3263e519524SHoward Hinnant
3273e519524SHoward Hinnanttemplate <class ForwardIterator>
32849c7643cSMarshall Clow    constexpr bool  // constexpr in C++20
3293e519524SHoward Hinnant    is_sorted(ForwardIterator first, ForwardIterator last);
3303e519524SHoward Hinnant
3313e519524SHoward Hinnanttemplate <class ForwardIterator, class Compare>
3323e519524SHoward Hinnant    bool
3333e519524SHoward Hinnant    is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
3343e519524SHoward Hinnant
3353e519524SHoward Hinnanttemplate<class ForwardIterator>
336056f15e3SMarshall Clow    constexpr ForwardIterator    // constexpr in C++20
3373e519524SHoward Hinnant    is_sorted_until(ForwardIterator first, ForwardIterator last);
3383e519524SHoward Hinnant
3393e519524SHoward Hinnanttemplate <class ForwardIterator, class Compare>
340056f15e3SMarshall Clow    constexpr ForwardIterator    // constexpr in C++20
3413e519524SHoward Hinnant    is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
3423e519524SHoward Hinnant
3433e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3443e519524SHoward Hinnant    void
3453e519524SHoward Hinnant    sort(RandomAccessIterator first, RandomAccessIterator last);
3463e519524SHoward Hinnant
3473e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3483e519524SHoward Hinnant    void
3493e519524SHoward Hinnant    sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
3503e519524SHoward Hinnant
3513e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3523e519524SHoward Hinnant    void
3533e519524SHoward Hinnant    stable_sort(RandomAccessIterator first, RandomAccessIterator last);
3543e519524SHoward Hinnant
3553e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3563e519524SHoward Hinnant    void
3573e519524SHoward Hinnant    stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
3583e519524SHoward Hinnant
3593e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3603e519524SHoward Hinnant    void
3613e519524SHoward Hinnant    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
3623e519524SHoward Hinnant
3633e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3643e519524SHoward Hinnant    void
3653e519524SHoward Hinnant    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
3663e519524SHoward Hinnant
3673e519524SHoward Hinnanttemplate <class InputIterator, class RandomAccessIterator>
3683e519524SHoward Hinnant    RandomAccessIterator
3693e519524SHoward Hinnant    partial_sort_copy(InputIterator first, InputIterator last,
3703e519524SHoward Hinnant                      RandomAccessIterator result_first, RandomAccessIterator result_last);
3713e519524SHoward Hinnant
3723e519524SHoward Hinnanttemplate <class InputIterator, class RandomAccessIterator, class Compare>
3733e519524SHoward Hinnant    RandomAccessIterator
3743e519524SHoward Hinnant    partial_sort_copy(InputIterator first, InputIterator last,
3753e519524SHoward Hinnant                      RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
3763e519524SHoward Hinnant
3773e519524SHoward Hinnanttemplate <class RandomAccessIterator>
3783e519524SHoward Hinnant    void
3793e519524SHoward Hinnant    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
3803e519524SHoward Hinnant
3813e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
3823e519524SHoward Hinnant    void
3833e519524SHoward Hinnant    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
3843e519524SHoward Hinnant
3853e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
386d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3873e519524SHoward Hinnant    lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
3883e519524SHoward Hinnant
3893e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
390d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3913e519524SHoward Hinnant    lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
3923e519524SHoward Hinnant
3933e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
394d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3953e519524SHoward Hinnant    upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
3963e519524SHoward Hinnant
3973e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
398d57c03ddSMarshall Clow    constexpr ForwardIterator                         // constexpr in C++20
3993e519524SHoward Hinnant    upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4003e519524SHoward Hinnant
4013e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
402d57c03ddSMarshall Clow    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
4033e519524SHoward Hinnant    equal_range(ForwardIterator first, ForwardIterator last, const T& value);
4043e519524SHoward Hinnant
4053e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
406d57c03ddSMarshall Clow    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
4073e519524SHoward Hinnant    equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4083e519524SHoward Hinnant
4093e519524SHoward Hinnanttemplate <class ForwardIterator, class T>
410d57c03ddSMarshall Clow    constexpr bool                                    // constexpr in C++20
4113e519524SHoward Hinnant    binary_search(ForwardIterator first, ForwardIterator last, const T& value);
4123e519524SHoward Hinnant
4133e519524SHoward Hinnanttemplate <class ForwardIterator, class T, class Compare>
4148da1a487SMarshall Clow    constexpr bool                                    // constexpr in C++20
4153e519524SHoward Hinnant    binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
4163e519524SHoward Hinnant
4173e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4183e519524SHoward Hinnant    OutputIterator
4193e519524SHoward Hinnant    merge(InputIterator1 first1, InputIterator1 last1,
4203e519524SHoward Hinnant          InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4213e519524SHoward Hinnant
4223e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4233e519524SHoward Hinnant    OutputIterator
4243e519524SHoward Hinnant    merge(InputIterator1 first1, InputIterator1 last1,
4253e519524SHoward Hinnant          InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4263e519524SHoward Hinnant
4273e519524SHoward Hinnanttemplate <class BidirectionalIterator>
4283e519524SHoward Hinnant    void
4293e519524SHoward Hinnant    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
4303e519524SHoward Hinnant
4313e519524SHoward Hinnanttemplate <class BidirectionalIterator, class Compare>
4323e519524SHoward Hinnant    void
4333e519524SHoward Hinnant    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
4343e519524SHoward Hinnant
4353e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
4368da1a487SMarshall Clow    constexpr bool                                    // constexpr in C++20
4373e519524SHoward Hinnant    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
4383e519524SHoward Hinnant
4393e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class Compare>
4408da1a487SMarshall Clow    constexpr bool                                    // constexpr in C++20
4413e519524SHoward Hinnant    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
4423e519524SHoward Hinnant
4433e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4443e519524SHoward Hinnant    OutputIterator
4453e519524SHoward Hinnant    set_union(InputIterator1 first1, InputIterator1 last1,
4463e519524SHoward Hinnant              InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4473e519524SHoward Hinnant
4483e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4493e519524SHoward Hinnant    OutputIterator
4503e519524SHoward Hinnant    set_union(InputIterator1 first1, InputIterator1 last1,
4513e519524SHoward Hinnant              InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4523e519524SHoward Hinnant
4533e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4548da1a487SMarshall Clow    constexpr OutputIterator                         // constexpr in C++20
4553e519524SHoward Hinnant    set_intersection(InputIterator1 first1, InputIterator1 last1,
4563e519524SHoward Hinnant                     InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4573e519524SHoward Hinnant
4583e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4598da1a487SMarshall Clow    constexpr OutputIterator                         // constexpr in C++20
4603e519524SHoward Hinnant    set_intersection(InputIterator1 first1, InputIterator1 last1,
4613e519524SHoward Hinnant                     InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4623e519524SHoward Hinnant
4633e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4643e519524SHoward Hinnant    OutputIterator
4653e519524SHoward Hinnant    set_difference(InputIterator1 first1, InputIterator1 last1,
4663e519524SHoward Hinnant                   InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4673e519524SHoward Hinnant
4683e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4693e519524SHoward Hinnant    OutputIterator
4703e519524SHoward Hinnant    set_difference(InputIterator1 first1, InputIterator1 last1,
4713e519524SHoward Hinnant                   InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4723e519524SHoward Hinnant
4733e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator>
4743e519524SHoward Hinnant    OutputIterator
4753e519524SHoward Hinnant    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
4763e519524SHoward Hinnant                             InputIterator2 first2, InputIterator2 last2, OutputIterator result);
4773e519524SHoward Hinnant
4783e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
4793e519524SHoward Hinnant    OutputIterator
4803e519524SHoward Hinnant    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
4813e519524SHoward Hinnant                             InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
4823e519524SHoward Hinnant
4833e519524SHoward Hinnanttemplate <class RandomAccessIterator>
4843e519524SHoward Hinnant    void
4853e519524SHoward Hinnant    push_heap(RandomAccessIterator first, RandomAccessIterator last);
4863e519524SHoward Hinnant
4873e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
4883e519524SHoward Hinnant    void
4893e519524SHoward Hinnant    push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
4903e519524SHoward Hinnant
4913e519524SHoward Hinnanttemplate <class RandomAccessIterator>
4923e519524SHoward Hinnant    void
4933e519524SHoward Hinnant    pop_heap(RandomAccessIterator first, RandomAccessIterator last);
4943e519524SHoward Hinnant
4953e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
4963e519524SHoward Hinnant    void
4973e519524SHoward Hinnant    pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
4983e519524SHoward Hinnant
4993e519524SHoward Hinnanttemplate <class RandomAccessIterator>
5003e519524SHoward Hinnant    void
5013e519524SHoward Hinnant    make_heap(RandomAccessIterator first, RandomAccessIterator last);
5023e519524SHoward Hinnant
5033e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
5043e519524SHoward Hinnant    void
5053e519524SHoward Hinnant    make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
5063e519524SHoward Hinnant
5073e519524SHoward Hinnanttemplate <class RandomAccessIterator>
5083e519524SHoward Hinnant    void
5093e519524SHoward Hinnant    sort_heap(RandomAccessIterator first, RandomAccessIterator last);
5103e519524SHoward Hinnant
5113e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
5123e519524SHoward Hinnant    void
5133e519524SHoward Hinnant    sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
5143e519524SHoward Hinnant
5153e519524SHoward Hinnanttemplate <class RandomAccessIterator>
51649c7643cSMarshall Clow    constexpr bool   // constexpr in C++20
5173e519524SHoward Hinnant    is_heap(RandomAccessIterator first, RandomAccessiterator last);
5183e519524SHoward Hinnant
5193e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
52049c7643cSMarshall Clow    constexpr bool   // constexpr in C++20
5213e519524SHoward Hinnant    is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
5223e519524SHoward Hinnant
5233e519524SHoward Hinnanttemplate <class RandomAccessIterator>
52449c7643cSMarshall Clow    constexpr RandomAccessIterator   // constexpr in C++20
5253e519524SHoward Hinnant    is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
5263e519524SHoward Hinnant
5273e519524SHoward Hinnanttemplate <class RandomAccessIterator, class Compare>
52849c7643cSMarshall Clow    constexpr RandomAccessIterator   // constexpr in C++20
5293e519524SHoward Hinnant    is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
5303e519524SHoward Hinnant
5314eb27b79SHoward Hinnanttemplate <class ForwardIterator>
5324eb27b79SHoward Hinnant    ForwardIterator
5330b0671aeSMarshall Clow    min_element(ForwardIterator first, ForwardIterator last);  // constexpr in C++14
5344eb27b79SHoward Hinnant
5354eb27b79SHoward Hinnanttemplate <class ForwardIterator, class Compare>
5364eb27b79SHoward Hinnant    ForwardIterator
5370b0671aeSMarshall Clow    min_element(ForwardIterator first, ForwardIterator last, Compare comp);  // constexpr in C++14
5384eb27b79SHoward Hinnant
5393e519524SHoward Hinnanttemplate <class T>
5403e519524SHoward Hinnant    const T&
5419d67c6d5SMarshall Clow    min(const T& a, const T& b);  // constexpr in C++14
5423e519524SHoward Hinnant
5433e519524SHoward Hinnanttemplate <class T, class Compare>
5443e519524SHoward Hinnant    const T&
5459d67c6d5SMarshall Clow    min(const T& a, const T& b, Compare comp);  // constexpr in C++14
5463e519524SHoward Hinnant
5473e519524SHoward Hinnanttemplate<class T>
5484eb27b79SHoward Hinnant    T
5499d67c6d5SMarshall Clow    min(initializer_list<T> t);  // constexpr in C++14
5503e519524SHoward Hinnant
5513e519524SHoward Hinnanttemplate<class T, class Compare>
5524eb27b79SHoward Hinnant    T
5539d67c6d5SMarshall Clow    min(initializer_list<T> t, Compare comp);  // constexpr in C++14
5543e519524SHoward Hinnant
555146c14acSMarshall Clowtemplate<class T>
556146c14acSMarshall Clow    constexpr const T& clamp( const T& v, const T& lo, const T& hi );               // C++17
557146c14acSMarshall Clow
558146c14acSMarshall Clowtemplate<class T, class Compare>
559146c14acSMarshall Clow    constexpr const T& clamp( const T& v, const T& lo, const T& hi, Compare comp ); // C++17
560146c14acSMarshall Clow
5613e519524SHoward Hinnanttemplate <class ForwardIterator>
5623e519524SHoward Hinnant    ForwardIterator
5630b0671aeSMarshall Clow    max_element(ForwardIterator first, ForwardIterator last);  // constexpr in C++14
5643e519524SHoward Hinnant
5653e519524SHoward Hinnanttemplate <class ForwardIterator, class Compare>
5663e519524SHoward Hinnant    ForwardIterator
5670b0671aeSMarshall Clow    max_element(ForwardIterator first, ForwardIterator last, Compare comp);  // constexpr in C++14
5683e519524SHoward Hinnant
5694eb27b79SHoward Hinnanttemplate <class T>
5704eb27b79SHoward Hinnant    const T&
5719d67c6d5SMarshall Clow    max(const T& a, const T& b); // constexpr in C++14
5724eb27b79SHoward Hinnant
5734eb27b79SHoward Hinnanttemplate <class T, class Compare>
5744eb27b79SHoward Hinnant    const T&
5759d67c6d5SMarshall Clow    max(const T& a, const T& b, Compare comp);  // constexpr in C++14
5764eb27b79SHoward Hinnant
5774eb27b79SHoward Hinnanttemplate<class T>
5784eb27b79SHoward Hinnant    T
5799d67c6d5SMarshall Clow    max(initializer_list<T> t);  // constexpr in C++14
5804eb27b79SHoward Hinnant
5814eb27b79SHoward Hinnanttemplate<class T, class Compare>
5824eb27b79SHoward Hinnant    T
5839d67c6d5SMarshall Clow    max(initializer_list<T> t, Compare comp);  // constexpr in C++14
5844eb27b79SHoward Hinnant
5854eb27b79SHoward Hinnanttemplate<class ForwardIterator>
5864eb27b79SHoward Hinnant    pair<ForwardIterator, ForwardIterator>
5870b0671aeSMarshall Clow    minmax_element(ForwardIterator first, ForwardIterator last);   // constexpr in C++14
5884eb27b79SHoward Hinnant
5894eb27b79SHoward Hinnanttemplate<class ForwardIterator, class Compare>
5904eb27b79SHoward Hinnant    pair<ForwardIterator, ForwardIterator>
5910b0671aeSMarshall Clow    minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);   // constexpr in C++14
5924eb27b79SHoward Hinnant
5934eb27b79SHoward Hinnanttemplate<class T>
5944eb27b79SHoward Hinnant    pair<const T&, const T&>
5959d67c6d5SMarshall Clow    minmax(const T& a, const T& b);  // constexpr in C++14
5964eb27b79SHoward Hinnant
5974eb27b79SHoward Hinnanttemplate<class T, class Compare>
5984eb27b79SHoward Hinnant    pair<const T&, const T&>
5999d67c6d5SMarshall Clow    minmax(const T& a, const T& b, Compare comp);  // constexpr in C++14
6004eb27b79SHoward Hinnant
6014eb27b79SHoward Hinnanttemplate<class T>
6024eb27b79SHoward Hinnant    pair<T, T>
6039d67c6d5SMarshall Clow    minmax(initializer_list<T> t);  // constexpr in C++14
6044eb27b79SHoward Hinnant
6054eb27b79SHoward Hinnanttemplate<class T, class Compare>
6064eb27b79SHoward Hinnant    pair<T, T>
6079d67c6d5SMarshall Clow    minmax(initializer_list<T> t, Compare comp);  // constexpr in C++14
6084eb27b79SHoward Hinnant
6093e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2>
6101b9a4ffdSMarshall Clow    constexpr bool     // constexpr in C++20
6113e519524SHoward Hinnant    lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
6123e519524SHoward Hinnant
6133e519524SHoward Hinnanttemplate <class InputIterator1, class InputIterator2, class Compare>
6141b9a4ffdSMarshall Clow    constexpr bool     // constexpr in C++20
6153e519524SHoward Hinnant    lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
6163e519524SHoward Hinnant                            InputIterator2 first2, InputIterator2 last2, Compare comp);
6173e519524SHoward Hinnant
6183e519524SHoward Hinnanttemplate <class BidirectionalIterator>
6193e519524SHoward Hinnant    bool
6203e519524SHoward Hinnant    next_permutation(BidirectionalIterator first, BidirectionalIterator last);
6213e519524SHoward Hinnant
6223e519524SHoward Hinnanttemplate <class BidirectionalIterator, class Compare>
6233e519524SHoward Hinnant    bool
6243e519524SHoward Hinnant    next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
6253e519524SHoward Hinnant
6263e519524SHoward Hinnanttemplate <class BidirectionalIterator>
6273e519524SHoward Hinnant    bool
6283e519524SHoward Hinnant    prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
6293e519524SHoward Hinnant
6303e519524SHoward Hinnanttemplate <class BidirectionalIterator, class Compare>
6313e519524SHoward Hinnant    bool
6323e519524SHoward Hinnant    prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
6333e519524SHoward Hinnant
6343e519524SHoward Hinnant}  // std
6353e519524SHoward Hinnant
6363e519524SHoward Hinnant*/
6373e519524SHoward Hinnant
6383e519524SHoward Hinnant#include <__config>
6393e519524SHoward Hinnant#include <initializer_list>
6403e519524SHoward Hinnant#include <type_traits>
6413e519524SHoward Hinnant#include <cstring>
642f07dd8d0SEric Fiselier#include <utility> // needed to provide swap_ranges.
6433e519524SHoward Hinnant#include <memory>
644d835e592SMarshall Clow#include <functional>
6453e519524SHoward Hinnant#include <iterator>
646a1d07d57SHoward Hinnant#include <cstddef>
647e02ee4f0SMarshall Clow#include <bit>
648f56972e2SMarshall Clow#include <version>
6495d1a701dSHoward Hinnant
650c1bd9197SEric Fiselier#include <__debug>
651c1bd9197SEric Fiselier
652073458b1SHoward Hinnant#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
6533e519524SHoward Hinnant#pragma GCC system_header
654073458b1SHoward Hinnant#endif
6553e519524SHoward Hinnant
656a016efb1SEric Fiselier_LIBCPP_PUSH_MACROS
657a016efb1SEric Fiselier#include <__undef_macros>
658a016efb1SEric Fiselier
659a016efb1SEric Fiselier
6603e519524SHoward Hinnant_LIBCPP_BEGIN_NAMESPACE_STD
6613e519524SHoward Hinnant
6629d67c6d5SMarshall Clow// I'd like to replace these with _VSTD::equal_to<void>, but can't because:
6639d67c6d5SMarshall Clow//   * That only works with C++14 and later, and
6649d67c6d5SMarshall Clow//   * We haven't included <functional> here.
6653e519524SHoward Hinnanttemplate <class _T1, class _T2 = _T1>
6663e519524SHoward Hinnantstruct __equal_to
6673e519524SHoward Hinnant{
668d8098f97SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
669d8098f97SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T2& __y) const {return __x == __y;}
670d8098f97SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T1& __y) const {return __x == __y;}
671d8098f97SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T2& __y) const {return __x == __y;}
6723e519524SHoward Hinnant};
6733e519524SHoward Hinnant
6743e519524SHoward Hinnanttemplate <class _T1>
6753e519524SHoward Hinnantstruct __equal_to<_T1, _T1>
6763e519524SHoward Hinnant{
6779d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6789d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6793e519524SHoward Hinnant};
6803e519524SHoward Hinnant
6813e519524SHoward Hinnanttemplate <class _T1>
6823e519524SHoward Hinnantstruct __equal_to<const _T1, _T1>
6833e519524SHoward Hinnant{
6849d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6859d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6863e519524SHoward Hinnant};
6873e519524SHoward Hinnant
6883e519524SHoward Hinnanttemplate <class _T1>
6893e519524SHoward Hinnantstruct __equal_to<_T1, const _T1>
6903e519524SHoward Hinnant{
6919d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6929d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
6933e519524SHoward Hinnant};
6943e519524SHoward Hinnant
6953e519524SHoward Hinnanttemplate <class _T1, class _T2 = _T1>
6963e519524SHoward Hinnantstruct __less
6973e519524SHoward Hinnant{
6989d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
6999d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7009d67c6d5SMarshall Clow
7019d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7029d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T2& __y) const {return __x < __y;}
7039d67c6d5SMarshall Clow
7049d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7059d67c6d5SMarshall Clow    bool operator()(const _T2& __x, const _T1& __y) const {return __x < __y;}
7069d67c6d5SMarshall Clow
7079d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7089d67c6d5SMarshall Clow    bool operator()(const _T2& __x, const _T2& __y) const {return __x < __y;}
7093e519524SHoward Hinnant};
7103e519524SHoward Hinnant
7113e519524SHoward Hinnanttemplate <class _T1>
7123e519524SHoward Hinnantstruct __less<_T1, _T1>
7133e519524SHoward Hinnant{
7149d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7159d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7163e519524SHoward Hinnant};
7173e519524SHoward Hinnant
7183e519524SHoward Hinnanttemplate <class _T1>
7193e519524SHoward Hinnantstruct __less<const _T1, _T1>
7203e519524SHoward Hinnant{
7219d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7229d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7233e519524SHoward Hinnant};
7243e519524SHoward Hinnant
7253e519524SHoward Hinnanttemplate <class _T1>
7263e519524SHoward Hinnantstruct __less<_T1, const _T1>
7273e519524SHoward Hinnant{
7289d67c6d5SMarshall Clow    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
7299d67c6d5SMarshall Clow    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
7303e519524SHoward Hinnant};
7313e519524SHoward Hinnant
7323e519524SHoward Hinnanttemplate <class _Predicate>
733a763b36fSMarshall Clowclass __invert // invert the sense of a comparison
7343e519524SHoward Hinnant{
7353e519524SHoward Hinnantprivate:
7363e519524SHoward Hinnant    _Predicate __p_;
7373e519524SHoward Hinnantpublic:
738a763b36fSMarshall Clow    _LIBCPP_INLINE_VISIBILITY __invert() {}
7393e519524SHoward Hinnant
7403e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
741a763b36fSMarshall Clow    explicit __invert(_Predicate __p) : __p_(__p) {}
7423e519524SHoward Hinnant
7433e519524SHoward Hinnant    template <class _T1>
7443e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
7453e519524SHoward Hinnant    bool operator()(const _T1& __x) {return !__p_(__x);}
7463e519524SHoward Hinnant
7473e519524SHoward Hinnant    template <class _T1, class _T2>
7483e519524SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY
749a763b36fSMarshall Clow    bool operator()(const _T1& __x, const _T2& __y) {return __p_(__y, __x);}
7503e519524SHoward Hinnant};
7513e519524SHoward Hinnant
75204695a75SLouis Dionne// Perform division by two quickly for positive integers (llvm.org/PR39129)
75304695a75SLouis Dionne
75404695a75SLouis Dionnetemplate <typename _Integral>
75504695a75SLouis Dionne_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
75604695a75SLouis Dionnetypename enable_if
75704695a75SLouis Dionne<
75804695a75SLouis Dionne    is_integral<_Integral>::value,
75904695a75SLouis Dionne    _Integral
76004695a75SLouis Dionne>::type
76104695a75SLouis Dionne__half_positive(_Integral __value)
76204695a75SLouis Dionne{
76304695a75SLouis Dionne    return static_cast<_Integral>(static_cast<typename make_unsigned<_Integral>::type>(__value) / 2);
76404695a75SLouis Dionne}
76504695a75SLouis Dionne
76604695a75SLouis Dionnetemplate <typename _Tp>
76704695a75SLouis Dionne_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
76804695a75SLouis Dionnetypename enable_if
76904695a75SLouis Dionne<
77004695a75SLouis Dionne    !is_integral<_Tp>::value,
77104695a75SLouis Dionne    _Tp
77204695a75SLouis Dionne>::type
77304695a75SLouis Dionne__half_positive(_Tp __value)
77404695a75SLouis Dionne{
77504695a75SLouis Dionne    return __value / 2;
77604695a75SLouis Dionne}
77704695a75SLouis Dionne
778145afa17SHoward Hinnant#ifdef _LIBCPP_DEBUG
7793e519524SHoward Hinnant
7803e519524SHoward Hinnanttemplate <class _Compare>
7813e519524SHoward Hinnantstruct __debug_less
7823e519524SHoward Hinnant{
783aa1cad15SEric Fiselier    _Compare &__comp_;
784aa1cad15SEric Fiselier    _LIBCPP_CONSTEXPR_AFTER_CXX17
7853e519524SHoward Hinnant    __debug_less(_Compare& __c) : __comp_(__c) {}
786331d2159SEric Fiselier
7873e519524SHoward Hinnant    template <class _Tp, class _Up>
7886ab51de0SThomas Anderson    _LIBCPP_CONSTEXPR_AFTER_CXX17
7893c3ccc00SThomas Anderson    bool operator()(const _Tp& __x,  const _Up& __y)
7903c3ccc00SThomas Anderson    {
7913c3ccc00SThomas Anderson        bool __r = __comp_(__x, __y);
7923c3ccc00SThomas Anderson        if (__r)
7933c3ccc00SThomas Anderson            __do_compare_assert(0, __y, __x);
7943c3ccc00SThomas Anderson        return __r;
7953c3ccc00SThomas Anderson    }
7963c3ccc00SThomas Anderson
7973c3ccc00SThomas Anderson    template <class _Tp, class _Up>
798aa1cad15SEric Fiselier    _LIBCPP_CONSTEXPR_AFTER_CXX17
7996e4ec602SEric Fiselier    bool operator()(_Tp& __x,  _Up& __y)
8003e519524SHoward Hinnant    {
8013e519524SHoward Hinnant        bool __r = __comp_(__x, __y);
8023e519524SHoward Hinnant        if (__r)
803331d2159SEric Fiselier            __do_compare_assert(0, __y, __x);
8043e519524SHoward Hinnant        return __r;
8053e519524SHoward Hinnant    }
806331d2159SEric Fiselier
807331d2159SEric Fiselier    template <class _LHS, class _RHS>
808aa1cad15SEric Fiselier    _LIBCPP_CONSTEXPR_AFTER_CXX17
809331d2159SEric Fiselier    inline _LIBCPP_INLINE_VISIBILITY
810331d2159SEric Fiselier    decltype((void)_VSTD::declval<_Compare&>()(
8116e4ec602SEric Fiselier        _VSTD::declval<_LHS &>(), _VSTD::declval<_RHS &>()))
8126e4ec602SEric Fiselier    __do_compare_assert(int, _LHS & __l, _RHS & __r) {
813331d2159SEric Fiselier        _LIBCPP_ASSERT(!__comp_(__l, __r),
814331d2159SEric Fiselier            "Comparator does not induce a strict weak ordering");
815331d2159SEric Fiselier    }
816331d2159SEric Fiselier
817331d2159SEric Fiselier    template <class _LHS, class _RHS>
818aa1cad15SEric Fiselier    _LIBCPP_CONSTEXPR_AFTER_CXX17
819331d2159SEric Fiselier    inline _LIBCPP_INLINE_VISIBILITY
8206e4ec602SEric Fiselier    void __do_compare_assert(long, _LHS &, _RHS &) {}
8213e519524SHoward Hinnant};
8223e519524SHoward Hinnant
823145afa17SHoward Hinnant#endif // _LIBCPP_DEBUG
8243e519524SHoward Hinnant
825aa1cad15SEric Fiseliertemplate <class _Comp>
826aa1cad15SEric Fiselierstruct __comp_ref_type {
827aa1cad15SEric Fiselier  // Pass the comparator by lvalue reference. Or in debug mode, using a
828aa1cad15SEric Fiselier  // debugging wrapper that stores a reference.
829aa1cad15SEric Fiselier#ifndef _LIBCPP_DEBUG
830aa1cad15SEric Fiselier  typedef typename add_lvalue_reference<_Comp>::type type;
831aa1cad15SEric Fiselier#else
832aa1cad15SEric Fiselier  typedef __debug_less<_Comp> type;
833aa1cad15SEric Fiselier#endif
834aa1cad15SEric Fiselier};
835aa1cad15SEric Fiselier
8363e519524SHoward Hinnant// all_of
8373e519524SHoward Hinnant
8383e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
8391362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
8401362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8413e519524SHoward Hinnantbool
8423e519524SHoward Hinnantall_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
8433e519524SHoward Hinnant{
8443e519524SHoward Hinnant    for (; __first != __last; ++__first)
8453e519524SHoward Hinnant        if (!__pred(*__first))
8463e519524SHoward Hinnant            return false;
8473e519524SHoward Hinnant    return true;
8483e519524SHoward Hinnant}
8493e519524SHoward Hinnant
8503e519524SHoward Hinnant// any_of
8513e519524SHoward Hinnant
8523e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
8531362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
8541362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8553e519524SHoward Hinnantbool
8563e519524SHoward Hinnantany_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
8573e519524SHoward Hinnant{
8583e519524SHoward Hinnant    for (; __first != __last; ++__first)
8593e519524SHoward Hinnant        if (__pred(*__first))
8603e519524SHoward Hinnant            return true;
8613e519524SHoward Hinnant    return false;
8623e519524SHoward Hinnant}
8633e519524SHoward Hinnant
8643e519524SHoward Hinnant// none_of
8653e519524SHoward Hinnant
8663e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
8671362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
8681362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8693e519524SHoward Hinnantbool
8703e519524SHoward Hinnantnone_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
8713e519524SHoward Hinnant{
8723e519524SHoward Hinnant    for (; __first != __last; ++__first)
8733e519524SHoward Hinnant        if (__pred(*__first))
8743e519524SHoward Hinnant            return false;
8753e519524SHoward Hinnant    return true;
8763e519524SHoward Hinnant}
8773e519524SHoward Hinnant
8783e519524SHoward Hinnant// for_each
8793e519524SHoward Hinnant
8803e519524SHoward Hinnanttemplate <class _InputIterator, class _Function>
8811b9a4ffdSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
8823e519524SHoward Hinnant_Function
8833e519524SHoward Hinnantfor_each(_InputIterator __first, _InputIterator __last, _Function __f)
8843e519524SHoward Hinnant{
8853e519524SHoward Hinnant    for (; __first != __last; ++__first)
8863e519524SHoward Hinnant        __f(*__first);
8871c7fe126SMarshall Clow    return __f;
8883e519524SHoward Hinnant}
8893e519524SHoward Hinnant
8901d02996dSMarshall Clow#if _LIBCPP_STD_VER > 14
891d5c65ffaSMarshall Clow// for_each_n
892d5c65ffaSMarshall Clow
893d5c65ffaSMarshall Clowtemplate <class _InputIterator, class _Size, class _Function>
8941b9a4ffdSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
895d5c65ffaSMarshall Clow_InputIterator
896d5c65ffaSMarshall Clowfor_each_n(_InputIterator __first, _Size __orig_n, _Function __f)
897d5c65ffaSMarshall Clow{
898d5c65ffaSMarshall Clow    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
899d5c65ffaSMarshall Clow    _IntegralSize __n = __orig_n;
900d5c65ffaSMarshall Clow    while (__n > 0)
901d5c65ffaSMarshall Clow    {
902d5c65ffaSMarshall Clow         __f(*__first);
903d5c65ffaSMarshall Clow         ++__first;
904d5c65ffaSMarshall Clow         --__n;
905d5c65ffaSMarshall Clow    }
906d5c65ffaSMarshall Clow    return __first;
907d5c65ffaSMarshall Clow}
9081d02996dSMarshall Clow#endif
909d5c65ffaSMarshall Clow
9103e519524SHoward Hinnant// find
9113e519524SHoward Hinnant
9123e519524SHoward Hinnanttemplate <class _InputIterator, class _Tp>
9131362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
9141362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9153e519524SHoward Hinnant_InputIterator
916e4383379SHoward Hinnantfind(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
9173e519524SHoward Hinnant{
9183e519524SHoward Hinnant    for (; __first != __last; ++__first)
919e4383379SHoward Hinnant        if (*__first == __value_)
9203e519524SHoward Hinnant            break;
9213e519524SHoward Hinnant    return __first;
9223e519524SHoward Hinnant}
9233e519524SHoward Hinnant
9243e519524SHoward Hinnant// find_if
9253e519524SHoward Hinnant
9263e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
9271362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
9281362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9293e519524SHoward Hinnant_InputIterator
9303e519524SHoward Hinnantfind_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9313e519524SHoward Hinnant{
9323e519524SHoward Hinnant    for (; __first != __last; ++__first)
9333e519524SHoward Hinnant        if (__pred(*__first))
9343e519524SHoward Hinnant            break;
9353e519524SHoward Hinnant    return __first;
9363e519524SHoward Hinnant}
9373e519524SHoward Hinnant
9383e519524SHoward Hinnant// find_if_not
9393e519524SHoward Hinnant
9403e519524SHoward Hinnanttemplate<class _InputIterator, class _Predicate>
9411362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
9421362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
9433e519524SHoward Hinnant_InputIterator
9443e519524SHoward Hinnantfind_if_not(_InputIterator __first, _InputIterator __last, _Predicate __pred)
9453e519524SHoward Hinnant{
9463e519524SHoward Hinnant    for (; __first != __last; ++__first)
9473e519524SHoward Hinnant        if (!__pred(*__first))
9483e519524SHoward Hinnant            break;
9493e519524SHoward Hinnant    return __first;
9503e519524SHoward Hinnant}
9513e519524SHoward Hinnant
9523e519524SHoward Hinnant// find_end
9533e519524SHoward Hinnant
9543e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
9558694428eSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
9563e519524SHoward Hinnant__find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
9573e519524SHoward Hinnant           _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
9583e519524SHoward Hinnant           forward_iterator_tag, forward_iterator_tag)
9593e519524SHoward Hinnant{
9603e519524SHoward Hinnant    // modeled after search algorithm
9613e519524SHoward Hinnant    _ForwardIterator1 __r = __last1;  // __last1 is the "default" answer
9623e519524SHoward Hinnant    if (__first2 == __last2)
9633e519524SHoward Hinnant        return __r;
9643e519524SHoward Hinnant    while (true)
9653e519524SHoward Hinnant    {
9663e519524SHoward Hinnant        while (true)
9673e519524SHoward Hinnant        {
9683e519524SHoward Hinnant            if (__first1 == __last1)         // if source exhausted return last correct answer
9693e519524SHoward Hinnant                return __r;                  //    (or __last1 if never found)
9703e519524SHoward Hinnant            if (__pred(*__first1, *__first2))
9713e519524SHoward Hinnant                break;
9723e519524SHoward Hinnant            ++__first1;
9733e519524SHoward Hinnant        }
9743e519524SHoward Hinnant        // *__first1 matches *__first2, now match elements after here
9753e519524SHoward Hinnant        _ForwardIterator1 __m1 = __first1;
9763e519524SHoward Hinnant        _ForwardIterator2 __m2 = __first2;
9773e519524SHoward Hinnant        while (true)
9783e519524SHoward Hinnant        {
9793e519524SHoward Hinnant            if (++__m2 == __last2)
9803e519524SHoward Hinnant            {                         // Pattern exhaused, record answer and search for another one
9813e519524SHoward Hinnant                __r = __first1;
9823e519524SHoward Hinnant                ++__first1;
9833e519524SHoward Hinnant                break;
9843e519524SHoward Hinnant            }
9853e519524SHoward Hinnant            if (++__m1 == __last1)     // Source exhausted, return last answer
9863e519524SHoward Hinnant                return __r;
9873e519524SHoward Hinnant            if (!__pred(*__m1, *__m2))  // mismatch, restart with a new __first
9883e519524SHoward Hinnant            {
9893e519524SHoward Hinnant                ++__first1;
9903e519524SHoward Hinnant                break;
9913e519524SHoward Hinnant            }  // else there is a match, check next elements
9923e519524SHoward Hinnant        }
9933e519524SHoward Hinnant    }
9943e519524SHoward Hinnant}
9953e519524SHoward Hinnant
9963e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _BidirectionalIterator1, class _BidirectionalIterator2>
9978694428eSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator1
9983e519524SHoward Hinnant__find_end(_BidirectionalIterator1 __first1, _BidirectionalIterator1 __last1,
9993e519524SHoward Hinnant           _BidirectionalIterator2 __first2, _BidirectionalIterator2 __last2, _BinaryPredicate __pred,
10003e519524SHoward Hinnant           bidirectional_iterator_tag, bidirectional_iterator_tag)
10013e519524SHoward Hinnant{
10023e519524SHoward Hinnant    // modeled after search algorithm (in reverse)
10033e519524SHoward Hinnant    if (__first2 == __last2)
10043e519524SHoward Hinnant        return __last1;  // Everything matches an empty sequence
10053e519524SHoward Hinnant    _BidirectionalIterator1 __l1 = __last1;
10063e519524SHoward Hinnant    _BidirectionalIterator2 __l2 = __last2;
10073e519524SHoward Hinnant    --__l2;
10083e519524SHoward Hinnant    while (true)
10093e519524SHoward Hinnant    {
10103e519524SHoward Hinnant        // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
10113e519524SHoward Hinnant        while (true)
10123e519524SHoward Hinnant        {
10133e519524SHoward Hinnant            if (__first1 == __l1)  // return __last1 if no element matches *__first2
10143e519524SHoward Hinnant                return __last1;
10153e519524SHoward Hinnant            if (__pred(*--__l1, *__l2))
10163e519524SHoward Hinnant                break;
10173e519524SHoward Hinnant        }
10183e519524SHoward Hinnant        // *__l1 matches *__l2, now match elements before here
10193e519524SHoward Hinnant        _BidirectionalIterator1 __m1 = __l1;
10203e519524SHoward Hinnant        _BidirectionalIterator2 __m2 = __l2;
10213e519524SHoward Hinnant        while (true)
10223e519524SHoward Hinnant        {
10233e519524SHoward Hinnant            if (__m2 == __first2)  // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
10243e519524SHoward Hinnant                return __m1;
10253e519524SHoward Hinnant            if (__m1 == __first1)  // Otherwise if source exhaused, pattern not found
10263e519524SHoward Hinnant                return __last1;
10273e519524SHoward Hinnant            if (!__pred(*--__m1, *--__m2))  // if there is a mismatch, restart with a new __l1
10283e519524SHoward Hinnant            {
10293e519524SHoward Hinnant                break;
10303e519524SHoward Hinnant            }  // else there is a match, check next elements
10313e519524SHoward Hinnant        }
10323e519524SHoward Hinnant    }
10333e519524SHoward Hinnant}
10343e519524SHoward Hinnant
10353e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
10369b0af34dSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1
10373e519524SHoward Hinnant__find_end(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
10383e519524SHoward Hinnant           _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
10393e519524SHoward Hinnant           random_access_iterator_tag, random_access_iterator_tag)
10403e519524SHoward Hinnant{
10413e519524SHoward Hinnant    // Take advantage of knowing source and pattern lengths.  Stop short when source is smaller than pattern
10423e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator2>::difference_type __len2 = __last2 - __first2;
10433e519524SHoward Hinnant    if (__len2 == 0)
10443e519524SHoward Hinnant        return __last1;
10453e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator1>::difference_type __len1 = __last1 - __first1;
10463e519524SHoward Hinnant    if (__len1 < __len2)
10473e519524SHoward Hinnant        return __last1;
10483e519524SHoward Hinnant    const _RandomAccessIterator1 __s = __first1 + (__len2 - 1);  // End of pattern match can't go before here
10493e519524SHoward Hinnant    _RandomAccessIterator1 __l1 = __last1;
10503e519524SHoward Hinnant    _RandomAccessIterator2 __l2 = __last2;
10513e519524SHoward Hinnant    --__l2;
10523e519524SHoward Hinnant    while (true)
10533e519524SHoward Hinnant    {
10543e519524SHoward Hinnant        while (true)
10553e519524SHoward Hinnant        {
10563e519524SHoward Hinnant            if (__s == __l1)
10573e519524SHoward Hinnant                return __last1;
10583e519524SHoward Hinnant            if (__pred(*--__l1, *__l2))
10593e519524SHoward Hinnant                break;
10603e519524SHoward Hinnant        }
10613e519524SHoward Hinnant        _RandomAccessIterator1 __m1 = __l1;
10623e519524SHoward Hinnant        _RandomAccessIterator2 __m2 = __l2;
10633e519524SHoward Hinnant        while (true)
10643e519524SHoward Hinnant        {
10653e519524SHoward Hinnant            if (__m2 == __first2)
10663e519524SHoward Hinnant                return __m1;
10673e519524SHoward Hinnant                                 // no need to check range on __m1 because __s guarantees we have enough source
10683e519524SHoward Hinnant            if (!__pred(*--__m1, *--__m2))
10693e519524SHoward Hinnant            {
10703e519524SHoward Hinnant                break;
10713e519524SHoward Hinnant            }
10723e519524SHoward Hinnant        }
10733e519524SHoward Hinnant    }
10743e519524SHoward Hinnant}
10753e519524SHoward Hinnant
10763e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
10771362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
10781362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
10793e519524SHoward Hinnant_ForwardIterator1
10803e519524SHoward Hinnantfind_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
10813e519524SHoward Hinnant         _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
10823e519524SHoward Hinnant{
1083ce48a113SHoward Hinnant    return _VSTD::__find_end<typename add_lvalue_reference<_BinaryPredicate>::type>
10843e519524SHoward Hinnant                         (__first1, __last1, __first2, __last2, __pred,
10853e519524SHoward Hinnant                          typename iterator_traits<_ForwardIterator1>::iterator_category(),
10863e519524SHoward Hinnant                          typename iterator_traits<_ForwardIterator2>::iterator_category());
10873e519524SHoward Hinnant}
10883e519524SHoward Hinnant
10893e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2>
10901362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
10911362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
10923e519524SHoward Hinnant_ForwardIterator1
10933e519524SHoward Hinnantfind_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
10943e519524SHoward Hinnant         _ForwardIterator2 __first2, _ForwardIterator2 __last2)
10953e519524SHoward Hinnant{
10963e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
10973e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1098ce48a113SHoward Hinnant    return _VSTD::find_end(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
10993e519524SHoward Hinnant}
11003e519524SHoward Hinnant
11013e519524SHoward Hinnant// find_first_of
11023e519524SHoward Hinnant
11033e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11049b0af34dSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator1
11059b0af34dSMarshall Clow__find_first_of_ce(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11063e519524SHoward Hinnant              _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11073e519524SHoward Hinnant{
11083e519524SHoward Hinnant    for (; __first1 != __last1; ++__first1)
11093e519524SHoward Hinnant        for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
11103e519524SHoward Hinnant            if (__pred(*__first1, *__j))
11113e519524SHoward Hinnant                return __first1;
11123e519524SHoward Hinnant    return __last1;
11133e519524SHoward Hinnant}
11143e519524SHoward Hinnant
11159b0af34dSMarshall Clow
11169b0af34dSMarshall Clowtemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
11171362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
11181362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11199b0af34dSMarshall Clow_ForwardIterator1
11209b0af34dSMarshall Clowfind_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11219b0af34dSMarshall Clow              _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
11229b0af34dSMarshall Clow{
11239b0af34dSMarshall Clow    return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __pred);
11249b0af34dSMarshall Clow}
11259b0af34dSMarshall Clow
11263e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2>
11271362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
11281362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11293e519524SHoward Hinnant_ForwardIterator1
11303e519524SHoward Hinnantfind_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
11313e519524SHoward Hinnant              _ForwardIterator2 __first2, _ForwardIterator2 __last2)
11323e519524SHoward Hinnant{
11333e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
11343e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
11359b0af34dSMarshall Clow    return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
11363e519524SHoward Hinnant}
11373e519524SHoward Hinnant
11383e519524SHoward Hinnant// adjacent_find
11393e519524SHoward Hinnant
11403e519524SHoward Hinnanttemplate <class _ForwardIterator, class _BinaryPredicate>
11411362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
11421362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11433e519524SHoward Hinnant_ForwardIterator
11443e519524SHoward Hinnantadjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
11453e519524SHoward Hinnant{
11463e519524SHoward Hinnant    if (__first != __last)
11473e519524SHoward Hinnant    {
11483e519524SHoward Hinnant        _ForwardIterator __i = __first;
11493e519524SHoward Hinnant        while (++__i != __last)
11503e519524SHoward Hinnant        {
11513e519524SHoward Hinnant            if (__pred(*__first, *__i))
11523e519524SHoward Hinnant                return __first;
11533e519524SHoward Hinnant            __first = __i;
11543e519524SHoward Hinnant        }
11553e519524SHoward Hinnant    }
11563e519524SHoward Hinnant    return __last;
11573e519524SHoward Hinnant}
11583e519524SHoward Hinnant
11593e519524SHoward Hinnanttemplate <class _ForwardIterator>
11601362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
11611362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11623e519524SHoward Hinnant_ForwardIterator
11633e519524SHoward Hinnantadjacent_find(_ForwardIterator __first, _ForwardIterator __last)
11643e519524SHoward Hinnant{
11653e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
1166ce48a113SHoward Hinnant    return _VSTD::adjacent_find(__first, __last, __equal_to<__v>());
11673e519524SHoward Hinnant}
11683e519524SHoward Hinnant
11693e519524SHoward Hinnant// count
11703e519524SHoward Hinnant
11713e519524SHoward Hinnanttemplate <class _InputIterator, class _Tp>
11721362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
11731362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11743e519524SHoward Hinnanttypename iterator_traits<_InputIterator>::difference_type
1175e4383379SHoward Hinnantcount(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
11763e519524SHoward Hinnant{
11773e519524SHoward Hinnant    typename iterator_traits<_InputIterator>::difference_type __r(0);
11783e519524SHoward Hinnant    for (; __first != __last; ++__first)
1179e4383379SHoward Hinnant        if (*__first == __value_)
11803e519524SHoward Hinnant            ++__r;
11813e519524SHoward Hinnant    return __r;
11823e519524SHoward Hinnant}
11833e519524SHoward Hinnant
11843e519524SHoward Hinnant// count_if
11853e519524SHoward Hinnant
11863e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
11871362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
11881362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
11893e519524SHoward Hinnanttypename iterator_traits<_InputIterator>::difference_type
11903e519524SHoward Hinnantcount_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
11913e519524SHoward Hinnant{
11923e519524SHoward Hinnant    typename iterator_traits<_InputIterator>::difference_type __r(0);
11933e519524SHoward Hinnant    for (; __first != __last; ++__first)
11943e519524SHoward Hinnant        if (__pred(*__first))
11953e519524SHoward Hinnant            ++__r;
11963e519524SHoward Hinnant    return __r;
11973e519524SHoward Hinnant}
11983e519524SHoward Hinnant
11993e519524SHoward Hinnant// mismatch
12003e519524SHoward Hinnant
12013e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12021362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
12031362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12043e519524SHoward Hinnantpair<_InputIterator1, _InputIterator2>
12053e519524SHoward Hinnantmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12063e519524SHoward Hinnant         _InputIterator2 __first2, _BinaryPredicate __pred)
12073e519524SHoward Hinnant{
1208bd7c7b55SMarshall Clow    for (; __first1 != __last1; ++__first1, (void) ++__first2)
12093e519524SHoward Hinnant        if (!__pred(*__first1, *__first2))
12103e519524SHoward Hinnant            break;
12113e519524SHoward Hinnant    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
12123e519524SHoward Hinnant}
12133e519524SHoward Hinnant
12143e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
12151362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
12161362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12173e519524SHoward Hinnantpair<_InputIterator1, _InputIterator2>
12183e519524SHoward Hinnantmismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
12193e519524SHoward Hinnant{
12203e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12213e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1222ce48a113SHoward Hinnant    return _VSTD::mismatch(__first1, __last1, __first2, __equal_to<__v1, __v2>());
12233e519524SHoward Hinnant}
12243e519524SHoward Hinnant
12250b0bbd2fSMarshall Clow#if _LIBCPP_STD_VER > 11
12260b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12271362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
12281362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12290b0bbd2fSMarshall Clowpair<_InputIterator1, _InputIterator2>
12300b0bbd2fSMarshall Clowmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12310b0bbd2fSMarshall Clow         _InputIterator2 __first2, _InputIterator2 __last2,
12320b0bbd2fSMarshall Clow         _BinaryPredicate __pred)
12330b0bbd2fSMarshall Clow{
1234bd7c7b55SMarshall Clow    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
12350b0bbd2fSMarshall Clow        if (!__pred(*__first1, *__first2))
12360b0bbd2fSMarshall Clow            break;
12370b0bbd2fSMarshall Clow    return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
12380b0bbd2fSMarshall Clow}
12390b0bbd2fSMarshall Clow
12400b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2>
12411362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
12421362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12430b0bbd2fSMarshall Clowpair<_InputIterator1, _InputIterator2>
12440b0bbd2fSMarshall Clowmismatch(_InputIterator1 __first1, _InputIterator1 __last1,
12450b0bbd2fSMarshall Clow         _InputIterator2 __first2, _InputIterator2 __last2)
12460b0bbd2fSMarshall Clow{
12470b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12480b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
12490b0bbd2fSMarshall Clow    return _VSTD::mismatch(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
12500b0bbd2fSMarshall Clow}
12510b0bbd2fSMarshall Clow#endif
12520b0bbd2fSMarshall Clow
12533e519524SHoward Hinnant// equal
12543e519524SHoward Hinnant
12553e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
12561362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
12571362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12583e519524SHoward Hinnantbool
12593e519524SHoward Hinnantequal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred)
12603e519524SHoward Hinnant{
1261910285b2SEric Fiselier    for (; __first1 != __last1; ++__first1, (void) ++__first2)
12623e519524SHoward Hinnant        if (!__pred(*__first1, *__first2))
12633e519524SHoward Hinnant            return false;
12643e519524SHoward Hinnant    return true;
12653e519524SHoward Hinnant}
12663e519524SHoward Hinnant
12673e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
12681362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
12691362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12703e519524SHoward Hinnantbool
12713e519524SHoward Hinnantequal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
12723e519524SHoward Hinnant{
12733e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
12743e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
1275ce48a113SHoward Hinnant    return _VSTD::equal(__first1, __last1, __first2, __equal_to<__v1, __v2>());
12763e519524SHoward Hinnant}
12773e519524SHoward Hinnant
12780b0bbd2fSMarshall Clow#if _LIBCPP_STD_VER > 11
12790b0bbd2fSMarshall Clowtemplate <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
12806538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12810b0bbd2fSMarshall Clowbool
12820b0bbd2fSMarshall Clow__equal(_InputIterator1 __first1, _InputIterator1 __last1,
12830b0bbd2fSMarshall Clow        _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred,
12840b0bbd2fSMarshall Clow        input_iterator_tag, input_iterator_tag )
12850b0bbd2fSMarshall Clow{
1286910285b2SEric Fiselier    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
12870b0bbd2fSMarshall Clow        if (!__pred(*__first1, *__first2))
12880b0bbd2fSMarshall Clow            return false;
12890b0bbd2fSMarshall Clow    return __first1 == __last1 && __first2 == __last2;
12900b0bbd2fSMarshall Clow}
12910b0bbd2fSMarshall Clow
12920b0bbd2fSMarshall Clowtemplate <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
12936538e28dSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
12940b0bbd2fSMarshall Clowbool
12950b0bbd2fSMarshall Clow__equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
12960b0bbd2fSMarshall Clow        _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
12970b0bbd2fSMarshall Clow      random_access_iterator_tag, random_access_iterator_tag )
12980b0bbd2fSMarshall Clow{
12990b0bbd2fSMarshall Clow    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
13000b0bbd2fSMarshall Clow        return false;
13010b0bbd2fSMarshall Clow    return _VSTD::equal<_RandomAccessIterator1, _RandomAccessIterator2,
13020b0bbd2fSMarshall Clow                        typename add_lvalue_reference<_BinaryPredicate>::type>
13030b0bbd2fSMarshall Clow                       (__first1, __last1, __first2, __pred );
13040b0bbd2fSMarshall Clow}
13050b0bbd2fSMarshall Clow
13060b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
13071362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
13081362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13090b0bbd2fSMarshall Clowbool
13100b0bbd2fSMarshall Clowequal(_InputIterator1 __first1, _InputIterator1 __last1,
13110b0bbd2fSMarshall Clow      _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred )
13120b0bbd2fSMarshall Clow{
13130b0bbd2fSMarshall Clow    return _VSTD::__equal<typename add_lvalue_reference<_BinaryPredicate>::type>
13140b0bbd2fSMarshall Clow       (__first1, __last1, __first2, __last2, __pred,
13150b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator1>::iterator_category(),
13160b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator2>::iterator_category());
13170b0bbd2fSMarshall Clow}
13180b0bbd2fSMarshall Clow
13190b0bbd2fSMarshall Clowtemplate <class _InputIterator1, class _InputIterator2>
13201362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
13211362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13220b0bbd2fSMarshall Clowbool
13230b0bbd2fSMarshall Clowequal(_InputIterator1 __first1, _InputIterator1 __last1,
13240b0bbd2fSMarshall Clow      _InputIterator2 __first2, _InputIterator2 __last2)
13250b0bbd2fSMarshall Clow{
13260b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
13270b0bbd2fSMarshall Clow    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
13280b0bbd2fSMarshall Clow    return _VSTD::__equal(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>(),
13290b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator1>::iterator_category(),
13300b0bbd2fSMarshall Clow        typename iterator_traits<_InputIterator2>::iterator_category());
13310b0bbd2fSMarshall Clow}
13320b0bbd2fSMarshall Clow#endif
13330b0bbd2fSMarshall Clow
13343e519524SHoward Hinnant// is_permutation
13353e519524SHoward Hinnant
13363e519524SHoward Hinnanttemplate<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
13371362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
13383e519524SHoward Hinnantis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
13393e519524SHoward Hinnant               _ForwardIterator2 __first2, _BinaryPredicate __pred)
13403e519524SHoward Hinnant{
134149c7643cSMarshall Clow//  shorten sequences as much as possible by lopping of any equal prefix
1342910285b2SEric Fiselier    for (; __first1 != __last1; ++__first1, (void) ++__first2)
13433e519524SHoward Hinnant        if (!__pred(*__first1, *__first2))
134449c7643cSMarshall Clow            break;
134549c7643cSMarshall Clow    if (__first1 == __last1)
13463e519524SHoward Hinnant        return true;
134749c7643cSMarshall Clow
13483e519524SHoward Hinnant//  __first1 != __last1 && *__first1 != *__first2
13493e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
1350ce48a113SHoward Hinnant    _D1 __l1 = _VSTD::distance(__first1, __last1);
13513e519524SHoward Hinnant    if (__l1 == _D1(1))
13523e519524SHoward Hinnant        return false;
1353ce48a113SHoward Hinnant    _ForwardIterator2 __last2 = _VSTD::next(__first2, __l1);
13543e519524SHoward Hinnant    // For each element in [f1, l1) see if there are the same number of
13553e519524SHoward Hinnant    //    equal elements in [f2, l2)
13563e519524SHoward Hinnant    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
13573e519524SHoward Hinnant    {
13583e519524SHoward Hinnant    //  Have we already counted the number of *__i in [f1, l1)?
1359939b1623SPeter Collingbourne        _ForwardIterator1 __match = __first1;
1360939b1623SPeter Collingbourne        for (; __match != __i; ++__match)
1361939b1623SPeter Collingbourne            if (__pred(*__match, *__i))
1362939b1623SPeter Collingbourne                break;
1363939b1623SPeter Collingbourne        if (__match == __i) {
13643e519524SHoward Hinnant            // Count number of *__i in [f2, l2)
13653e519524SHoward Hinnant            _D1 __c2 = 0;
13663e519524SHoward Hinnant            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
13673e519524SHoward Hinnant                if (__pred(*__i, *__j))
13683e519524SHoward Hinnant                    ++__c2;
13693e519524SHoward Hinnant            if (__c2 == 0)
13703e519524SHoward Hinnant                return false;
13713e519524SHoward Hinnant            // Count number of *__i in [__i, l1) (we can start with 1)
13723e519524SHoward Hinnant            _D1 __c1 = 1;
1373ce48a113SHoward Hinnant            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
13743e519524SHoward Hinnant                if (__pred(*__i, *__j))
13753e519524SHoward Hinnant                    ++__c1;
13763e519524SHoward Hinnant            if (__c1 != __c2)
13773e519524SHoward Hinnant                return false;
13783e519524SHoward Hinnant        }
13793e519524SHoward Hinnant    }
13803e519524SHoward Hinnant    return true;
13813e519524SHoward Hinnant}
13823e519524SHoward Hinnant
13833e519524SHoward Hinnanttemplate<class _ForwardIterator1, class _ForwardIterator2>
13841362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
13851362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
13863e519524SHoward Hinnantbool
13873e519524SHoward Hinnantis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
13883e519524SHoward Hinnant               _ForwardIterator2 __first2)
13893e519524SHoward Hinnant{
13903e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
13913e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1392ce48a113SHoward Hinnant    return _VSTD::is_permutation(__first1, __last1, __first2, __equal_to<__v1, __v2>());
13933e519524SHoward Hinnant}
13943e519524SHoward Hinnant
13950b0bbd2fSMarshall Clow#if _LIBCPP_STD_VER > 11
13960b0bbd2fSMarshall Clowtemplate<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
139749c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
13980b0bbd2fSMarshall Clow__is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
13990b0bbd2fSMarshall Clow                 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
14000b0bbd2fSMarshall Clow                 _BinaryPredicate __pred,
14010b0bbd2fSMarshall Clow                 forward_iterator_tag, forward_iterator_tag )
14020b0bbd2fSMarshall Clow{
140349c7643cSMarshall Clow//  shorten sequences as much as possible by lopping of any equal prefix
1404847ee131SEric Fiselier    for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
14050b0bbd2fSMarshall Clow        if (!__pred(*__first1, *__first2))
140649c7643cSMarshall Clow            break;
140749c7643cSMarshall Clow    if (__first1 == __last1)
140849c7643cSMarshall Clow        return __first2 == __last2;
140949c7643cSMarshall Clow    else if (__first2 == __last2)
141049c7643cSMarshall Clow        return false;
141149c7643cSMarshall Clow
14120b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
14130b0bbd2fSMarshall Clow    _D1 __l1 = _VSTD::distance(__first1, __last1);
14140b0bbd2fSMarshall Clow
14150b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator2>::difference_type _D2;
1416fce85ba4SMarshall Clow    _D2 __l2 = _VSTD::distance(__first2, __last2);
14170b0bbd2fSMarshall Clow    if (__l1 != __l2)
14180b0bbd2fSMarshall Clow        return false;
14190b0bbd2fSMarshall Clow
14200b0bbd2fSMarshall Clow    // For each element in [f1, l1) see if there are the same number of
14210b0bbd2fSMarshall Clow    //    equal elements in [f2, l2)
14220b0bbd2fSMarshall Clow    for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
14230b0bbd2fSMarshall Clow    {
14240b0bbd2fSMarshall Clow    //  Have we already counted the number of *__i in [f1, l1)?
1425939b1623SPeter Collingbourne        _ForwardIterator1 __match = __first1;
1426939b1623SPeter Collingbourne        for (; __match != __i; ++__match)
1427939b1623SPeter Collingbourne            if (__pred(*__match, *__i))
1428939b1623SPeter Collingbourne                break;
1429939b1623SPeter Collingbourne        if (__match == __i) {
14300b0bbd2fSMarshall Clow            // Count number of *__i in [f2, l2)
14310b0bbd2fSMarshall Clow            _D1 __c2 = 0;
14320b0bbd2fSMarshall Clow            for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
14330b0bbd2fSMarshall Clow                if (__pred(*__i, *__j))
14340b0bbd2fSMarshall Clow                    ++__c2;
14350b0bbd2fSMarshall Clow            if (__c2 == 0)
14360b0bbd2fSMarshall Clow                return false;
14370b0bbd2fSMarshall Clow            // Count number of *__i in [__i, l1) (we can start with 1)
14380b0bbd2fSMarshall Clow            _D1 __c1 = 1;
14390b0bbd2fSMarshall Clow            for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
14400b0bbd2fSMarshall Clow                if (__pred(*__i, *__j))
14410b0bbd2fSMarshall Clow                    ++__c1;
14420b0bbd2fSMarshall Clow            if (__c1 != __c2)
14430b0bbd2fSMarshall Clow                return false;
14440b0bbd2fSMarshall Clow        }
14450b0bbd2fSMarshall Clow    }
14460b0bbd2fSMarshall Clow    return true;
14470b0bbd2fSMarshall Clow}
14480b0bbd2fSMarshall Clow
14490b0bbd2fSMarshall Clowtemplate<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
145049c7643cSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
14510b0bbd2fSMarshall Clow__is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
14520b0bbd2fSMarshall Clow               _RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2,
14530b0bbd2fSMarshall Clow               _BinaryPredicate __pred,
14540b0bbd2fSMarshall Clow               random_access_iterator_tag, random_access_iterator_tag )
14550b0bbd2fSMarshall Clow{
14560b0bbd2fSMarshall Clow    if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
14570b0bbd2fSMarshall Clow        return false;
14580b0bbd2fSMarshall Clow    return _VSTD::is_permutation<_RandomAccessIterator1, _RandomAccessIterator2,
14590b0bbd2fSMarshall Clow                                 typename add_lvalue_reference<_BinaryPredicate>::type>
14600b0bbd2fSMarshall Clow                                (__first1, __last1, __first2, __pred );
14610b0bbd2fSMarshall Clow}
14620b0bbd2fSMarshall Clow
14630b0bbd2fSMarshall Clowtemplate<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
14641362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
14651362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14660b0bbd2fSMarshall Clowbool
14670b0bbd2fSMarshall Clowis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14680b0bbd2fSMarshall Clow               _ForwardIterator2 __first2, _ForwardIterator2 __last2,
14690b0bbd2fSMarshall Clow               _BinaryPredicate __pred )
14700b0bbd2fSMarshall Clow{
14710b0bbd2fSMarshall Clow    return _VSTD::__is_permutation<typename add_lvalue_reference<_BinaryPredicate>::type>
14720b0bbd2fSMarshall Clow       (__first1, __last1, __first2, __last2, __pred,
14730b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator1>::iterator_category(),
14740b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator2>::iterator_category());
14750b0bbd2fSMarshall Clow}
14760b0bbd2fSMarshall Clow
14770b0bbd2fSMarshall Clowtemplate<class _ForwardIterator1, class _ForwardIterator2>
14781362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
14791362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14800b0bbd2fSMarshall Clowbool
14810b0bbd2fSMarshall Clowis_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
14820b0bbd2fSMarshall Clow               _ForwardIterator2 __first2, _ForwardIterator2 __last2)
14830b0bbd2fSMarshall Clow{
14840b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
14850b0bbd2fSMarshall Clow    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
14860b0bbd2fSMarshall Clow    return _VSTD::__is_permutation(__first1, __last1, __first2, __last2,
14870b0bbd2fSMarshall Clow        __equal_to<__v1, __v2>(),
14880b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator1>::iterator_category(),
14890b0bbd2fSMarshall Clow        typename iterator_traits<_ForwardIterator2>::iterator_category());
14900b0bbd2fSMarshall Clow}
14910b0bbd2fSMarshall Clow#endif
14920b0bbd2fSMarshall Clow
14933e519524SHoward Hinnant// search
1494d835e592SMarshall Clow// __search is in <functional>
14953e519524SHoward Hinnant
14963e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
14971362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
14981362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
14993e519524SHoward Hinnant_ForwardIterator1
15003e519524SHoward Hinnantsearch(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15013e519524SHoward Hinnant       _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
15023e519524SHoward Hinnant{
1503ce48a113SHoward Hinnant    return _VSTD::__search<typename add_lvalue_reference<_BinaryPredicate>::type>
15043e519524SHoward Hinnant                         (__first1, __last1, __first2, __last2, __pred,
150528cc4ddeSMarshall Clow                          typename iterator_traits<_ForwardIterator1>::iterator_category(),
150628cc4ddeSMarshall Clow                          typename iterator_traits<_ForwardIterator2>::iterator_category())
150728cc4ddeSMarshall Clow            .first;
15083e519524SHoward Hinnant}
15093e519524SHoward Hinnant
15103e519524SHoward Hinnanttemplate <class _ForwardIterator1, class _ForwardIterator2>
15111362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
15121362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
15133e519524SHoward Hinnant_ForwardIterator1
15143e519524SHoward Hinnantsearch(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
15153e519524SHoward Hinnant       _ForwardIterator2 __first2, _ForwardIterator2 __last2)
15163e519524SHoward Hinnant{
151728cc4ddeSMarshall Clow    typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
151828cc4ddeSMarshall Clow    typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
1519ce48a113SHoward Hinnant    return _VSTD::search(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
15203e519524SHoward Hinnant}
15213e519524SHoward Hinnant
1522d835e592SMarshall Clow
1523d835e592SMarshall Clow#if _LIBCPP_STD_VER > 14
1524d835e592SMarshall Clowtemplate <class _ForwardIterator, class _Searcher>
15251362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1526d835e592SMarshall Clow_ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
1527d835e592SMarshall Clow{ return __s(__f, __l).first; }
1528d835e592SMarshall Clow#endif
1529d835e592SMarshall Clow
15303e519524SHoward Hinnant// search_n
15313e519524SHoward Hinnant
15323e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _ForwardIterator, class _Size, class _Tp>
153312f0a779SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
15343e519524SHoward Hinnant__search_n(_ForwardIterator __first, _ForwardIterator __last,
1535e4383379SHoward Hinnant           _Size __count, const _Tp& __value_, _BinaryPredicate __pred, forward_iterator_tag)
15363e519524SHoward Hinnant{
15373e519524SHoward Hinnant    if (__count <= 0)
15383e519524SHoward Hinnant        return __first;
15393e519524SHoward Hinnant    while (true)
15403e519524SHoward Hinnant    {
1541e4383379SHoward Hinnant        // Find first element in sequence that matchs __value_, with a mininum of loop checks
15423e519524SHoward Hinnant        while (true)
15433e519524SHoward Hinnant        {
1544e4383379SHoward Hinnant            if (__first == __last)  // return __last if no element matches __value_
15453e519524SHoward Hinnant                return __last;
1546e4383379SHoward Hinnant            if (__pred(*__first, __value_))
15473e519524SHoward Hinnant                break;
15483e519524SHoward Hinnant            ++__first;
15493e519524SHoward Hinnant        }
1550e4383379SHoward Hinnant        // *__first matches __value_, now match elements after here
15513e519524SHoward Hinnant        _ForwardIterator __m = __first;
15523e519524SHoward Hinnant        _Size __c(0);
15533e519524SHoward Hinnant        while (true)
15543e519524SHoward Hinnant        {
15553e519524SHoward Hinnant            if (++__c == __count)  // If pattern exhausted, __first is the answer (works for 1 element pattern)
15563e519524SHoward Hinnant                return __first;
15573e519524SHoward Hinnant            if (++__m == __last)  // Otherwise if source exhaused, pattern not found
15583e519524SHoward Hinnant                return __last;
1559e4383379SHoward Hinnant            if (!__pred(*__m, __value_))  // if there is a mismatch, restart with a new __first
15603e519524SHoward Hinnant            {
15613e519524SHoward Hinnant                __first = __m;
15623e519524SHoward Hinnant                ++__first;
15633e519524SHoward Hinnant                break;
15643e519524SHoward Hinnant            }  // else there is a match, check next elements
15653e519524SHoward Hinnant        }
15663e519524SHoward Hinnant    }
15673e519524SHoward Hinnant}
15683e519524SHoward Hinnant
15693e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _RandomAccessIterator, class _Size, class _Tp>
157012f0a779SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
15713e519524SHoward Hinnant__search_n(_RandomAccessIterator __first, _RandomAccessIterator __last,
1572e4383379SHoward Hinnant           _Size __count, const _Tp& __value_, _BinaryPredicate __pred, random_access_iterator_tag)
15733e519524SHoward Hinnant{
15743e519524SHoward Hinnant    if (__count <= 0)
15753e519524SHoward Hinnant        return __first;
15763e519524SHoward Hinnant    _Size __len = static_cast<_Size>(__last - __first);
15773e519524SHoward Hinnant    if (__len < __count)
15783e519524SHoward Hinnant        return __last;
15793e519524SHoward Hinnant    const _RandomAccessIterator __s = __last - (__count - 1);  // Start of pattern match can't go beyond here
15803e519524SHoward Hinnant    while (true)
15813e519524SHoward Hinnant    {
1582e4383379SHoward Hinnant        // Find first element in sequence that matchs __value_, with a mininum of loop checks
15833e519524SHoward Hinnant        while (true)
15843e519524SHoward Hinnant        {
1585b13fcad6SHoward Hinnant            if (__first >= __s)  // return __last if no element matches __value_
15863e519524SHoward Hinnant                return __last;
1587e4383379SHoward Hinnant            if (__pred(*__first, __value_))
15883e519524SHoward Hinnant                break;
15893e519524SHoward Hinnant            ++__first;
15903e519524SHoward Hinnant        }
1591e4383379SHoward Hinnant        // *__first matches __value_, now match elements after here
15923e519524SHoward Hinnant        _RandomAccessIterator __m = __first;
15933e519524SHoward Hinnant        _Size __c(0);
15943e519524SHoward Hinnant        while (true)
15953e519524SHoward Hinnant        {
15963e519524SHoward Hinnant            if (++__c == __count)  // If pattern exhausted, __first is the answer (works for 1 element pattern)
15973e519524SHoward Hinnant                return __first;
15983e519524SHoward Hinnant             ++__m;          // no need to check range on __m because __s guarantees we have enough source
1599e4383379SHoward Hinnant            if (!__pred(*__m, __value_))  // if there is a mismatch, restart with a new __first
16003e519524SHoward Hinnant            {
16013e519524SHoward Hinnant                __first = __m;
16023e519524SHoward Hinnant                ++__first;
16033e519524SHoward Hinnant                break;
16043e519524SHoward Hinnant            }  // else there is a match, check next elements
16053e519524SHoward Hinnant        }
16063e519524SHoward Hinnant    }
16073e519524SHoward Hinnant}
16083e519524SHoward Hinnant
16093e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
16101362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
16111362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
16123e519524SHoward Hinnant_ForwardIterator
16133e519524SHoward Hinnantsearch_n(_ForwardIterator __first, _ForwardIterator __last,
1614e4383379SHoward Hinnant         _Size __count, const _Tp& __value_, _BinaryPredicate __pred)
16153e519524SHoward Hinnant{
1616ce48a113SHoward Hinnant    return _VSTD::__search_n<typename add_lvalue_reference<_BinaryPredicate>::type>
161751544023SEric Fiselier           (__first, __last, __convert_to_integral(__count), __value_, __pred,
161851544023SEric Fiselier           typename iterator_traits<_ForwardIterator>::iterator_category());
16193e519524SHoward Hinnant}
16203e519524SHoward Hinnant
16213e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Size, class _Tp>
16221362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
16231362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
16243e519524SHoward Hinnant_ForwardIterator
1625e4383379SHoward Hinnantsearch_n(_ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value_)
16263e519524SHoward Hinnant{
16273e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
162851544023SEric Fiselier    return _VSTD::search_n(__first, __last, __convert_to_integral(__count),
162951544023SEric Fiselier                           __value_, __equal_to<__v, _Tp>());
16303e519524SHoward Hinnant}
16313e519524SHoward Hinnant
16323e519524SHoward Hinnant// copy
16333e519524SHoward Hinnanttemplate <class _Iter>
16343e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
16353e519524SHoward Hinnant_Iter
16363e519524SHoward Hinnant__unwrap_iter(_Iter __i)
16373e519524SHoward Hinnant{
16383e519524SHoward Hinnant    return __i;
16393e519524SHoward Hinnant}
16403e519524SHoward Hinnant
16413e519524SHoward Hinnanttemplate <class _Tp>
16425b7c98e5SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY
16433e519524SHoward Hinnanttypename enable_if
16443e519524SHoward Hinnant<
1645ca740483SHoward Hinnant    is_trivially_copy_assignable<_Tp>::value,
16463e519524SHoward Hinnant    _Tp*
16473e519524SHoward Hinnant>::type
16483e519524SHoward Hinnant__unwrap_iter(move_iterator<_Tp*> __i)
16493e519524SHoward Hinnant{
16503e519524SHoward Hinnant    return __i.base();
16513e519524SHoward Hinnant}
16523e519524SHoward Hinnant
1653fc88dbd2SHoward Hinnant#if _LIBCPP_DEBUG_LEVEL < 2
1654fc88dbd2SHoward Hinnant
16553e519524SHoward Hinnanttemplate <class _Tp>
16569cad5025SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_IF_NODEBUG
16573e519524SHoward Hinnanttypename enable_if
16583e519524SHoward Hinnant<
1659ca740483SHoward Hinnant    is_trivially_copy_assignable<_Tp>::value,
16603e519524SHoward Hinnant    _Tp*
16613e519524SHoward Hinnant>::type
16623e519524SHoward Hinnant__unwrap_iter(__wrap_iter<_Tp*> __i)
16633e519524SHoward Hinnant{
16643e519524SHoward Hinnant    return __i.base();
16653e519524SHoward Hinnant}
16663e519524SHoward Hinnant
1667c8879ab2SMarshall Clowtemplate <class _Tp>
1668c8879ab2SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_IF_NODEBUG
1669c8879ab2SMarshall Clowtypename enable_if
1670c8879ab2SMarshall Clow<
1671c8879ab2SMarshall Clow    is_trivially_copy_assignable<_Tp>::value,
1672c8879ab2SMarshall Clow    const _Tp*
1673c8879ab2SMarshall Clow>::type
1674c8879ab2SMarshall Clow__unwrap_iter(__wrap_iter<const _Tp*> __i)
1675c8879ab2SMarshall Clow{
1676c8879ab2SMarshall Clow    return __i.base();
1677c8879ab2SMarshall Clow}
1678c8879ab2SMarshall Clow
167914bd0bf0SEric Fiselier#else
168014bd0bf0SEric Fiselier
168114bd0bf0SEric Fiseliertemplate <class _Tp>
16829cad5025SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_IF_NODEBUG
168314bd0bf0SEric Fiseliertypename enable_if
168414bd0bf0SEric Fiselier<
168514bd0bf0SEric Fiselier    is_trivially_copy_assignable<_Tp>::value,
168614bd0bf0SEric Fiselier    __wrap_iter<_Tp*>
168714bd0bf0SEric Fiselier>::type
168814bd0bf0SEric Fiselier__unwrap_iter(__wrap_iter<_Tp*> __i)
168914bd0bf0SEric Fiselier{
169014bd0bf0SEric Fiselier    return __i;
169114bd0bf0SEric Fiselier}
169214bd0bf0SEric Fiselier
1693fc88dbd2SHoward Hinnant#endif  // _LIBCPP_DEBUG_LEVEL < 2
1694fc88dbd2SHoward Hinnant
16953e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
16963e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
16973e519524SHoward Hinnant_OutputIterator
16983e519524SHoward Hinnant__copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
16993e519524SHoward Hinnant{
1700910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
17013e519524SHoward Hinnant        *__result = *__first;
17023e519524SHoward Hinnant    return __result;
17033e519524SHoward Hinnant}
17043e519524SHoward Hinnant
17053e519524SHoward Hinnanttemplate <class _Tp, class _Up>
17063e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17073e519524SHoward Hinnanttypename enable_if
17083e519524SHoward Hinnant<
17093e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1710ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
17113e519524SHoward Hinnant    _Up*
17123e519524SHoward Hinnant>::type
17133e519524SHoward Hinnant__copy(_Tp* __first, _Tp* __last, _Up* __result)
17143e519524SHoward Hinnant{
17153e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
17165b312052SMarshall Clow    if (__n > 0)
1717ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
17183e519524SHoward Hinnant    return __result + __n;
17193e519524SHoward Hinnant}
17203e519524SHoward Hinnant
17213e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
17223e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17233e519524SHoward Hinnant_OutputIterator
17243e519524SHoward Hinnantcopy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
17253e519524SHoward Hinnant{
1726ce48a113SHoward Hinnant    return _VSTD::__copy(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
17273e519524SHoward Hinnant}
17283e519524SHoward Hinnant
17293e519524SHoward Hinnant// copy_backward
17303e519524SHoward Hinnant
1731d3d4356fSHoward Hinnanttemplate <class _BidirectionalIterator, class _OutputIterator>
17323e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17333e519524SHoward Hinnant_OutputIterator
1734d3d4356fSHoward Hinnant__copy_backward(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
17353e519524SHoward Hinnant{
17363e519524SHoward Hinnant    while (__first != __last)
17373e519524SHoward Hinnant        *--__result = *--__last;
17383e519524SHoward Hinnant    return __result;
17393e519524SHoward Hinnant}
17403e519524SHoward Hinnant
17413e519524SHoward Hinnanttemplate <class _Tp, class _Up>
17423e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17433e519524SHoward Hinnanttypename enable_if
17443e519524SHoward Hinnant<
17453e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1746ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
17473e519524SHoward Hinnant    _Up*
17483e519524SHoward Hinnant>::type
17493e519524SHoward Hinnant__copy_backward(_Tp* __first, _Tp* __last, _Up* __result)
17503e519524SHoward Hinnant{
17513e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
17525b312052SMarshall Clow    if (__n > 0)
17535b312052SMarshall Clow    {
17543e519524SHoward Hinnant        __result -= __n;
1755ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
17565b312052SMarshall Clow    }
17573e519524SHoward Hinnant    return __result;
17583e519524SHoward Hinnant}
17593e519524SHoward Hinnant
17603e519524SHoward Hinnanttemplate <class _BidirectionalIterator1, class _BidirectionalIterator2>
17613e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17623e519524SHoward Hinnant_BidirectionalIterator2
17633e519524SHoward Hinnantcopy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
17643e519524SHoward Hinnant              _BidirectionalIterator2 __result)
17653e519524SHoward Hinnant{
1766fd838227SEric Fiselier    return _VSTD::__copy_backward(__unwrap_iter(__first),
1767fd838227SEric Fiselier                                  __unwrap_iter(__last),
1768fd838227SEric Fiselier                                  __unwrap_iter(__result));
17693e519524SHoward Hinnant}
17703e519524SHoward Hinnant
17713e519524SHoward Hinnant// copy_if
17723e519524SHoward Hinnant
17733e519524SHoward Hinnanttemplate<class _InputIterator, class _OutputIterator, class _Predicate>
17743e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17753e519524SHoward Hinnant_OutputIterator
17763e519524SHoward Hinnantcopy_if(_InputIterator __first, _InputIterator __last,
17773e519524SHoward Hinnant        _OutputIterator __result, _Predicate __pred)
17783e519524SHoward Hinnant{
17793e519524SHoward Hinnant    for (; __first != __last; ++__first)
17803e519524SHoward Hinnant    {
17813e519524SHoward Hinnant        if (__pred(*__first))
17823e519524SHoward Hinnant        {
17833e519524SHoward Hinnant            *__result = *__first;
17843e519524SHoward Hinnant            ++__result;
17853e519524SHoward Hinnant        }
17863e519524SHoward Hinnant    }
17873e519524SHoward Hinnant    return __result;
17883e519524SHoward Hinnant}
17893e519524SHoward Hinnant
17903e519524SHoward Hinnant// copy_n
17913e519524SHoward Hinnant
17923e519524SHoward Hinnanttemplate<class _InputIterator, class _Size, class _OutputIterator>
17933e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
17943e519524SHoward Hinnanttypename enable_if
17953e519524SHoward Hinnant<
17963e519524SHoward Hinnant    __is_input_iterator<_InputIterator>::value &&
17973e519524SHoward Hinnant   !__is_random_access_iterator<_InputIterator>::value,
17983e519524SHoward Hinnant    _OutputIterator
17993e519524SHoward Hinnant>::type
180051544023SEric Fiseliercopy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
18013e519524SHoward Hinnant{
180251544023SEric Fiselier    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
180351544023SEric Fiselier    _IntegralSize __n = __orig_n;
180499847d2bSHoward Hinnant    if (__n > 0)
180599847d2bSHoward Hinnant    {
18063e519524SHoward Hinnant        *__result = *__first;
180799847d2bSHoward Hinnant        ++__result;
180899847d2bSHoward Hinnant        for (--__n; __n > 0; --__n)
180999847d2bSHoward Hinnant        {
181099847d2bSHoward Hinnant            ++__first;
181199847d2bSHoward Hinnant            *__result = *__first;
181299847d2bSHoward Hinnant            ++__result;
181399847d2bSHoward Hinnant        }
181499847d2bSHoward Hinnant    }
18153e519524SHoward Hinnant    return __result;
18163e519524SHoward Hinnant}
18173e519524SHoward Hinnant
18183e519524SHoward Hinnanttemplate<class _InputIterator, class _Size, class _OutputIterator>
18193e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18203e519524SHoward Hinnanttypename enable_if
18213e519524SHoward Hinnant<
18223e519524SHoward Hinnant    __is_random_access_iterator<_InputIterator>::value,
18233e519524SHoward Hinnant    _OutputIterator
18243e519524SHoward Hinnant>::type
182551544023SEric Fiseliercopy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
18263e519524SHoward Hinnant{
182751544023SEric Fiselier    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
182851544023SEric Fiselier    _IntegralSize __n = __orig_n;
1829ce48a113SHoward Hinnant    return _VSTD::copy(__first, __first + __n, __result);
18303e519524SHoward Hinnant}
18313e519524SHoward Hinnant
18323e519524SHoward Hinnant// move
18333e519524SHoward Hinnant
18343e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
18353e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18363e519524SHoward Hinnant_OutputIterator
18373e519524SHoward Hinnant__move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18383e519524SHoward Hinnant{
1839910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
1840ce48a113SHoward Hinnant        *__result = _VSTD::move(*__first);
18413e519524SHoward Hinnant    return __result;
18423e519524SHoward Hinnant}
18433e519524SHoward Hinnant
18443e519524SHoward Hinnanttemplate <class _Tp, class _Up>
18453e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18463e519524SHoward Hinnanttypename enable_if
18473e519524SHoward Hinnant<
18483e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1849ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
18503e519524SHoward Hinnant    _Up*
18513e519524SHoward Hinnant>::type
18523e519524SHoward Hinnant__move(_Tp* __first, _Tp* __last, _Up* __result)
18533e519524SHoward Hinnant{
18543e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
18555b312052SMarshall Clow    if (__n > 0)
1856ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
18573e519524SHoward Hinnant    return __result + __n;
18583e519524SHoward Hinnant}
18593e519524SHoward Hinnant
18603e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
18613e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18623e519524SHoward Hinnant_OutputIterator
18633e519524SHoward Hinnantmove(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18643e519524SHoward Hinnant{
1865ce48a113SHoward Hinnant    return _VSTD::__move(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
18663e519524SHoward Hinnant}
18673e519524SHoward Hinnant
18683e519524SHoward Hinnant// move_backward
18693e519524SHoward Hinnant
18703e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
18713e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18723e519524SHoward Hinnant_OutputIterator
18733e519524SHoward Hinnant__move_backward(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
18743e519524SHoward Hinnant{
18753e519524SHoward Hinnant    while (__first != __last)
1876ce48a113SHoward Hinnant        *--__result = _VSTD::move(*--__last);
18773e519524SHoward Hinnant    return __result;
18783e519524SHoward Hinnant}
18793e519524SHoward Hinnant
18803e519524SHoward Hinnanttemplate <class _Tp, class _Up>
18813e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
18823e519524SHoward Hinnanttypename enable_if
18833e519524SHoward Hinnant<
18843e519524SHoward Hinnant    is_same<typename remove_const<_Tp>::type, _Up>::value &&
1885ca740483SHoward Hinnant    is_trivially_copy_assignable<_Up>::value,
18863e519524SHoward Hinnant    _Up*
18873e519524SHoward Hinnant>::type
18883e519524SHoward Hinnant__move_backward(_Tp* __first, _Tp* __last, _Up* __result)
18893e519524SHoward Hinnant{
18903e519524SHoward Hinnant    const size_t __n = static_cast<size_t>(__last - __first);
18915b312052SMarshall Clow    if (__n > 0)
18925b312052SMarshall Clow    {
18933e519524SHoward Hinnant        __result -= __n;
1894ce48a113SHoward Hinnant        _VSTD::memmove(__result, __first, __n * sizeof(_Up));
18955b312052SMarshall Clow    }
18963e519524SHoward Hinnant    return __result;
18973e519524SHoward Hinnant}
18983e519524SHoward Hinnant
18993e519524SHoward Hinnanttemplate <class _BidirectionalIterator1, class _BidirectionalIterator2>
19003e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
19013e519524SHoward Hinnant_BidirectionalIterator2
19023e519524SHoward Hinnantmove_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
19033e519524SHoward Hinnant              _BidirectionalIterator2 __result)
19043e519524SHoward Hinnant{
1905ce48a113SHoward Hinnant    return _VSTD::__move_backward(__unwrap_iter(__first), __unwrap_iter(__last), __unwrap_iter(__result));
19063e519524SHoward Hinnant}
19073e519524SHoward Hinnant
19083e519524SHoward Hinnant// iter_swap
19093e519524SHoward Hinnant
1910a676f7d3SHoward Hinnant// moved to <type_traits> for better swap / noexcept support
19113e519524SHoward Hinnant
19123e519524SHoward Hinnant// transform
19133e519524SHoward Hinnant
19143e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _UnaryOperation>
191599894b61SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19163e519524SHoward Hinnant_OutputIterator
19173e519524SHoward Hinnanttransform(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _UnaryOperation __op)
19183e519524SHoward Hinnant{
1919910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
19203e519524SHoward Hinnant        *__result = __op(*__first);
19213e519524SHoward Hinnant    return __result;
19223e519524SHoward Hinnant}
19233e519524SHoward Hinnant
19243e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _BinaryOperation>
192599894b61SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19263e519524SHoward Hinnant_OutputIterator
19273e519524SHoward Hinnanttransform(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
19283e519524SHoward Hinnant          _OutputIterator __result, _BinaryOperation __binary_op)
19293e519524SHoward Hinnant{
1930910285b2SEric Fiselier    for (; __first1 != __last1; ++__first1, (void) ++__first2, ++__result)
19313e519524SHoward Hinnant        *__result = __binary_op(*__first1, *__first2);
19323e519524SHoward Hinnant    return __result;
19333e519524SHoward Hinnant}
19343e519524SHoward Hinnant
19353e519524SHoward Hinnant// replace
19363e519524SHoward Hinnant
19373e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
193812c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19393e519524SHoward Hinnantvoid
19403e519524SHoward Hinnantreplace(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __old_value, const _Tp& __new_value)
19413e519524SHoward Hinnant{
19423e519524SHoward Hinnant    for (; __first != __last; ++__first)
19433e519524SHoward Hinnant        if (*__first == __old_value)
19443e519524SHoward Hinnant            *__first = __new_value;
19453e519524SHoward Hinnant}
19463e519524SHoward Hinnant
19473e519524SHoward Hinnant// replace_if
19483e519524SHoward Hinnant
19493e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate, class _Tp>
195012c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19513e519524SHoward Hinnantvoid
19523e519524SHoward Hinnantreplace_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, const _Tp& __new_value)
19533e519524SHoward Hinnant{
19543e519524SHoward Hinnant    for (; __first != __last; ++__first)
19553e519524SHoward Hinnant        if (__pred(*__first))
19563e519524SHoward Hinnant            *__first = __new_value;
19573e519524SHoward Hinnant}
19583e519524SHoward Hinnant
19593e519524SHoward Hinnant// replace_copy
19603e519524SHoward Hinnant
19613e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Tp>
196212c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19633e519524SHoward Hinnant_OutputIterator
19643e519524SHoward Hinnantreplace_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
19653e519524SHoward Hinnant             const _Tp& __old_value, const _Tp& __new_value)
19663e519524SHoward Hinnant{
1967910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
19683e519524SHoward Hinnant        if (*__first == __old_value)
19693e519524SHoward Hinnant            *__result = __new_value;
19703e519524SHoward Hinnant        else
19713e519524SHoward Hinnant            *__result = *__first;
19723e519524SHoward Hinnant    return __result;
19733e519524SHoward Hinnant}
19743e519524SHoward Hinnant
19753e519524SHoward Hinnant// replace_copy_if
19763e519524SHoward Hinnant
19773e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Predicate, class _Tp>
197812c7423fSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19793e519524SHoward Hinnant_OutputIterator
19803e519524SHoward Hinnantreplace_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
19813e519524SHoward Hinnant                _Predicate __pred, const _Tp& __new_value)
19823e519524SHoward Hinnant{
1983910285b2SEric Fiselier    for (; __first != __last; ++__first, (void) ++__result)
19843e519524SHoward Hinnant        if (__pred(*__first))
19853e519524SHoward Hinnant            *__result = __new_value;
19863e519524SHoward Hinnant        else
19873e519524SHoward Hinnant            *__result = *__first;
19883e519524SHoward Hinnant    return __result;
19893e519524SHoward Hinnant}
19903e519524SHoward Hinnant
19913e519524SHoward Hinnant// fill_n
19923e519524SHoward Hinnant
19933e519524SHoward Hinnanttemplate <class _OutputIterator, class _Size, class _Tp>
19944bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
19953e519524SHoward Hinnant_OutputIterator
19960f242beaSHoward Hinnant__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
19973e519524SHoward Hinnant{
1998910285b2SEric Fiselier    for (; __n > 0; ++__first, (void) --__n)
1999e4383379SHoward Hinnant        *__first = __value_;
20003e519524SHoward Hinnant    return __first;
20013e519524SHoward Hinnant}
20023e519524SHoward Hinnant
20033e519524SHoward Hinnanttemplate <class _OutputIterator, class _Size, class _Tp>
20044bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20053e519524SHoward Hinnant_OutputIterator
2006e4383379SHoward Hinnantfill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
20073e519524SHoward Hinnant{
200851544023SEric Fiselier   return _VSTD::__fill_n(__first, __convert_to_integral(__n), __value_);
20093e519524SHoward Hinnant}
20103e519524SHoward Hinnant
20113e519524SHoward Hinnant// fill
20123e519524SHoward Hinnant
20133e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
20144bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20153e519524SHoward Hinnantvoid
2016e4383379SHoward Hinnant__fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, forward_iterator_tag)
20173e519524SHoward Hinnant{
20183e519524SHoward Hinnant    for (; __first != __last; ++__first)
2019e4383379SHoward Hinnant        *__first = __value_;
20203e519524SHoward Hinnant}
20213e519524SHoward Hinnant
20223e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Tp>
20234bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20243e519524SHoward Hinnantvoid
2025e4383379SHoward Hinnant__fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value_, random_access_iterator_tag)
20263e519524SHoward Hinnant{
2027e4383379SHoward Hinnant    _VSTD::fill_n(__first, __last - __first, __value_);
20283e519524SHoward Hinnant}
20293e519524SHoward Hinnant
20303e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
20314bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20323e519524SHoward Hinnantvoid
2033e4383379SHoward Hinnantfill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
20343e519524SHoward Hinnant{
2035e4383379SHoward Hinnant    _VSTD::__fill(__first, __last, __value_, typename iterator_traits<_ForwardIterator>::iterator_category());
20363e519524SHoward Hinnant}
20373e519524SHoward Hinnant
20383e519524SHoward Hinnant// generate
20393e519524SHoward Hinnant
20403e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Generator>
20414bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20423e519524SHoward Hinnantvoid
20433e519524SHoward Hinnantgenerate(_ForwardIterator __first, _ForwardIterator __last, _Generator __gen)
20443e519524SHoward Hinnant{
20453e519524SHoward Hinnant    for (; __first != __last; ++__first)
20463e519524SHoward Hinnant        *__first = __gen();
20473e519524SHoward Hinnant}
20483e519524SHoward Hinnant
20493e519524SHoward Hinnant// generate_n
20503e519524SHoward Hinnant
20513e519524SHoward Hinnanttemplate <class _OutputIterator, class _Size, class _Generator>
20524bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
20533e519524SHoward Hinnant_OutputIterator
205451544023SEric Fiseliergenerate_n(_OutputIterator __first, _Size __orig_n, _Generator __gen)
20553e519524SHoward Hinnant{
205651544023SEric Fiselier    typedef decltype(__convert_to_integral(__orig_n)) _IntegralSize;
205751544023SEric Fiselier    _IntegralSize __n = __orig_n;
2058910285b2SEric Fiselier    for (; __n > 0; ++__first, (void) --__n)
20593e519524SHoward Hinnant        *__first = __gen();
20603e519524SHoward Hinnant    return __first;
20613e519524SHoward Hinnant}
20623e519524SHoward Hinnant
20633e519524SHoward Hinnant// remove
20643e519524SHoward Hinnant
20653e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
20661362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
2067e4383379SHoward Hinnantremove(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
20683e519524SHoward Hinnant{
2069e4383379SHoward Hinnant    __first = _VSTD::find(__first, __last, __value_);
20703e519524SHoward Hinnant    if (__first != __last)
20713e519524SHoward Hinnant    {
20723e519524SHoward Hinnant        _ForwardIterator __i = __first;
20733e519524SHoward Hinnant        while (++__i != __last)
20743e519524SHoward Hinnant        {
2075e4383379SHoward Hinnant            if (!(*__i == __value_))
20763e519524SHoward Hinnant            {
2077ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
20783e519524SHoward Hinnant                ++__first;
20793e519524SHoward Hinnant            }
20803e519524SHoward Hinnant        }
20813e519524SHoward Hinnant    }
20823e519524SHoward Hinnant    return __first;
20833e519524SHoward Hinnant}
20843e519524SHoward Hinnant
20853e519524SHoward Hinnant// remove_if
20863e519524SHoward Hinnant
20873e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate>
20881362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
20893e519524SHoward Hinnantremove_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
20903e519524SHoward Hinnant{
2091ce48a113SHoward Hinnant    __first = _VSTD::find_if<_ForwardIterator, typename add_lvalue_reference<_Predicate>::type>
20923e519524SHoward Hinnant                           (__first, __last, __pred);
20933e519524SHoward Hinnant    if (__first != __last)
20943e519524SHoward Hinnant    {
20953e519524SHoward Hinnant        _ForwardIterator __i = __first;
20963e519524SHoward Hinnant        while (++__i != __last)
20973e519524SHoward Hinnant        {
20983e519524SHoward Hinnant            if (!__pred(*__i))
20993e519524SHoward Hinnant            {
2100ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
21013e519524SHoward Hinnant                ++__first;
21023e519524SHoward Hinnant            }
21033e519524SHoward Hinnant        }
21043e519524SHoward Hinnant    }
21053e519524SHoward Hinnant    return __first;
21063e519524SHoward Hinnant}
21073e519524SHoward Hinnant
21083e519524SHoward Hinnant// remove_copy
21093e519524SHoward Hinnant
21103e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Tp>
2111e8ea8296SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21123e519524SHoward Hinnant_OutputIterator
2113e4383379SHoward Hinnantremove_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, const _Tp& __value_)
21143e519524SHoward Hinnant{
21153e519524SHoward Hinnant    for (; __first != __last; ++__first)
21163e519524SHoward Hinnant    {
2117e4383379SHoward Hinnant        if (!(*__first == __value_))
21183e519524SHoward Hinnant        {
21193e519524SHoward Hinnant            *__result = *__first;
21203e519524SHoward Hinnant            ++__result;
21213e519524SHoward Hinnant        }
21223e519524SHoward Hinnant    }
21233e519524SHoward Hinnant    return __result;
21243e519524SHoward Hinnant}
21253e519524SHoward Hinnant
21263e519524SHoward Hinnant// remove_copy_if
21273e519524SHoward Hinnant
21283e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _Predicate>
2129e8ea8296SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21303e519524SHoward Hinnant_OutputIterator
21313e519524SHoward Hinnantremove_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred)
21323e519524SHoward Hinnant{
21333e519524SHoward Hinnant    for (; __first != __last; ++__first)
21343e519524SHoward Hinnant    {
21353e519524SHoward Hinnant        if (!__pred(*__first))
21363e519524SHoward Hinnant        {
21373e519524SHoward Hinnant            *__result = *__first;
21383e519524SHoward Hinnant            ++__result;
21393e519524SHoward Hinnant        }
21403e519524SHoward Hinnant    }
21413e519524SHoward Hinnant    return __result;
21423e519524SHoward Hinnant}
21433e519524SHoward Hinnant
21443e519524SHoward Hinnant// unique
21453e519524SHoward Hinnant
21463e519524SHoward Hinnanttemplate <class _ForwardIterator, class _BinaryPredicate>
21471362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
21483e519524SHoward Hinnantunique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
21493e519524SHoward Hinnant{
2150ce48a113SHoward Hinnant    __first = _VSTD::adjacent_find<_ForwardIterator, typename add_lvalue_reference<_BinaryPredicate>::type>
21513e519524SHoward Hinnant                                 (__first, __last, __pred);
21523e519524SHoward Hinnant    if (__first != __last)
21533e519524SHoward Hinnant    {
21543e519524SHoward Hinnant        // ...  a  a  ?  ...
21553e519524SHoward Hinnant        //      f     i
21563e519524SHoward Hinnant        _ForwardIterator __i = __first;
21573e519524SHoward Hinnant        for (++__i; ++__i != __last;)
21583e519524SHoward Hinnant            if (!__pred(*__first, *__i))
2159ce48a113SHoward Hinnant                *++__first = _VSTD::move(*__i);
21603e519524SHoward Hinnant        ++__first;
21613e519524SHoward Hinnant    }
21623e519524SHoward Hinnant    return __first;
21633e519524SHoward Hinnant}
21643e519524SHoward Hinnant
21653e519524SHoward Hinnanttemplate <class _ForwardIterator>
21661362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
21671362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
21683e519524SHoward Hinnant_ForwardIterator
21693e519524SHoward Hinnantunique(_ForwardIterator __first, _ForwardIterator __last)
21703e519524SHoward Hinnant{
21713e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type __v;
2172ce48a113SHoward Hinnant    return _VSTD::unique(__first, __last, __equal_to<__v>());
21733e519524SHoward Hinnant}
21743e519524SHoward Hinnant
21753e519524SHoward Hinnant// unique_copy
21763e519524SHoward Hinnant
21773e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _InputIterator, class _OutputIterator>
21784bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
21793e519524SHoward Hinnant__unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
21803e519524SHoward Hinnant              input_iterator_tag, output_iterator_tag)
21813e519524SHoward Hinnant{
21823e519524SHoward Hinnant    if (__first != __last)
21833e519524SHoward Hinnant    {
21843e519524SHoward Hinnant        typename iterator_traits<_InputIterator>::value_type __t(*__first);
21853e519524SHoward Hinnant        *__result = __t;
21863e519524SHoward Hinnant        ++__result;
21873e519524SHoward Hinnant        while (++__first != __last)
21883e519524SHoward Hinnant        {
21893e519524SHoward Hinnant            if (!__pred(__t, *__first))
21903e519524SHoward Hinnant            {
21913e519524SHoward Hinnant                __t = *__first;
21923e519524SHoward Hinnant                *__result = __t;
21933e519524SHoward Hinnant                ++__result;
21943e519524SHoward Hinnant            }
21953e519524SHoward Hinnant        }
21963e519524SHoward Hinnant    }
21973e519524SHoward Hinnant    return __result;
21983e519524SHoward Hinnant}
21993e519524SHoward Hinnant
22003e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _ForwardIterator, class _OutputIterator>
22014bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
22023e519524SHoward Hinnant__unique_copy(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
22033e519524SHoward Hinnant              forward_iterator_tag, output_iterator_tag)
22043e519524SHoward Hinnant{
22053e519524SHoward Hinnant    if (__first != __last)
22063e519524SHoward Hinnant    {
22073e519524SHoward Hinnant        _ForwardIterator __i = __first;
22083e519524SHoward Hinnant        *__result = *__i;
22093e519524SHoward Hinnant        ++__result;
22103e519524SHoward Hinnant        while (++__first != __last)
22113e519524SHoward Hinnant        {
22123e519524SHoward Hinnant            if (!__pred(*__i, *__first))
22133e519524SHoward Hinnant            {
22143e519524SHoward Hinnant                *__result = *__first;
22153e519524SHoward Hinnant                ++__result;
22163e519524SHoward Hinnant                __i = __first;
22173e519524SHoward Hinnant            }
22183e519524SHoward Hinnant        }
22193e519524SHoward Hinnant    }
22203e519524SHoward Hinnant    return __result;
22213e519524SHoward Hinnant}
22223e519524SHoward Hinnant
22233e519524SHoward Hinnanttemplate <class _BinaryPredicate, class _InputIterator, class _ForwardIterator>
22244bfb9313SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
22253e519524SHoward Hinnant__unique_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result, _BinaryPredicate __pred,
22263e519524SHoward Hinnant              input_iterator_tag, forward_iterator_tag)
22273e519524SHoward Hinnant{
22283e519524SHoward Hinnant    if (__first != __last)
22293e519524SHoward Hinnant    {
22303e519524SHoward Hinnant        *__result = *__first;
22313e519524SHoward Hinnant        while (++__first != __last)
22323e519524SHoward Hinnant            if (!__pred(*__result, *__first))
22333e519524SHoward Hinnant                *++__result = *__first;
22343e519524SHoward Hinnant        ++__result;
22353e519524SHoward Hinnant    }
22363e519524SHoward Hinnant    return __result;
22373e519524SHoward Hinnant}
22383e519524SHoward Hinnant
22393e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
22404bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22413e519524SHoward Hinnant_OutputIterator
22423e519524SHoward Hinnantunique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred)
22433e519524SHoward Hinnant{
2244ce48a113SHoward Hinnant    return _VSTD::__unique_copy<typename add_lvalue_reference<_BinaryPredicate>::type>
22453e519524SHoward Hinnant                              (__first, __last, __result, __pred,
22463e519524SHoward Hinnant                               typename iterator_traits<_InputIterator>::iterator_category(),
22473e519524SHoward Hinnant                               typename iterator_traits<_OutputIterator>::iterator_category());
22483e519524SHoward Hinnant}
22493e519524SHoward Hinnant
22503e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator>
22514bfb9313SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22523e519524SHoward Hinnant_OutputIterator
22533e519524SHoward Hinnantunique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
22543e519524SHoward Hinnant{
22553e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator>::value_type __v;
2256ce48a113SHoward Hinnant    return _VSTD::unique_copy(__first, __last, __result, __equal_to<__v>());
22573e519524SHoward Hinnant}
22583e519524SHoward Hinnant
22593e519524SHoward Hinnant// reverse
22603e519524SHoward Hinnant
22613e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
22623e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
22633e519524SHoward Hinnantvoid
22643e519524SHoward Hinnant__reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag)
22653e519524SHoward Hinnant{
22663e519524SHoward Hinnant    while (__first != __last)
22673e519524SHoward Hinnant    {
22683e519524SHoward Hinnant        if (__first == --__last)
22693e519524SHoward Hinnant            break;
2270def501d1SMarshall Clow        _VSTD::iter_swap(__first, __last);
22713e519524SHoward Hinnant        ++__first;
22723e519524SHoward Hinnant    }
22733e519524SHoward Hinnant}
22743e519524SHoward Hinnant
22753e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
22763e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
22773e519524SHoward Hinnantvoid
22783e519524SHoward Hinnant__reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag)
22793e519524SHoward Hinnant{
22803e519524SHoward Hinnant    if (__first != __last)
22813e519524SHoward Hinnant        for (; __first < --__last; ++__first)
2282def501d1SMarshall Clow            _VSTD::iter_swap(__first, __last);
22833e519524SHoward Hinnant}
22843e519524SHoward Hinnant
22853e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
22863e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
22873e519524SHoward Hinnantvoid
22883e519524SHoward Hinnantreverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
22893e519524SHoward Hinnant{
2290ce48a113SHoward Hinnant    _VSTD::__reverse(__first, __last, typename iterator_traits<_BidirectionalIterator>::iterator_category());
22913e519524SHoward Hinnant}
22923e519524SHoward Hinnant
22933e519524SHoward Hinnant// reverse_copy
22943e519524SHoward Hinnant
22953e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _OutputIterator>
2296e8ea8296SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
22973e519524SHoward Hinnant_OutputIterator
22983e519524SHoward Hinnantreverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
22993e519524SHoward Hinnant{
23003e519524SHoward Hinnant    for (; __first != __last; ++__result)
23013e519524SHoward Hinnant        *__result = *--__last;
23023e519524SHoward Hinnant    return __result;
23033e519524SHoward Hinnant}
23043e519524SHoward Hinnant
23053e519524SHoward Hinnant// rotate
23063e519524SHoward Hinnant
23073e519524SHoward Hinnanttemplate <class _ForwardIterator>
23083e519524SHoward Hinnant_ForwardIterator
2309aca09de3SHoward Hinnant__rotate_left(_ForwardIterator __first, _ForwardIterator __last)
23103e519524SHoward Hinnant{
2311aca09de3SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
2312aca09de3SHoward Hinnant    value_type __tmp = _VSTD::move(*__first);
2313aca09de3SHoward Hinnant    _ForwardIterator __lm1 = _VSTD::move(_VSTD::next(__first), __last, __first);
2314aca09de3SHoward Hinnant    *__lm1 = _VSTD::move(__tmp);
2315aca09de3SHoward Hinnant    return __lm1;
2316aca09de3SHoward Hinnant}
2317aca09de3SHoward Hinnant
2318aca09de3SHoward Hinnanttemplate <class _BidirectionalIterator>
2319aca09de3SHoward Hinnant_BidirectionalIterator
2320aca09de3SHoward Hinnant__rotate_right(_BidirectionalIterator __first, _BidirectionalIterator __last)
2321aca09de3SHoward Hinnant{
2322aca09de3SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
2323aca09de3SHoward Hinnant    _BidirectionalIterator __lm1 = _VSTD::prev(__last);
2324aca09de3SHoward Hinnant    value_type __tmp = _VSTD::move(*__lm1);
2325aca09de3SHoward Hinnant    _BidirectionalIterator __fp1 = _VSTD::move_backward(__first, __lm1, __last);
2326aca09de3SHoward Hinnant    *__first = _VSTD::move(__tmp);
2327aca09de3SHoward Hinnant    return __fp1;
2328aca09de3SHoward Hinnant}
2329aca09de3SHoward Hinnant
2330aca09de3SHoward Hinnanttemplate <class _ForwardIterator>
2331aca09de3SHoward Hinnant_ForwardIterator
2332aca09de3SHoward Hinnant__rotate_forward(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
2333aca09de3SHoward Hinnant{
23343e519524SHoward Hinnant    _ForwardIterator __i = __middle;
23353e519524SHoward Hinnant    while (true)
23363e519524SHoward Hinnant    {
23373e519524SHoward Hinnant        swap(*__first, *__i);
23383e519524SHoward Hinnant        ++__first;
23393e519524SHoward Hinnant        if (++__i == __last)
23403e519524SHoward Hinnant            break;
23413e519524SHoward Hinnant        if (__first == __middle)
23423e519524SHoward Hinnant            __middle = __i;
23433e519524SHoward Hinnant    }
23443e519524SHoward Hinnant    _ForwardIterator __r = __first;
23453e519524SHoward Hinnant    if (__first != __middle)
23463e519524SHoward Hinnant    {
23473e519524SHoward Hinnant        __i = __middle;
23483e519524SHoward Hinnant        while (true)
23493e519524SHoward Hinnant        {
23503e519524SHoward Hinnant            swap(*__first, *__i);
23513e519524SHoward Hinnant            ++__first;
23523e519524SHoward Hinnant            if (++__i == __last)
23533e519524SHoward Hinnant            {
23543e519524SHoward Hinnant                if (__first == __middle)
23553e519524SHoward Hinnant                    break;
23563e519524SHoward Hinnant                __i = __middle;
23573e519524SHoward Hinnant            }
23583e519524SHoward Hinnant            else if (__first == __middle)
23593e519524SHoward Hinnant                __middle = __i;
23603e519524SHoward Hinnant        }
23613e519524SHoward Hinnant    }
23623e519524SHoward Hinnant    return __r;
23633e519524SHoward Hinnant}
23643e519524SHoward Hinnant
23653e519524SHoward Hinnanttemplate<typename _Integral>
23663e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
23673e519524SHoward Hinnant_Integral
236819b4035fSMarshall Clow__algo_gcd(_Integral __x, _Integral __y)
23693e519524SHoward Hinnant{
23703e519524SHoward Hinnant    do
23713e519524SHoward Hinnant    {
23723e519524SHoward Hinnant        _Integral __t = __x % __y;
23733e519524SHoward Hinnant        __x = __y;
23743e519524SHoward Hinnant        __y = __t;
23753e519524SHoward Hinnant    } while (__y);
23763e519524SHoward Hinnant    return __x;
23773e519524SHoward Hinnant}
23783e519524SHoward Hinnant
23793e519524SHoward Hinnanttemplate<typename _RandomAccessIterator>
23803e519524SHoward Hinnant_RandomAccessIterator
2381aca09de3SHoward Hinnant__rotate_gcd(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
23823e519524SHoward Hinnant{
23833e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
23843e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
23853e519524SHoward Hinnant
23863e519524SHoward Hinnant    const difference_type __m1 = __middle - __first;
23873e519524SHoward Hinnant    const difference_type __m2 = __last - __middle;
23883e519524SHoward Hinnant    if (__m1 == __m2)
23893e519524SHoward Hinnant    {
2390ce48a113SHoward Hinnant        _VSTD::swap_ranges(__first, __middle, __middle);
23913e519524SHoward Hinnant        return __middle;
23923e519524SHoward Hinnant    }
239319b4035fSMarshall Clow    const difference_type __g = _VSTD::__algo_gcd(__m1, __m2);
23943e519524SHoward Hinnant    for (_RandomAccessIterator __p = __first + __g; __p != __first;)
23953e519524SHoward Hinnant    {
2396aca09de3SHoward Hinnant        value_type __t(_VSTD::move(*--__p));
23973e519524SHoward Hinnant        _RandomAccessIterator __p1 = __p;
23983e519524SHoward Hinnant        _RandomAccessIterator __p2 = __p1 + __m1;
23993e519524SHoward Hinnant        do
24003e519524SHoward Hinnant        {
2401aca09de3SHoward Hinnant            *__p1 = _VSTD::move(*__p2);
24023e519524SHoward Hinnant            __p1 = __p2;
24033e519524SHoward Hinnant            const difference_type __d = __last - __p2;
24043e519524SHoward Hinnant            if (__m1 < __d)
24053e519524SHoward Hinnant                __p2 += __m1;
24063e519524SHoward Hinnant            else
24073e519524SHoward Hinnant                __p2 = __first + (__m1 - __d);
24083e519524SHoward Hinnant        } while (__p2 != __p);
2409aca09de3SHoward Hinnant        *__p1 = _VSTD::move(__t);
24103e519524SHoward Hinnant    }
24113e519524SHoward Hinnant    return __first + __m2;
24123e519524SHoward Hinnant}
24133e519524SHoward Hinnant
24143e519524SHoward Hinnanttemplate <class _ForwardIterator>
24153e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
24163e519524SHoward Hinnant_ForwardIterator
2417aca09de3SHoward Hinnant__rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last,
2418aca09de3SHoward Hinnant         _VSTD::forward_iterator_tag)
2419aca09de3SHoward Hinnant{
2420aca09de3SHoward Hinnant    typedef typename _VSTD::iterator_traits<_ForwardIterator>::value_type value_type;
2421aca09de3SHoward Hinnant    if (_VSTD::is_trivially_move_assignable<value_type>::value)
2422aca09de3SHoward Hinnant    {
2423aca09de3SHoward Hinnant        if (_VSTD::next(__first) == __middle)
2424aca09de3SHoward Hinnant            return _VSTD::__rotate_left(__first, __last);
2425aca09de3SHoward Hinnant    }
2426aca09de3SHoward Hinnant    return _VSTD::__rotate_forward(__first, __middle, __last);
2427aca09de3SHoward Hinnant}
2428aca09de3SHoward Hinnant
2429aca09de3SHoward Hinnanttemplate <class _BidirectionalIterator>
2430aca09de3SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
2431aca09de3SHoward Hinnant_BidirectionalIterator
2432aca09de3SHoward Hinnant__rotate(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
2433aca09de3SHoward Hinnant         _VSTD::bidirectional_iterator_tag)
2434aca09de3SHoward Hinnant{
2435aca09de3SHoward Hinnant    typedef typename _VSTD::iterator_traits<_BidirectionalIterator>::value_type value_type;
2436aca09de3SHoward Hinnant    if (_VSTD::is_trivially_move_assignable<value_type>::value)
2437aca09de3SHoward Hinnant    {
2438aca09de3SHoward Hinnant        if (_VSTD::next(__first) == __middle)
2439aca09de3SHoward Hinnant            return _VSTD::__rotate_left(__first, __last);
2440aca09de3SHoward Hinnant        if (_VSTD::next(__middle) == __last)
2441aca09de3SHoward Hinnant            return _VSTD::__rotate_right(__first, __last);
2442aca09de3SHoward Hinnant    }
2443aca09de3SHoward Hinnant    return _VSTD::__rotate_forward(__first, __middle, __last);
2444aca09de3SHoward Hinnant}
2445aca09de3SHoward Hinnant
2446aca09de3SHoward Hinnanttemplate <class _RandomAccessIterator>
2447aca09de3SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
2448aca09de3SHoward Hinnant_RandomAccessIterator
2449aca09de3SHoward Hinnant__rotate(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
2450aca09de3SHoward Hinnant         _VSTD::random_access_iterator_tag)
2451aca09de3SHoward Hinnant{
2452aca09de3SHoward Hinnant    typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::value_type value_type;
2453aca09de3SHoward Hinnant    if (_VSTD::is_trivially_move_assignable<value_type>::value)
2454aca09de3SHoward Hinnant    {
2455aca09de3SHoward Hinnant        if (_VSTD::next(__first) == __middle)
2456aca09de3SHoward Hinnant            return _VSTD::__rotate_left(__first, __last);
2457aca09de3SHoward Hinnant        if (_VSTD::next(__middle) == __last)
2458aca09de3SHoward Hinnant            return _VSTD::__rotate_right(__first, __last);
2459aca09de3SHoward Hinnant        return _VSTD::__rotate_gcd(__first, __middle, __last);
2460aca09de3SHoward Hinnant    }
2461aca09de3SHoward Hinnant    return _VSTD::__rotate_forward(__first, __middle, __last);
2462aca09de3SHoward Hinnant}
2463aca09de3SHoward Hinnant
2464aca09de3SHoward Hinnanttemplate <class _ForwardIterator>
2465aca09de3SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
2466aca09de3SHoward Hinnant_ForwardIterator
24673e519524SHoward Hinnantrotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
24683e519524SHoward Hinnant{
2469aca09de3SHoward Hinnant    if (__first == __middle)
2470aca09de3SHoward Hinnant        return __last;
2471aca09de3SHoward Hinnant    if (__middle == __last)
2472aca09de3SHoward Hinnant        return __first;
2473ce48a113SHoward Hinnant    return _VSTD::__rotate(__first, __middle, __last,
2474aca09de3SHoward Hinnant                           typename _VSTD::iterator_traits<_ForwardIterator>::iterator_category());
24753e519524SHoward Hinnant}
24763e519524SHoward Hinnant
24773e519524SHoward Hinnant// rotate_copy
24783e519524SHoward Hinnant
24793e519524SHoward Hinnanttemplate <class _ForwardIterator, class _OutputIterator>
24803e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
24813e519524SHoward Hinnant_OutputIterator
24823e519524SHoward Hinnantrotate_copy(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, _OutputIterator __result)
24833e519524SHoward Hinnant{
2484ce48a113SHoward Hinnant    return _VSTD::copy(__first, __middle, _VSTD::copy(__middle, __last, __result));
24853e519524SHoward Hinnant}
24863e519524SHoward Hinnant
24873e519524SHoward Hinnant// min_element
24883e519524SHoward Hinnant
24893e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
24901362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
24911362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
24923e519524SHoward Hinnant_ForwardIterator
24930b0671aeSMarshall Clowmin_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
24943e519524SHoward Hinnant{
2495a60d7facSEric Fiselier    static_assert(__is_forward_iterator<_ForwardIterator>::value,
2496a60d7facSEric Fiselier        "std::min_element requires a ForwardIterator");
24973e519524SHoward Hinnant    if (__first != __last)
24983e519524SHoward Hinnant    {
24993e519524SHoward Hinnant        _ForwardIterator __i = __first;
25003e519524SHoward Hinnant        while (++__i != __last)
25013e519524SHoward Hinnant            if (__comp(*__i, *__first))
25023e519524SHoward Hinnant                __first = __i;
25033e519524SHoward Hinnant    }
25043e519524SHoward Hinnant    return __first;
25053e519524SHoward Hinnant}
25063e519524SHoward Hinnant
25073e519524SHoward Hinnanttemplate <class _ForwardIterator>
25081362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25091362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25103e519524SHoward Hinnant_ForwardIterator
25113e519524SHoward Hinnantmin_element(_ForwardIterator __first, _ForwardIterator __last)
25123e519524SHoward Hinnant{
25130b0671aeSMarshall Clow    return _VSTD::min_element(__first, __last,
25144eb27b79SHoward Hinnant              __less<typename iterator_traits<_ForwardIterator>::value_type>());
25154eb27b79SHoward Hinnant}
25164eb27b79SHoward Hinnant
25174eb27b79SHoward Hinnant// min
25184eb27b79SHoward Hinnant
25194eb27b79SHoward Hinnanttemplate <class _Tp, class _Compare>
25201362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25211362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25224eb27b79SHoward Hinnantconst _Tp&
25234eb27b79SHoward Hinnantmin(const _Tp& __a, const _Tp& __b, _Compare __comp)
25244eb27b79SHoward Hinnant{
25254eb27b79SHoward Hinnant    return __comp(__b, __a) ? __b : __a;
25264eb27b79SHoward Hinnant}
25274eb27b79SHoward Hinnant
25284eb27b79SHoward Hinnanttemplate <class _Tp>
25291362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25301362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25314eb27b79SHoward Hinnantconst _Tp&
25324eb27b79SHoward Hinnantmin(const _Tp& __a, const _Tp& __b)
25334eb27b79SHoward Hinnant{
2534ce48a113SHoward Hinnant    return _VSTD::min(__a, __b, __less<_Tp>());
25354eb27b79SHoward Hinnant}
25364eb27b79SHoward Hinnant
2537ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
253854976f26SHoward Hinnant
25394eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
25401362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25411362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25424eb27b79SHoward Hinnant_Tp
25434eb27b79SHoward Hinnantmin(initializer_list<_Tp> __t, _Compare __comp)
25444eb27b79SHoward Hinnant{
25450b0671aeSMarshall Clow    return *_VSTD::min_element(__t.begin(), __t.end(), __comp);
25464eb27b79SHoward Hinnant}
25474eb27b79SHoward Hinnant
25484eb27b79SHoward Hinnanttemplate<class _Tp>
25491362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25501362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25514eb27b79SHoward Hinnant_Tp
25524eb27b79SHoward Hinnantmin(initializer_list<_Tp> __t)
25534eb27b79SHoward Hinnant{
25540b0671aeSMarshall Clow    return *_VSTD::min_element(__t.begin(), __t.end(), __less<_Tp>());
25553e519524SHoward Hinnant}
25563e519524SHoward Hinnant
2557ddda456aSEric Fiselier#endif  // _LIBCPP_CXX03_LANG
255854976f26SHoward Hinnant
25593e519524SHoward Hinnant// max_element
25603e519524SHoward Hinnant
25613e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
25621362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25631362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25643e519524SHoward Hinnant_ForwardIterator
25650b0671aeSMarshall Clowmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
25663e519524SHoward Hinnant{
2567a60d7facSEric Fiselier    static_assert(__is_forward_iterator<_ForwardIterator>::value,
2568a60d7facSEric Fiselier        "std::max_element requires a ForwardIterator");
25693e519524SHoward Hinnant    if (__first != __last)
25703e519524SHoward Hinnant    {
25713e519524SHoward Hinnant        _ForwardIterator __i = __first;
25723e519524SHoward Hinnant        while (++__i != __last)
25733e519524SHoward Hinnant            if (__comp(*__first, *__i))
25743e519524SHoward Hinnant                __first = __i;
25753e519524SHoward Hinnant    }
25763e519524SHoward Hinnant    return __first;
25773e519524SHoward Hinnant}
25783e519524SHoward Hinnant
25799d67c6d5SMarshall Clow
25803e519524SHoward Hinnanttemplate <class _ForwardIterator>
25811362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25821362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25833e519524SHoward Hinnant_ForwardIterator
25843e519524SHoward Hinnantmax_element(_ForwardIterator __first, _ForwardIterator __last)
25853e519524SHoward Hinnant{
25860b0671aeSMarshall Clow    return _VSTD::max_element(__first, __last,
25874eb27b79SHoward Hinnant              __less<typename iterator_traits<_ForwardIterator>::value_type>());
25884eb27b79SHoward Hinnant}
25894eb27b79SHoward Hinnant
25904eb27b79SHoward Hinnant// max
25914eb27b79SHoward Hinnant
25924eb27b79SHoward Hinnanttemplate <class _Tp, class _Compare>
25931362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
25941362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
25954eb27b79SHoward Hinnantconst _Tp&
25964eb27b79SHoward Hinnantmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
25974eb27b79SHoward Hinnant{
25984eb27b79SHoward Hinnant    return __comp(__a, __b) ? __b : __a;
25994eb27b79SHoward Hinnant}
26004eb27b79SHoward Hinnant
26014eb27b79SHoward Hinnanttemplate <class _Tp>
26021362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
26031362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26044eb27b79SHoward Hinnantconst _Tp&
26054eb27b79SHoward Hinnantmax(const _Tp& __a, const _Tp& __b)
26064eb27b79SHoward Hinnant{
2607ce48a113SHoward Hinnant    return _VSTD::max(__a, __b, __less<_Tp>());
26084eb27b79SHoward Hinnant}
26094eb27b79SHoward Hinnant
2610ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
261154976f26SHoward Hinnant
26124eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
26131362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
26141362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26154eb27b79SHoward Hinnant_Tp
26164eb27b79SHoward Hinnantmax(initializer_list<_Tp> __t, _Compare __comp)
26174eb27b79SHoward Hinnant{
26180b0671aeSMarshall Clow    return *_VSTD::max_element(__t.begin(), __t.end(), __comp);
26194eb27b79SHoward Hinnant}
26204eb27b79SHoward Hinnant
26214eb27b79SHoward Hinnanttemplate<class _Tp>
26221362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
26231362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
26244eb27b79SHoward Hinnant_Tp
26254eb27b79SHoward Hinnantmax(initializer_list<_Tp> __t)
26264eb27b79SHoward Hinnant{
26270b0671aeSMarshall Clow    return *_VSTD::max_element(__t.begin(), __t.end(), __less<_Tp>());
26283e519524SHoward Hinnant}
26293e519524SHoward Hinnant
2630ddda456aSEric Fiselier#endif  // _LIBCPP_CXX03_LANG
263154976f26SHoward Hinnant
2632146c14acSMarshall Clow#if _LIBCPP_STD_VER > 14
2633146c14acSMarshall Clow// clamp
2634146c14acSMarshall Clowtemplate<class _Tp, class _Compare>
26351362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
26361362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2637146c14acSMarshall Clowconst _Tp&
2638146c14acSMarshall Clowclamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi, _Compare __comp)
2639146c14acSMarshall Clow{
2640146c14acSMarshall Clow    _LIBCPP_ASSERT(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
2641146c14acSMarshall Clow    return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
2642146c14acSMarshall Clow
2643146c14acSMarshall Clow}
2644146c14acSMarshall Clow
2645146c14acSMarshall Clowtemplate<class _Tp>
26461362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
26471362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2648146c14acSMarshall Clowconst _Tp&
2649146c14acSMarshall Clowclamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi)
2650146c14acSMarshall Clow{
2651146c14acSMarshall Clow    return _VSTD::clamp(__v, __lo, __hi, __less<_Tp>());
2652146c14acSMarshall Clow}
2653146c14acSMarshall Clow#endif
2654146c14acSMarshall Clow
26553e519524SHoward Hinnant// minmax_element
26563e519524SHoward Hinnant
26573e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
26581362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX11
26593e519524SHoward Hinnantstd::pair<_ForwardIterator, _ForwardIterator>
26603e519524SHoward Hinnantminmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
26613e519524SHoward Hinnant{
2662a60d7facSEric Fiselier  static_assert(__is_forward_iterator<_ForwardIterator>::value,
2663a60d7facSEric Fiselier        "std::minmax_element requires a ForwardIterator");
26643e519524SHoward Hinnant  std::pair<_ForwardIterator, _ForwardIterator> __result(__first, __first);
26653e519524SHoward Hinnant  if (__first != __last)
26663e519524SHoward Hinnant  {
26673e519524SHoward Hinnant      if (++__first != __last)
26683e519524SHoward Hinnant      {
26693e519524SHoward Hinnant          if (__comp(*__first, *__result.first))
26703e519524SHoward Hinnant              __result.first = __first;
26713e519524SHoward Hinnant          else
26723e519524SHoward Hinnant              __result.second = __first;
26733e519524SHoward Hinnant          while (++__first != __last)
26743e519524SHoward Hinnant          {
26753e519524SHoward Hinnant              _ForwardIterator __i = __first;
26763e519524SHoward Hinnant              if (++__first == __last)
26773e519524SHoward Hinnant              {
26783e519524SHoward Hinnant                  if (__comp(*__i, *__result.first))
26793e519524SHoward Hinnant                      __result.first = __i;
26803e519524SHoward Hinnant                  else if (!__comp(*__i, *__result.second))
26813e519524SHoward Hinnant                      __result.second = __i;
26823e519524SHoward Hinnant                  break;
26833e519524SHoward Hinnant              }
26843e519524SHoward Hinnant              else
26853e519524SHoward Hinnant              {
26863e519524SHoward Hinnant                  if (__comp(*__first, *__i))
26873e519524SHoward Hinnant                  {
26883e519524SHoward Hinnant                      if (__comp(*__first, *__result.first))
26893e519524SHoward Hinnant                          __result.first = __first;
26903e519524SHoward Hinnant                      if (!__comp(*__i, *__result.second))
26913e519524SHoward Hinnant                          __result.second = __i;
26923e519524SHoward Hinnant                  }
26933e519524SHoward Hinnant                  else
26943e519524SHoward Hinnant                  {
26953e519524SHoward Hinnant                      if (__comp(*__i, *__result.first))
26963e519524SHoward Hinnant                          __result.first = __i;
26973e519524SHoward Hinnant                      if (!__comp(*__first, *__result.second))
26983e519524SHoward Hinnant                          __result.second = __first;
26993e519524SHoward Hinnant                  }
27003e519524SHoward Hinnant              }
27013e519524SHoward Hinnant          }
27023e519524SHoward Hinnant      }
27033e519524SHoward Hinnant  }
27043e519524SHoward Hinnant  return __result;
27053e519524SHoward Hinnant}
27063e519524SHoward Hinnant
27073e519524SHoward Hinnanttemplate <class _ForwardIterator>
27081362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
27091362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27103e519524SHoward Hinnantstd::pair<_ForwardIterator, _ForwardIterator>
27113e519524SHoward Hinnantminmax_element(_ForwardIterator __first, _ForwardIterator __last)
27123e519524SHoward Hinnant{
27139d67c6d5SMarshall Clow    return _VSTD::minmax_element(__first, __last,
27149d67c6d5SMarshall Clow              __less<typename iterator_traits<_ForwardIterator>::value_type>());
27153e519524SHoward Hinnant}
27163e519524SHoward Hinnant
27174eb27b79SHoward Hinnant// minmax
27184eb27b79SHoward Hinnant
27194eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
27201362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
27211362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27224eb27b79SHoward Hinnantpair<const _Tp&, const _Tp&>
27234eb27b79SHoward Hinnantminmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
27244eb27b79SHoward Hinnant{
27254eb27b79SHoward Hinnant    return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) :
27264eb27b79SHoward Hinnant                              pair<const _Tp&, const _Tp&>(__a, __b);
27274eb27b79SHoward Hinnant}
27284eb27b79SHoward Hinnant
27294eb27b79SHoward Hinnanttemplate<class _Tp>
27301362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
27311362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27324eb27b79SHoward Hinnantpair<const _Tp&, const _Tp&>
27334eb27b79SHoward Hinnantminmax(const _Tp& __a, const _Tp& __b)
27344eb27b79SHoward Hinnant{
2735ce48a113SHoward Hinnant    return _VSTD::minmax(__a, __b, __less<_Tp>());
27364eb27b79SHoward Hinnant}
27374eb27b79SHoward Hinnant
2738ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
273954976f26SHoward Hinnant
27404eb27b79SHoward Hinnanttemplate<class _Tp, class _Compare>
27411362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
27421362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27434eb27b79SHoward Hinnantpair<_Tp, _Tp>
27444eb27b79SHoward Hinnantminmax(initializer_list<_Tp> __t, _Compare __comp)
27454eb27b79SHoward Hinnant{
27469d67c6d5SMarshall Clow    typedef typename initializer_list<_Tp>::const_iterator _Iter;
27479d67c6d5SMarshall Clow    _Iter __first = __t.begin();
27489d67c6d5SMarshall Clow    _Iter __last  = __t.end();
27499d67c6d5SMarshall Clow    std::pair<_Tp, _Tp> __result(*__first, *__first);
27509d67c6d5SMarshall Clow
27519d67c6d5SMarshall Clow    ++__first;
27529d67c6d5SMarshall Clow    if (__t.size() % 2 == 0)
27539d67c6d5SMarshall Clow    {
27549d67c6d5SMarshall Clow        if (__comp(*__first,  __result.first))
27559d67c6d5SMarshall Clow            __result.first  = *__first;
27569d67c6d5SMarshall Clow        else
27579d67c6d5SMarshall Clow            __result.second = *__first;
27589d67c6d5SMarshall Clow        ++__first;
27599d67c6d5SMarshall Clow    }
27609d67c6d5SMarshall Clow
27619d67c6d5SMarshall Clow    while (__first != __last)
27629d67c6d5SMarshall Clow    {
27639d67c6d5SMarshall Clow        _Tp __prev = *__first++;
2764002144f6SMarshall Clow        if (__comp(*__first, __prev)) {
2765002144f6SMarshall Clow            if ( __comp(*__first, __result.first)) __result.first  = *__first;
2766002144f6SMarshall Clow            if (!__comp(__prev, __result.second))  __result.second = __prev;
27679d67c6d5SMarshall Clow            }
27689d67c6d5SMarshall Clow        else {
2769002144f6SMarshall Clow            if ( __comp(__prev, __result.first))    __result.first  = __prev;
2770002144f6SMarshall Clow            if (!__comp(*__first, __result.second)) __result.second = *__first;
27719d67c6d5SMarshall Clow            }
27729d67c6d5SMarshall Clow
27739d67c6d5SMarshall Clow        __first++;
27749d67c6d5SMarshall Clow    }
27759d67c6d5SMarshall Clow    return __result;
27769d67c6d5SMarshall Clow}
27779d67c6d5SMarshall Clow
27789d67c6d5SMarshall Clowtemplate<class _Tp>
27791362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
27801362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
27819d67c6d5SMarshall Clowpair<_Tp, _Tp>
27829d67c6d5SMarshall Clowminmax(initializer_list<_Tp> __t)
27839d67c6d5SMarshall Clow{
27849d67c6d5SMarshall Clow    return _VSTD::minmax(__t, __less<_Tp>());
27854eb27b79SHoward Hinnant}
27864eb27b79SHoward Hinnant
2787ddda456aSEric Fiselier#endif  // _LIBCPP_CXX03_LANG
278854976f26SHoward Hinnant
27893e519524SHoward Hinnant// random_shuffle
27903e519524SHoward Hinnant
2791f9d540b0SHoward Hinnant// __independent_bits_engine
2792f9d540b0SHoward Hinnant
2793c003db1fSHoward Hinnanttemplate <unsigned long long _Xp, size_t _Rp>
2794f9d540b0SHoward Hinnantstruct __log2_imp
27953e519524SHoward Hinnant{
2796c003db1fSHoward Hinnant    static const size_t value = _Xp & ((unsigned long long)(1) << _Rp) ? _Rp
2797c003db1fSHoward Hinnant                                           : __log2_imp<_Xp, _Rp - 1>::value;
27983e519524SHoward Hinnant};
27993e519524SHoward Hinnant
2800c003db1fSHoward Hinnanttemplate <unsigned long long _Xp>
2801c003db1fSHoward Hinnantstruct __log2_imp<_Xp, 0>
28023e519524SHoward Hinnant{
2803f9d540b0SHoward Hinnant    static const size_t value = 0;
28043e519524SHoward Hinnant};
28053e519524SHoward Hinnant
2806c003db1fSHoward Hinnanttemplate <size_t _Rp>
2807c003db1fSHoward Hinnantstruct __log2_imp<0, _Rp>
28083e519524SHoward Hinnant{
2809c003db1fSHoward Hinnant    static const size_t value = _Rp + 1;
28103e519524SHoward Hinnant};
28113e519524SHoward Hinnant
281289918caaSEric Fiseliertemplate <class _UIntType, _UIntType _Xp>
2813f9d540b0SHoward Hinnantstruct __log2
28143e519524SHoward Hinnant{
2815c003db1fSHoward Hinnant    static const size_t value = __log2_imp<_Xp,
281689918caaSEric Fiselier                                         sizeof(_UIntType) * __CHAR_BIT__ - 1>::value;
28173e519524SHoward Hinnant};
28183e519524SHoward Hinnant
2819f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2820f9d540b0SHoward Hinnantclass __independent_bits_engine
28213e519524SHoward Hinnant{
2822f9d540b0SHoward Hinnantpublic:
2823f9d540b0SHoward Hinnant    // types
2824f9d540b0SHoward Hinnant    typedef _UIntType result_type;
2825f9d540b0SHoward Hinnant
2826f9d540b0SHoward Hinnantprivate:
2827f9d540b0SHoward Hinnant    typedef typename _Engine::result_type _Engine_result_type;
2828f9d540b0SHoward Hinnant    typedef typename conditional
2829f9d540b0SHoward Hinnant        <
2830f9d540b0SHoward Hinnant            sizeof(_Engine_result_type) <= sizeof(result_type),
2831f9d540b0SHoward Hinnant                result_type,
2832f9d540b0SHoward Hinnant                _Engine_result_type
2833f9d540b0SHoward Hinnant        >::type _Working_result_type;
2834f9d540b0SHoward Hinnant
2835f9d540b0SHoward Hinnant    _Engine& __e_;
2836f9d540b0SHoward Hinnant    size_t __w_;
2837f9d540b0SHoward Hinnant    size_t __w0_;
2838f9d540b0SHoward Hinnant    size_t __n_;
2839f9d540b0SHoward Hinnant    size_t __n0_;
2840f9d540b0SHoward Hinnant    _Working_result_type __y0_;
2841f9d540b0SHoward Hinnant    _Working_result_type __y1_;
2842f9d540b0SHoward Hinnant    _Engine_result_type __mask0_;
2843f9d540b0SHoward Hinnant    _Engine_result_type __mask1_;
2844f9d540b0SHoward Hinnant
2845ddda456aSEric Fiselier#ifdef _LIBCPP_CXX03_LANG
2846c003db1fSHoward Hinnant    static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min
2847f9d540b0SHoward Hinnant                                          + _Working_result_type(1);
2848e386b7b3SHoward Hinnant#else
2849e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min()
2850e386b7b3SHoward Hinnant                                                      + _Working_result_type(1);
2851e386b7b3SHoward Hinnant#endif
2852e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
2853e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
2854e386b7b3SHoward Hinnant    static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
2855f9d540b0SHoward Hinnant
2856f9d540b0SHoward Hinnantpublic:
2857f9d540b0SHoward Hinnant    // constructors and seeding functions
2858f9d540b0SHoward Hinnant    __independent_bits_engine(_Engine& __e, size_t __w);
2859f9d540b0SHoward Hinnant
2860f9d540b0SHoward Hinnant    // generating functions
2861c003db1fSHoward Hinnant    result_type operator()() {return __eval(integral_constant<bool, _Rp != 0>());}
2862f9d540b0SHoward Hinnant
2863f9d540b0SHoward Hinnantprivate:
286408bba64aSMarshall Clow    result_type __eval(false_type);
286508bba64aSMarshall Clow    result_type __eval(true_type);
2866f9d540b0SHoward Hinnant};
2867f9d540b0SHoward Hinnant
2868f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2869f9d540b0SHoward Hinnant__independent_bits_engine<_Engine, _UIntType>
2870f9d540b0SHoward Hinnant    ::__independent_bits_engine(_Engine& __e, size_t __w)
2871f9d540b0SHoward Hinnant        : __e_(__e),
2872f9d540b0SHoward Hinnant          __w_(__w)
2873f9d540b0SHoward Hinnant{
2874f9d540b0SHoward Hinnant    __n_ = __w_ / __m + (__w_ % __m != 0);
2875f9d540b0SHoward Hinnant    __w0_ = __w_ / __n_;
2876c003db1fSHoward Hinnant    if (_Rp == 0)
2877c003db1fSHoward Hinnant        __y0_ = _Rp;
2878f9d540b0SHoward Hinnant    else if (__w0_ < _WDt)
2879c003db1fSHoward Hinnant        __y0_ = (_Rp >> __w0_) << __w0_;
2880f9d540b0SHoward Hinnant    else
2881f9d540b0SHoward Hinnant        __y0_ = 0;
2882c003db1fSHoward Hinnant    if (_Rp - __y0_ > __y0_ / __n_)
2883f9d540b0SHoward Hinnant    {
2884f9d540b0SHoward Hinnant        ++__n_;
2885f9d540b0SHoward Hinnant        __w0_ = __w_ / __n_;
2886f9d540b0SHoward Hinnant        if (__w0_ < _WDt)
2887c003db1fSHoward Hinnant            __y0_ = (_Rp >> __w0_) << __w0_;
2888f9d540b0SHoward Hinnant        else
2889f9d540b0SHoward Hinnant            __y0_ = 0;
2890f9d540b0SHoward Hinnant    }
2891f9d540b0SHoward Hinnant    __n0_ = __n_ - __w_ % __n_;
2892f9d540b0SHoward Hinnant    if (__w0_ < _WDt - 1)
2893c003db1fSHoward Hinnant        __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
2894f9d540b0SHoward Hinnant    else
2895f9d540b0SHoward Hinnant        __y1_ = 0;
2896f9d540b0SHoward Hinnant    __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) :
2897f9d540b0SHoward Hinnant                          _Engine_result_type(0);
2898f9d540b0SHoward Hinnant    __mask1_ = __w0_ < _EDt - 1 ?
2899f9d540b0SHoward Hinnant                               _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) :
2900f9d540b0SHoward Hinnant                               _Engine_result_type(~0);
29013e519524SHoward Hinnant}
29023e519524SHoward Hinnant
2903f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2904f9d540b0SHoward Hinnantinline
2905f9d540b0SHoward Hinnant_UIntType
290608bba64aSMarshall Clow__independent_bits_engine<_Engine, _UIntType>::__eval(false_type)
29073e519524SHoward Hinnant{
2908f9d540b0SHoward Hinnant    return static_cast<result_type>(__e_() & __mask0_);
29093e519524SHoward Hinnant}
29103e519524SHoward Hinnant
2911f9d540b0SHoward Hinnanttemplate<class _Engine, class _UIntType>
2912f9d540b0SHoward Hinnant_UIntType
291308bba64aSMarshall Clow__independent_bits_engine<_Engine, _UIntType>::__eval(true_type)
29143e519524SHoward Hinnant{
29155beb2c3aSMarshall Clow    const size_t _WRt = numeric_limits<result_type>::digits;
2916c003db1fSHoward Hinnant    result_type _Sp = 0;
2917f9d540b0SHoward Hinnant    for (size_t __k = 0; __k < __n0_; ++__k)
2918f9d540b0SHoward Hinnant    {
2919f9d540b0SHoward Hinnant        _Engine_result_type __u;
29203e519524SHoward Hinnant        do
2921f9d540b0SHoward Hinnant        {
2922f9d540b0SHoward Hinnant            __u = __e_() - _Engine::min();
2923f9d540b0SHoward Hinnant        } while (__u >= __y0_);
29245beb2c3aSMarshall Clow        if (__w0_ < _WRt)
2925c003db1fSHoward Hinnant            _Sp <<= __w0_;
2926f9d540b0SHoward Hinnant        else
2927c003db1fSHoward Hinnant            _Sp = 0;
2928c003db1fSHoward Hinnant        _Sp += __u & __mask0_;
2929f9d540b0SHoward Hinnant    }
2930f9d540b0SHoward Hinnant    for (size_t __k = __n0_; __k < __n_; ++__k)
2931f9d540b0SHoward Hinnant    {
2932f9d540b0SHoward Hinnant        _Engine_result_type __u;
2933f9d540b0SHoward Hinnant        do
2934f9d540b0SHoward Hinnant        {
2935f9d540b0SHoward Hinnant            __u = __e_() - _Engine::min();
2936f9d540b0SHoward Hinnant        } while (__u >= __y1_);
29375beb2c3aSMarshall Clow        if (__w0_ < _WRt - 1)
2938c003db1fSHoward Hinnant            _Sp <<= __w0_ + 1;
2939f9d540b0SHoward Hinnant        else
2940c003db1fSHoward Hinnant            _Sp = 0;
2941c003db1fSHoward Hinnant        _Sp += __u & __mask1_;
2942f9d540b0SHoward Hinnant    }
2943c003db1fSHoward Hinnant    return _Sp;
29443e519524SHoward Hinnant}
29453e519524SHoward Hinnant
2946f9d540b0SHoward Hinnant// uniform_int_distribution
29473e519524SHoward Hinnant
2948f9d540b0SHoward Hinnanttemplate<class _IntType = int>
2949f9d540b0SHoward Hinnantclass uniform_int_distribution
29503e519524SHoward Hinnant{
2951f9d540b0SHoward Hinnantpublic:
2952f9d540b0SHoward Hinnant    // types
2953f9d540b0SHoward Hinnant    typedef _IntType result_type;
2954f9d540b0SHoward Hinnant
2955f9d540b0SHoward Hinnant    class param_type
2956f9d540b0SHoward Hinnant    {
2957f9d540b0SHoward Hinnant        result_type __a_;
2958f9d540b0SHoward Hinnant        result_type __b_;
2959f9d540b0SHoward Hinnant    public:
2960f9d540b0SHoward Hinnant        typedef uniform_int_distribution distribution_type;
2961f9d540b0SHoward Hinnant
2962f9d540b0SHoward Hinnant        explicit param_type(result_type __a = 0,
2963f9d540b0SHoward Hinnant                            result_type __b = numeric_limits<result_type>::max())
2964f9d540b0SHoward Hinnant            : __a_(__a), __b_(__b) {}
2965f9d540b0SHoward Hinnant
2966f9d540b0SHoward Hinnant        result_type a() const {return __a_;}
2967f9d540b0SHoward Hinnant        result_type b() const {return __b_;}
2968f9d540b0SHoward Hinnant
2969f9d540b0SHoward Hinnant        friend bool operator==(const param_type& __x, const param_type& __y)
2970f9d540b0SHoward Hinnant            {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;}
2971f9d540b0SHoward Hinnant        friend bool operator!=(const param_type& __x, const param_type& __y)
2972f9d540b0SHoward Hinnant            {return !(__x == __y);}
29733e519524SHoward Hinnant    };
29743e519524SHoward Hinnant
2975f9d540b0SHoward Hinnantprivate:
2976f9d540b0SHoward Hinnant    param_type __p_;
29773e519524SHoward Hinnant
2978f9d540b0SHoward Hinnantpublic:
2979f9d540b0SHoward Hinnant    // constructors and reset functions
2980f9d540b0SHoward Hinnant    explicit uniform_int_distribution(result_type __a = 0,
2981f9d540b0SHoward Hinnant                                      result_type __b = numeric_limits<result_type>::max())
2982f9d540b0SHoward Hinnant        : __p_(param_type(__a, __b)) {}
2983f9d540b0SHoward Hinnant    explicit uniform_int_distribution(const param_type& __p) : __p_(__p) {}
2984f9d540b0SHoward Hinnant    void reset() {}
2985f9d540b0SHoward Hinnant
2986f9d540b0SHoward Hinnant    // generating functions
2987f9d540b0SHoward Hinnant    template<class _URNG> result_type operator()(_URNG& __g)
2988f9d540b0SHoward Hinnant        {return (*this)(__g, __p_);}
2989f9d540b0SHoward Hinnant    template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p);
2990f9d540b0SHoward Hinnant
2991f9d540b0SHoward Hinnant    // property functions
2992f9d540b0SHoward Hinnant    result_type a() const {return __p_.a();}
2993f9d540b0SHoward Hinnant    result_type b() const {return __p_.b();}
2994f9d540b0SHoward Hinnant
2995f9d540b0SHoward Hinnant    param_type param() const {return __p_;}
2996f9d540b0SHoward Hinnant    void param(const param_type& __p) {__p_ = __p;}
2997f9d540b0SHoward Hinnant
2998f9d540b0SHoward Hinnant    result_type min() const {return a();}
2999f9d540b0SHoward Hinnant    result_type max() const {return b();}
3000f9d540b0SHoward Hinnant
3001f9d540b0SHoward Hinnant    friend bool operator==(const uniform_int_distribution& __x,
3002f9d540b0SHoward Hinnant                           const uniform_int_distribution& __y)
3003f9d540b0SHoward Hinnant        {return __x.__p_ == __y.__p_;}
3004f9d540b0SHoward Hinnant    friend bool operator!=(const uniform_int_distribution& __x,
3005f9d540b0SHoward Hinnant                           const uniform_int_distribution& __y)
3006f9d540b0SHoward Hinnant            {return !(__x == __y);}
30073e519524SHoward Hinnant};
30083e519524SHoward Hinnant
3009f9d540b0SHoward Hinnanttemplate<class _IntType>
3010f9d540b0SHoward Hinnanttemplate<class _URNG>
3011f9d540b0SHoward Hinnanttypename uniform_int_distribution<_IntType>::result_type
3012f9d540b0SHoward Hinnantuniform_int_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p)
30132dd53352SMarshall Clow_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
30143e519524SHoward Hinnant{
3015f9d540b0SHoward Hinnant    typedef typename conditional<sizeof(result_type) <= sizeof(uint32_t),
3016f9d540b0SHoward Hinnant                                            uint32_t, uint64_t>::type _UIntType;
30172dd53352SMarshall Clow    const _UIntType _Rp = _UIntType(__p.b()) - _UIntType(__p.a()) + _UIntType(1);
3018c003db1fSHoward Hinnant    if (_Rp == 1)
3019f9d540b0SHoward Hinnant        return __p.a();
3020f9d540b0SHoward Hinnant    const size_t _Dt = numeric_limits<_UIntType>::digits;
3021f9d540b0SHoward Hinnant    typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
3022c003db1fSHoward Hinnant    if (_Rp == 0)
3023f9d540b0SHoward Hinnant        return static_cast<result_type>(_Eng(__g, _Dt)());
3024f3b851f0SMarshall Clow    size_t __w = _Dt - __libcpp_clz(_Rp) - 1;
3025a6438ca1SMarshall Clow    if ((_Rp & (std::numeric_limits<_UIntType>::max() >> (_Dt - __w))) != 0)
3026f9d540b0SHoward Hinnant        ++__w;
3027f9d540b0SHoward Hinnant    _Eng __e(__g, __w);
3028f9d540b0SHoward Hinnant    _UIntType __u;
3029f9d540b0SHoward Hinnant    do
30303e519524SHoward Hinnant    {
3031f9d540b0SHoward Hinnant        __u = __e();
3032c003db1fSHoward Hinnant    } while (__u >= _Rp);
3033f9d540b0SHoward Hinnant    return static_cast<result_type>(__u + __p.a());
30343e519524SHoward Hinnant}
3035f9d540b0SHoward Hinnant
303666f1ec46SEric Fiselier#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) \
303766f1ec46SEric Fiselier  || defined(_LIBCPP_BUILDING_LIBRARY)
3038f0544c20SHoward Hinnantclass _LIBCPP_TYPE_VIS __rs_default;
3039f9d540b0SHoward Hinnant
3040f0544c20SHoward Hinnant_LIBCPP_FUNC_VIS __rs_default __rs_get();
3041f9d540b0SHoward Hinnant
3042f0544c20SHoward Hinnantclass _LIBCPP_TYPE_VIS __rs_default
30433e519524SHoward Hinnant{
3044f9d540b0SHoward Hinnant    static unsigned __c_;
3045f9d540b0SHoward Hinnant
3046f9d540b0SHoward Hinnant    __rs_default();
3047f9d540b0SHoward Hinnantpublic:
3048b6e5f854SMarshall Clow    typedef uint_fast32_t result_type;
3049f9d540b0SHoward Hinnant
3050f9d540b0SHoward Hinnant    static const result_type _Min = 0;
3051f9d540b0SHoward Hinnant    static const result_type _Max = 0xFFFFFFFF;
3052f9d540b0SHoward Hinnant
3053f9d540b0SHoward Hinnant    __rs_default(const __rs_default&);
3054f9d540b0SHoward Hinnant    ~__rs_default();
3055f9d540b0SHoward Hinnant
3056f9d540b0SHoward Hinnant    result_type operator()();
3057f9d540b0SHoward Hinnant
3058788c9979SHoward Hinnant    static _LIBCPP_CONSTEXPR result_type min() {return _Min;}
3059788c9979SHoward Hinnant    static _LIBCPP_CONSTEXPR result_type max() {return _Max;}
3060f9d540b0SHoward Hinnant
3061f0544c20SHoward Hinnant    friend _LIBCPP_FUNC_VIS __rs_default __rs_get();
3062f9d540b0SHoward Hinnant};
3063f9d540b0SHoward Hinnant
3064f0544c20SHoward Hinnant_LIBCPP_FUNC_VIS __rs_default __rs_get();
30653e519524SHoward Hinnant
30663e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
3067ea5cd3b4SLouis Dionne_LIBCPP_DEPRECATED_IN_CXX14 void
30683e519524SHoward Hinnantrandom_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
30693e519524SHoward Hinnant{
30703e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3071c003db1fSHoward Hinnant    typedef uniform_int_distribution<ptrdiff_t> _Dp;
3072c003db1fSHoward Hinnant    typedef typename _Dp::param_type _Pp;
30733e519524SHoward Hinnant    difference_type __d = __last - __first;
30743e519524SHoward Hinnant    if (__d > 1)
30753e519524SHoward Hinnant    {
3076c003db1fSHoward Hinnant        _Dp __uid;
3077f9d540b0SHoward Hinnant        __rs_default __g = __rs_get();
30785a8525e0SMarshall Clow        for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
3079007b26beSHoward Hinnant        {
3080c003db1fSHoward Hinnant            difference_type __i = __uid(__g, _Pp(0, __d));
3081007b26beSHoward Hinnant            if (__i != difference_type(0))
3082007b26beSHoward Hinnant                swap(*__first, *(__first + __i));
3083007b26beSHoward Hinnant        }
30843e519524SHoward Hinnant    }
30853e519524SHoward Hinnant}
30863e519524SHoward Hinnant
30873e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _RandomNumberGenerator>
3088ea5cd3b4SLouis Dionne_LIBCPP_DEPRECATED_IN_CXX14 void
30893e519524SHoward Hinnantrandom_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3090ddda456aSEric Fiselier#ifndef _LIBCPP_CXX03_LANG
30913e519524SHoward Hinnant               _RandomNumberGenerator&& __rand)
30923e519524SHoward Hinnant#else
30933e519524SHoward Hinnant               _RandomNumberGenerator& __rand)
30943e519524SHoward Hinnant#endif
30953e519524SHoward Hinnant{
30963e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
30973e519524SHoward Hinnant    difference_type __d = __last - __first;
30983e519524SHoward Hinnant    if (__d > 1)
30993e519524SHoward Hinnant    {
31005a8525e0SMarshall Clow        for (--__last; __first < __last; ++__first, (void) --__d)
3101007b26beSHoward Hinnant        {
3102007b26beSHoward Hinnant            difference_type __i = __rand(__d);
3103e9cc5451SMarshall Clow            if (__i != difference_type(0))
3104007b26beSHoward Hinnant              swap(*__first, *(__first + __i));
3105007b26beSHoward Hinnant        }
31063e519524SHoward Hinnant    }
31073e519524SHoward Hinnant}
31080f37a410SMarshall Clow#endif
31093e519524SHoward Hinnant
3110e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3111e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3112e7154709SEric Fiselier_LIBCPP_INLINE_VISIBILITY
3113e7154709SEric Fiselier_SampleIterator __sample(_PopulationIterator __first,
311442bfedd9SAlexander Richardson                         _PopulationIterator __last, _SampleIterator __output_iter,
3115e7154709SEric Fiselier                         _Distance __n,
3116e7154709SEric Fiselier                         _UniformRandomNumberGenerator & __g,
3117e7154709SEric Fiselier                         input_iterator_tag) {
3118e7154709SEric Fiselier
3119e7154709SEric Fiselier  _Distance __k = 0;
3120e7154709SEric Fiselier  for (; __first != __last && __k < __n; ++__first, (void) ++__k)
312142bfedd9SAlexander Richardson    __output_iter[__k] = *__first;
3122e7154709SEric Fiselier  _Distance __sz = __k;
3123e7154709SEric Fiselier  for (; __first != __last; ++__first, (void) ++__k) {
3124e7154709SEric Fiselier    _Distance __r = _VSTD::uniform_int_distribution<_Distance>(0, __k)(__g);
3125e7154709SEric Fiselier    if (__r < __sz)
312642bfedd9SAlexander Richardson      __output_iter[__r] = *__first;
3127e7154709SEric Fiselier  }
312842bfedd9SAlexander Richardson  return __output_iter + _VSTD::min(__n, __k);
3129e7154709SEric Fiselier}
3130e7154709SEric Fiselier
3131e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3132e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3133e7154709SEric Fiselier_LIBCPP_INLINE_VISIBILITY
3134e7154709SEric Fiselier_SampleIterator __sample(_PopulationIterator __first,
313542bfedd9SAlexander Richardson                         _PopulationIterator __last, _SampleIterator __output_iter,
3136e7154709SEric Fiselier                         _Distance __n,
3137e7154709SEric Fiselier                         _UniformRandomNumberGenerator& __g,
3138e7154709SEric Fiselier                         forward_iterator_tag) {
3139e7154709SEric Fiselier  _Distance __unsampled_sz = _VSTD::distance(__first, __last);
3140e7154709SEric Fiselier  for (__n = _VSTD::min(__n, __unsampled_sz); __n != 0; ++__first) {
3141e7154709SEric Fiselier    _Distance __r =
3142e7154709SEric Fiselier        _VSTD::uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
3143e7154709SEric Fiselier    if (__r < __n) {
314442bfedd9SAlexander Richardson      *__output_iter++ = *__first;
3145e7154709SEric Fiselier      --__n;
3146e7154709SEric Fiselier    }
3147e7154709SEric Fiselier  }
314842bfedd9SAlexander Richardson  return __output_iter;
3149e7154709SEric Fiselier}
3150e7154709SEric Fiselier
3151e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3152e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3153e7154709SEric Fiselier_LIBCPP_INLINE_VISIBILITY
3154e7154709SEric Fiselier_SampleIterator __sample(_PopulationIterator __first,
315542bfedd9SAlexander Richardson                         _PopulationIterator __last, _SampleIterator __output_iter,
3156e7154709SEric Fiselier                         _Distance __n, _UniformRandomNumberGenerator& __g) {
3157e7154709SEric Fiselier  typedef typename iterator_traits<_PopulationIterator>::iterator_category
3158e7154709SEric Fiselier        _PopCategory;
3159e7154709SEric Fiselier  typedef typename iterator_traits<_PopulationIterator>::difference_type
3160e7154709SEric Fiselier        _Difference;
3161e7154709SEric Fiselier  static_assert(__is_forward_iterator<_PopulationIterator>::value ||
3162e7154709SEric Fiselier                __is_random_access_iterator<_SampleIterator>::value,
3163e7154709SEric Fiselier                "SampleIterator must meet the requirements of RandomAccessIterator");
3164e7154709SEric Fiselier  typedef typename common_type<_Distance, _Difference>::type _CommonType;
3165e7154709SEric Fiselier  _LIBCPP_ASSERT(__n >= 0, "N must be a positive number.");
3166e7154709SEric Fiselier  return _VSTD::__sample(
316742bfedd9SAlexander Richardson      __first, __last, __output_iter, _CommonType(__n),
3168e7154709SEric Fiselier      __g, _PopCategory());
3169e7154709SEric Fiselier}
3170e7154709SEric Fiselier
3171e7154709SEric Fiselier#if _LIBCPP_STD_VER > 14
3172e7154709SEric Fiseliertemplate <class _PopulationIterator, class _SampleIterator, class _Distance,
3173e7154709SEric Fiselier          class _UniformRandomNumberGenerator>
3174e7154709SEric Fiselierinline _LIBCPP_INLINE_VISIBILITY
3175e7154709SEric Fiselier_SampleIterator sample(_PopulationIterator __first,
317642bfedd9SAlexander Richardson                       _PopulationIterator __last, _SampleIterator __output_iter,
3177e7154709SEric Fiselier                       _Distance __n, _UniformRandomNumberGenerator&& __g) {
317842bfedd9SAlexander Richardson    return _VSTD::__sample(__first, __last, __output_iter, __n, __g);
3179e7154709SEric Fiselier}
3180e7154709SEric Fiselier#endif // _LIBCPP_STD_VER > 14
3181e7154709SEric Fiselier
3182f9d540b0SHoward Hinnanttemplate<class _RandomAccessIterator, class _UniformRandomNumberGenerator>
3183f9d540b0SHoward Hinnant    void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
3184fb340102SHoward Hinnant                 _UniformRandomNumberGenerator&& __g)
3185f9d540b0SHoward Hinnant{
3186f9d540b0SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
3187c003db1fSHoward Hinnant    typedef uniform_int_distribution<ptrdiff_t> _Dp;
3188c003db1fSHoward Hinnant    typedef typename _Dp::param_type _Pp;
3189f9d540b0SHoward Hinnant    difference_type __d = __last - __first;
3190f9d540b0SHoward Hinnant    if (__d > 1)
3191f9d540b0SHoward Hinnant    {
3192c003db1fSHoward Hinnant        _Dp __uid;
3193*7fa68653SMarshall Clow        for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
3194007b26beSHoward Hinnant        {
3195c003db1fSHoward Hinnant            difference_type __i = __uid(__g, _Pp(0, __d));
3196007b26beSHoward Hinnant            if (__i != difference_type(0))
3197007b26beSHoward Hinnant                swap(*__first, *(__first + __i));
3198007b26beSHoward Hinnant        }
3199f9d540b0SHoward Hinnant    }
3200f9d540b0SHoward Hinnant}
3201f9d540b0SHoward Hinnant
32023e519524SHoward Hinnanttemplate <class _InputIterator, class _Predicate>
32031362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
32043e519524SHoward Hinnantis_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred)
32053e519524SHoward Hinnant{
32063e519524SHoward Hinnant    for (; __first != __last; ++__first)
32073e519524SHoward Hinnant        if (!__pred(*__first))
32083e519524SHoward Hinnant            break;
3209b9595b79SMarshall Clow    if ( __first == __last )
3210b9595b79SMarshall Clow        return true;
3211b9595b79SMarshall Clow    ++__first;
32123e519524SHoward Hinnant    for (; __first != __last; ++__first)
32133e519524SHoward Hinnant        if (__pred(*__first))
32143e519524SHoward Hinnant            return false;
32153e519524SHoward Hinnant    return true;
32163e519524SHoward Hinnant}
32173e519524SHoward Hinnant
32183e519524SHoward Hinnant// partition
32193e519524SHoward Hinnant
32203e519524SHoward Hinnanttemplate <class _Predicate, class _ForwardIterator>
32213e519524SHoward Hinnant_ForwardIterator
32223e519524SHoward Hinnant__partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag)
32233e519524SHoward Hinnant{
32243e519524SHoward Hinnant    while (true)
32253e519524SHoward Hinnant    {
32263e519524SHoward Hinnant        if (__first == __last)
32273e519524SHoward Hinnant            return __first;
32283e519524SHoward Hinnant        if (!__pred(*__first))
32293e519524SHoward Hinnant            break;
32303e519524SHoward Hinnant        ++__first;
32313e519524SHoward Hinnant    }
32323e519524SHoward Hinnant    for (_ForwardIterator __p = __first; ++__p != __last;)
32333e519524SHoward Hinnant    {
32343e519524SHoward Hinnant        if (__pred(*__p))
32353e519524SHoward Hinnant        {
32363e519524SHoward Hinnant            swap(*__first, *__p);
32373e519524SHoward Hinnant            ++__first;
32383e519524SHoward Hinnant        }
32393e519524SHoward Hinnant    }
32403e519524SHoward Hinnant    return __first;
32413e519524SHoward Hinnant}
32423e519524SHoward Hinnant
32433e519524SHoward Hinnanttemplate <class _Predicate, class _BidirectionalIterator>
32443e519524SHoward Hinnant_BidirectionalIterator
32453e519524SHoward Hinnant__partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
32463e519524SHoward Hinnant            bidirectional_iterator_tag)
32473e519524SHoward Hinnant{
32483e519524SHoward Hinnant    while (true)
32493e519524SHoward Hinnant    {
32503e519524SHoward Hinnant        while (true)
32513e519524SHoward Hinnant        {
32523e519524SHoward Hinnant            if (__first == __last)
32533e519524SHoward Hinnant                return __first;
32543e519524SHoward Hinnant            if (!__pred(*__first))
32553e519524SHoward Hinnant                break;
32563e519524SHoward Hinnant            ++__first;
32573e519524SHoward Hinnant        }
32583e519524SHoward Hinnant        do
32593e519524SHoward Hinnant        {
32603e519524SHoward Hinnant            if (__first == --__last)
32613e519524SHoward Hinnant                return __first;
32623e519524SHoward Hinnant        } while (!__pred(*__last));
32633e519524SHoward Hinnant        swap(*__first, *__last);
32643e519524SHoward Hinnant        ++__first;
32653e519524SHoward Hinnant    }
32663e519524SHoward Hinnant}
32673e519524SHoward Hinnant
32683e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate>
32693e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
32703e519524SHoward Hinnant_ForwardIterator
32713e519524SHoward Hinnantpartition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
32723e519524SHoward Hinnant{
3273ce48a113SHoward Hinnant    return _VSTD::__partition<typename add_lvalue_reference<_Predicate>::type>
32743e519524SHoward Hinnant                            (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
32753e519524SHoward Hinnant}
32763e519524SHoward Hinnant
32773e519524SHoward Hinnant// partition_copy
32783e519524SHoward Hinnant
32793e519524SHoward Hinnanttemplate <class _InputIterator, class _OutputIterator1,
32803e519524SHoward Hinnant          class _OutputIterator2, class _Predicate>
32811b9a4ffdSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_OutputIterator1, _OutputIterator2>
32823e519524SHoward Hinnantpartition_copy(_InputIterator __first, _InputIterator __last,
32833e519524SHoward Hinnant               _OutputIterator1 __out_true, _OutputIterator2 __out_false,
32843e519524SHoward Hinnant               _Predicate __pred)
32853e519524SHoward Hinnant{
32863e519524SHoward Hinnant    for (; __first != __last; ++__first)
32873e519524SHoward Hinnant    {
32883e519524SHoward Hinnant        if (__pred(*__first))
32893e519524SHoward Hinnant        {
32903e519524SHoward Hinnant            *__out_true = *__first;
32913e519524SHoward Hinnant            ++__out_true;
32923e519524SHoward Hinnant        }
32933e519524SHoward Hinnant        else
32943e519524SHoward Hinnant        {
32953e519524SHoward Hinnant            *__out_false = *__first;
32963e519524SHoward Hinnant            ++__out_false;
32973e519524SHoward Hinnant        }
32983e519524SHoward Hinnant    }
32993e519524SHoward Hinnant    return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
33003e519524SHoward Hinnant}
33013e519524SHoward Hinnant
33023e519524SHoward Hinnant// partition_point
33033e519524SHoward Hinnant
33043e519524SHoward Hinnanttemplate<class _ForwardIterator, class _Predicate>
3305674f9128SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
33063e519524SHoward Hinnantpartition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
33073e519524SHoward Hinnant{
33083e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
3309ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
33103e519524SHoward Hinnant    while (__len != 0)
33113e519524SHoward Hinnant    {
331204695a75SLouis Dionne        difference_type __l2 = _VSTD::__half_positive(__len);
33133e519524SHoward Hinnant        _ForwardIterator __m = __first;
3314ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
33153e519524SHoward Hinnant        if (__pred(*__m))
33163e519524SHoward Hinnant        {
33173e519524SHoward Hinnant            __first = ++__m;
33183e519524SHoward Hinnant            __len -= __l2 + 1;
33193e519524SHoward Hinnant        }
33203e519524SHoward Hinnant        else
33213e519524SHoward Hinnant            __len = __l2;
33223e519524SHoward Hinnant    }
33233e519524SHoward Hinnant    return __first;
33243e519524SHoward Hinnant}
33253e519524SHoward Hinnant
33263e519524SHoward Hinnant// stable_partition
33273e519524SHoward Hinnant
33283e519524SHoward Hinnanttemplate <class _Predicate, class _ForwardIterator, class _Distance, class _Pair>
33293e519524SHoward Hinnant_ForwardIterator
33303e519524SHoward Hinnant__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
33313e519524SHoward Hinnant                   _Distance __len, _Pair __p, forward_iterator_tag __fit)
33323e519524SHoward Hinnant{
33333e519524SHoward Hinnant    // *__first is known to be false
33343e519524SHoward Hinnant    // __len >= 1
33353e519524SHoward Hinnant    if (__len == 1)
33363e519524SHoward Hinnant        return __first;
33373e519524SHoward Hinnant    if (__len == 2)
33383e519524SHoward Hinnant    {
33393e519524SHoward Hinnant        _ForwardIterator __m = __first;
33403e519524SHoward Hinnant        if (__pred(*++__m))
33413e519524SHoward Hinnant        {
33423e519524SHoward Hinnant            swap(*__first, *__m);
33433e519524SHoward Hinnant            return __m;
33443e519524SHoward Hinnant        }
33453e519524SHoward Hinnant        return __first;
33463e519524SHoward Hinnant    }
33473e519524SHoward Hinnant    if (__len <= __p.second)
33483e519524SHoward Hinnant    {   // The buffer is big enough to use
33493e519524SHoward Hinnant        typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
33503e519524SHoward Hinnant        __destruct_n __d(0);
33513e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
33523e519524SHoward Hinnant        // Move the falses into the temporary buffer, and the trues to the front of the line
33533e519524SHoward Hinnant        // Update __first to always point to the end of the trues
33543e519524SHoward Hinnant        value_type* __t = __p.first;
3355ce48a113SHoward Hinnant        ::new(__t) value_type(_VSTD::move(*__first));
33563e519524SHoward Hinnant        __d.__incr((value_type*)0);
33573e519524SHoward Hinnant        ++__t;
33583e519524SHoward Hinnant        _ForwardIterator __i = __first;
33593e519524SHoward Hinnant        while (++__i != __last)
33603e519524SHoward Hinnant        {
33613e519524SHoward Hinnant            if (__pred(*__i))
33623e519524SHoward Hinnant            {
3363ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
33643e519524SHoward Hinnant                ++__first;
33653e519524SHoward Hinnant            }
33663e519524SHoward Hinnant            else
33673e519524SHoward Hinnant            {
3368ce48a113SHoward Hinnant                ::new(__t) value_type(_VSTD::move(*__i));
33693e519524SHoward Hinnant                __d.__incr((value_type*)0);
33703e519524SHoward Hinnant                ++__t;
33713e519524SHoward Hinnant            }
33723e519524SHoward Hinnant        }
33733e519524SHoward Hinnant        // All trues now at start of range, all falses in buffer
33743e519524SHoward Hinnant        // Move falses back into range, but don't mess up __first which points to first false
33753e519524SHoward Hinnant        __i = __first;
3376*7fa68653SMarshall Clow        for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
3377ce48a113SHoward Hinnant            *__i = _VSTD::move(*__t2);
33783e519524SHoward Hinnant        // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
33793e519524SHoward Hinnant        return __first;
33803e519524SHoward Hinnant    }
33813e519524SHoward Hinnant    // Else not enough buffer, do in place
33823e519524SHoward Hinnant    // __len >= 3
33833e519524SHoward Hinnant    _ForwardIterator __m = __first;
33843e519524SHoward Hinnant    _Distance __len2 = __len / 2;  // __len2 >= 2
3385ce48a113SHoward Hinnant    _VSTD::advance(__m, __len2);
33863e519524SHoward Hinnant    // recurse on [__first, __m), *__first know to be false
33873e519524SHoward Hinnant    // F?????????????????
33883e519524SHoward Hinnant    // f       m         l
33893e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
33903e519524SHoward Hinnant    _ForwardIterator __first_false = __stable_partition<_PredRef>(__first, __m, __pred, __len2, __p, __fit);
33913e519524SHoward Hinnant    // TTTFFFFF??????????
33923e519524SHoward Hinnant    // f  ff   m         l
33933e519524SHoward Hinnant    // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
33943e519524SHoward Hinnant    _ForwardIterator __m1 = __m;
33953e519524SHoward Hinnant    _ForwardIterator __second_false = __last;
33963e519524SHoward Hinnant    _Distance __len_half = __len - __len2;
33973e519524SHoward Hinnant    while (__pred(*__m1))
33983e519524SHoward Hinnant    {
33993e519524SHoward Hinnant        if (++__m1 == __last)
34003e519524SHoward Hinnant            goto __second_half_done;
34013e519524SHoward Hinnant        --__len_half;
34023e519524SHoward Hinnant    }
34033e519524SHoward Hinnant    // TTTFFFFFTTTF??????
34043e519524SHoward Hinnant    // f  ff   m  m1     l
34053e519524SHoward Hinnant    __second_false = __stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __fit);
34063e519524SHoward Hinnant__second_half_done:
34073e519524SHoward Hinnant    // TTTFFFFFTTTTTFFFFF
34083e519524SHoward Hinnant    // f  ff   m    sf   l
3409ce48a113SHoward Hinnant    return _VSTD::rotate(__first_false, __m, __second_false);
34103e519524SHoward Hinnant    // TTTTTTTTFFFFFFFFFF
34113e519524SHoward Hinnant    //         |
34123e519524SHoward Hinnant}
34133e519524SHoward Hinnant
34143e519524SHoward Hinnantstruct __return_temporary_buffer
34153e519524SHoward Hinnant{
34163e519524SHoward Hinnant    template <class _Tp>
3417ce48a113SHoward Hinnant    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::return_temporary_buffer(__p);}
34183e519524SHoward Hinnant};
34193e519524SHoward Hinnant
34203e519524SHoward Hinnanttemplate <class _Predicate, class _ForwardIterator>
34213e519524SHoward Hinnant_ForwardIterator
34223e519524SHoward Hinnant__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
34233e519524SHoward Hinnant                   forward_iterator_tag)
34243e519524SHoward Hinnant{
34253e519524SHoward Hinnant    const unsigned __alloc_limit = 3;  // might want to make this a function of trivial assignment
34263e519524SHoward Hinnant    // Either prove all true and return __first or point to first false
34273e519524SHoward Hinnant    while (true)
34283e519524SHoward Hinnant    {
34293e519524SHoward Hinnant        if (__first == __last)
34303e519524SHoward Hinnant            return __first;
34313e519524SHoward Hinnant        if (!__pred(*__first))
34323e519524SHoward Hinnant            break;
34333e519524SHoward Hinnant        ++__first;
34343e519524SHoward Hinnant    }
34353e519524SHoward Hinnant    // We now have a reduced range [__first, __last)
34363e519524SHoward Hinnant    // *__first is known to be false
34373e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
34383e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3439ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
34403e519524SHoward Hinnant    pair<value_type*, ptrdiff_t> __p(0, 0);
34413e519524SHoward Hinnant    unique_ptr<value_type, __return_temporary_buffer> __h;
34423e519524SHoward Hinnant    if (__len >= __alloc_limit)
34433e519524SHoward Hinnant    {
3444ce48a113SHoward Hinnant        __p = _VSTD::get_temporary_buffer<value_type>(__len);
34453e519524SHoward Hinnant        __h.reset(__p.first);
34463e519524SHoward Hinnant    }
34473e519524SHoward Hinnant    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
34483e519524SHoward Hinnant                             (__first, __last, __pred, __len, __p, forward_iterator_tag());
34493e519524SHoward Hinnant}
34503e519524SHoward Hinnant
34513e519524SHoward Hinnanttemplate <class _Predicate, class _BidirectionalIterator, class _Distance, class _Pair>
34523e519524SHoward Hinnant_BidirectionalIterator
34533e519524SHoward Hinnant__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
34543e519524SHoward Hinnant                   _Distance __len, _Pair __p, bidirectional_iterator_tag __bit)
34553e519524SHoward Hinnant{
34563e519524SHoward Hinnant    // *__first is known to be false
34573e519524SHoward Hinnant    // *__last is known to be true
34583e519524SHoward Hinnant    // __len >= 2
34593e519524SHoward Hinnant    if (__len == 2)
34603e519524SHoward Hinnant    {
34613e519524SHoward Hinnant        swap(*__first, *__last);
34623e519524SHoward Hinnant        return __last;
34633e519524SHoward Hinnant    }
34643e519524SHoward Hinnant    if (__len == 3)
34653e519524SHoward Hinnant    {
34663e519524SHoward Hinnant        _BidirectionalIterator __m = __first;
34673e519524SHoward Hinnant        if (__pred(*++__m))
34683e519524SHoward Hinnant        {
34693e519524SHoward Hinnant            swap(*__first, *__m);
34703e519524SHoward Hinnant            swap(*__m, *__last);
34713e519524SHoward Hinnant            return __last;
34723e519524SHoward Hinnant        }
34733e519524SHoward Hinnant        swap(*__m, *__last);
34743e519524SHoward Hinnant        swap(*__first, *__m);
34753e519524SHoward Hinnant        return __m;
34763e519524SHoward Hinnant    }
34773e519524SHoward Hinnant    if (__len <= __p.second)
34783e519524SHoward Hinnant    {   // The buffer is big enough to use
34793e519524SHoward Hinnant        typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
34803e519524SHoward Hinnant        __destruct_n __d(0);
34813e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
34823e519524SHoward Hinnant        // Move the falses into the temporary buffer, and the trues to the front of the line
34833e519524SHoward Hinnant        // Update __first to always point to the end of the trues
34843e519524SHoward Hinnant        value_type* __t = __p.first;
3485ce48a113SHoward Hinnant        ::new(__t) value_type(_VSTD::move(*__first));
34863e519524SHoward Hinnant        __d.__incr((value_type*)0);
34873e519524SHoward Hinnant        ++__t;
34883e519524SHoward Hinnant        _BidirectionalIterator __i = __first;
34893e519524SHoward Hinnant        while (++__i != __last)
34903e519524SHoward Hinnant        {
34913e519524SHoward Hinnant            if (__pred(*__i))
34923e519524SHoward Hinnant            {
3493ce48a113SHoward Hinnant                *__first = _VSTD::move(*__i);
34943e519524SHoward Hinnant                ++__first;
34953e519524SHoward Hinnant            }
34963e519524SHoward Hinnant            else
34973e519524SHoward Hinnant            {
3498ce48a113SHoward Hinnant                ::new(__t) value_type(_VSTD::move(*__i));
34993e519524SHoward Hinnant                __d.__incr((value_type*)0);
35003e519524SHoward Hinnant                ++__t;
35013e519524SHoward Hinnant            }
35023e519524SHoward Hinnant        }
35033e519524SHoward Hinnant        // move *__last, known to be true
3504ce48a113SHoward Hinnant        *__first = _VSTD::move(*__i);
35053e519524SHoward Hinnant        __i = ++__first;
35063e519524SHoward Hinnant        // All trues now at start of range, all falses in buffer
35073e519524SHoward Hinnant        // Move falses back into range, but don't mess up __first which points to first false
3508*7fa68653SMarshall Clow        for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
3509ce48a113SHoward Hinnant            *__i = _VSTD::move(*__t2);
35103e519524SHoward Hinnant        // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
35113e519524SHoward Hinnant        return __first;
35123e519524SHoward Hinnant    }
35133e519524SHoward Hinnant    // Else not enough buffer, do in place
35143e519524SHoward Hinnant    // __len >= 4
35153e519524SHoward Hinnant    _BidirectionalIterator __m = __first;
35163e519524SHoward Hinnant    _Distance __len2 = __len / 2;  // __len2 >= 2
3517ce48a113SHoward Hinnant    _VSTD::advance(__m, __len2);
35183e519524SHoward Hinnant    // recurse on [__first, __m-1], except reduce __m-1 until *(__m-1) is true, *__first know to be false
35193e519524SHoward Hinnant    // F????????????????T
35203e519524SHoward Hinnant    // f       m        l
35213e519524SHoward Hinnant    _BidirectionalIterator __m1 = __m;
35223e519524SHoward Hinnant    _BidirectionalIterator __first_false = __first;
35233e519524SHoward Hinnant    _Distance __len_half = __len2;
35243e519524SHoward Hinnant    while (!__pred(*--__m1))
35253e519524SHoward Hinnant    {
35263e519524SHoward Hinnant        if (__m1 == __first)
35273e519524SHoward Hinnant            goto __first_half_done;
35283e519524SHoward Hinnant        --__len_half;
35293e519524SHoward Hinnant    }
35303e519524SHoward Hinnant    // F???TFFF?????????T
35313e519524SHoward Hinnant    // f   m1  m        l
35323e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
35333e519524SHoward Hinnant    __first_false = __stable_partition<_PredRef>(__first, __m1, __pred, __len_half, __p, __bit);
35343e519524SHoward Hinnant__first_half_done:
35353e519524SHoward Hinnant    // TTTFFFFF?????????T
35363e519524SHoward Hinnant    // f  ff   m        l
35373e519524SHoward Hinnant    // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
35383e519524SHoward Hinnant    __m1 = __m;
35393e519524SHoward Hinnant    _BidirectionalIterator __second_false = __last;
35403e519524SHoward Hinnant    ++__second_false;
35413e519524SHoward Hinnant    __len_half = __len - __len2;
35423e519524SHoward Hinnant    while (__pred(*__m1))
35433e519524SHoward Hinnant    {
35443e519524SHoward Hinnant        if (++__m1 == __last)
35453e519524SHoward Hinnant            goto __second_half_done;
35463e519524SHoward Hinnant        --__len_half;
35473e519524SHoward Hinnant    }
35483e519524SHoward Hinnant    // TTTFFFFFTTTF?????T
35493e519524SHoward Hinnant    // f  ff   m  m1    l
35503e519524SHoward Hinnant    __second_false = __stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __bit);
35513e519524SHoward Hinnant__second_half_done:
35523e519524SHoward Hinnant    // TTTFFFFFTTTTTFFFFF
35533e519524SHoward Hinnant    // f  ff   m    sf  l
3554ce48a113SHoward Hinnant    return _VSTD::rotate(__first_false, __m, __second_false);
35553e519524SHoward Hinnant    // TTTTTTTTFFFFFFFFFF
35563e519524SHoward Hinnant    //         |
35573e519524SHoward Hinnant}
35583e519524SHoward Hinnant
35593e519524SHoward Hinnanttemplate <class _Predicate, class _BidirectionalIterator>
35603e519524SHoward Hinnant_BidirectionalIterator
35613e519524SHoward Hinnant__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
35623e519524SHoward Hinnant                   bidirectional_iterator_tag)
35633e519524SHoward Hinnant{
35643e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
35653e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
35663e519524SHoward Hinnant    const difference_type __alloc_limit = 4;  // might want to make this a function of trivial assignment
35673e519524SHoward Hinnant    // Either prove all true and return __first or point to first false
35683e519524SHoward Hinnant    while (true)
35693e519524SHoward Hinnant    {
35703e519524SHoward Hinnant        if (__first == __last)
35713e519524SHoward Hinnant            return __first;
35723e519524SHoward Hinnant        if (!__pred(*__first))
35733e519524SHoward Hinnant            break;
35743e519524SHoward Hinnant        ++__first;
35753e519524SHoward Hinnant    }
35763e519524SHoward Hinnant    // __first points to first false, everything prior to __first is already set.
35773e519524SHoward Hinnant    // Either prove [__first, __last) is all false and return __first, or point __last to last true
35783e519524SHoward Hinnant    do
35793e519524SHoward Hinnant    {
35803e519524SHoward Hinnant        if (__first == --__last)
35813e519524SHoward Hinnant            return __first;
35823e519524SHoward Hinnant    } while (!__pred(*__last));
35833e519524SHoward Hinnant    // We now have a reduced range [__first, __last]
35843e519524SHoward Hinnant    // *__first is known to be false
35853e519524SHoward Hinnant    // *__last is known to be true
35863e519524SHoward Hinnant    // __len >= 2
3587ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last) + 1;
35883e519524SHoward Hinnant    pair<value_type*, ptrdiff_t> __p(0, 0);
35893e519524SHoward Hinnant    unique_ptr<value_type, __return_temporary_buffer> __h;
35903e519524SHoward Hinnant    if (__len >= __alloc_limit)
35913e519524SHoward Hinnant    {
3592ce48a113SHoward Hinnant        __p = _VSTD::get_temporary_buffer<value_type>(__len);
35933e519524SHoward Hinnant        __h.reset(__p.first);
35943e519524SHoward Hinnant    }
35953e519524SHoward Hinnant    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
35963e519524SHoward Hinnant                             (__first, __last, __pred, __len, __p, bidirectional_iterator_tag());
35973e519524SHoward Hinnant}
35983e519524SHoward Hinnant
35993e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Predicate>
36003e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
36013e519524SHoward Hinnant_ForwardIterator
36023e519524SHoward Hinnantstable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
36033e519524SHoward Hinnant{
36043e519524SHoward Hinnant    return __stable_partition<typename add_lvalue_reference<_Predicate>::type>
36053e519524SHoward Hinnant                             (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
36063e519524SHoward Hinnant}
36073e519524SHoward Hinnant
36083e519524SHoward Hinnant// is_sorted_until
36093e519524SHoward Hinnant
36103e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
36111362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
36123e519524SHoward Hinnantis_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
36133e519524SHoward Hinnant{
36143e519524SHoward Hinnant    if (__first != __last)
36153e519524SHoward Hinnant    {
36163e519524SHoward Hinnant        _ForwardIterator __i = __first;
36173e519524SHoward Hinnant        while (++__i != __last)
36183e519524SHoward Hinnant        {
36193e519524SHoward Hinnant            if (__comp(*__i, *__first))
36203e519524SHoward Hinnant                return __i;
36213e519524SHoward Hinnant            __first = __i;
36223e519524SHoward Hinnant        }
36233e519524SHoward Hinnant    }
36243e519524SHoward Hinnant    return __last;
36253e519524SHoward Hinnant}
36263e519524SHoward Hinnant
36273e519524SHoward Hinnanttemplate<class _ForwardIterator>
36281362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
36291362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36303e519524SHoward Hinnant_ForwardIterator
36313e519524SHoward Hinnantis_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
36323e519524SHoward Hinnant{
3633ce48a113SHoward Hinnant    return _VSTD::is_sorted_until(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
36343e519524SHoward Hinnant}
36353e519524SHoward Hinnant
36363e519524SHoward Hinnant// is_sorted
36373e519524SHoward Hinnant
36383e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Compare>
36391362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
36401362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36413e519524SHoward Hinnantbool
36423e519524SHoward Hinnantis_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
36433e519524SHoward Hinnant{
3644ce48a113SHoward Hinnant    return _VSTD::is_sorted_until(__first, __last, __comp) == __last;
36453e519524SHoward Hinnant}
36463e519524SHoward Hinnant
36473e519524SHoward Hinnanttemplate<class _ForwardIterator>
36481362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
36491362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
36503e519524SHoward Hinnantbool
36513e519524SHoward Hinnantis_sorted(_ForwardIterator __first, _ForwardIterator __last)
36523e519524SHoward Hinnant{
3653ce48a113SHoward Hinnant    return _VSTD::is_sorted(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
36543e519524SHoward Hinnant}
36553e519524SHoward Hinnant
36563e519524SHoward Hinnant// sort
36573e519524SHoward Hinnant
36583e519524SHoward Hinnant// stable, 2-3 compares, 0-2 swaps
36593e519524SHoward Hinnant
36603e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator>
36613e519524SHoward Hinnantunsigned
36623e519524SHoward Hinnant__sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c)
36633e519524SHoward Hinnant{
36643e519524SHoward Hinnant    unsigned __r = 0;
36653e519524SHoward Hinnant    if (!__c(*__y, *__x))          // if x <= y
36663e519524SHoward Hinnant    {
36673e519524SHoward Hinnant        if (!__c(*__z, *__y))      // if y <= z
36683e519524SHoward Hinnant            return __r;            // x <= y && y <= z
36693e519524SHoward Hinnant                                   // x <= y && y > z
36703e519524SHoward Hinnant        swap(*__y, *__z);          // x <= z && y < z
36713e519524SHoward Hinnant        __r = 1;
36723e519524SHoward Hinnant        if (__c(*__y, *__x))       // if x > y
36733e519524SHoward Hinnant        {
36743e519524SHoward Hinnant            swap(*__x, *__y);      // x < y && y <= z
36753e519524SHoward Hinnant            __r = 2;
36763e519524SHoward Hinnant        }
36773e519524SHoward Hinnant        return __r;                // x <= y && y < z
36783e519524SHoward Hinnant    }
36793e519524SHoward Hinnant    if (__c(*__z, *__y))           // x > y, if y > z
36803e519524SHoward Hinnant    {
36813e519524SHoward Hinnant        swap(*__x, *__z);          // x < y && y < z
36823e519524SHoward Hinnant        __r = 1;
36833e519524SHoward Hinnant        return __r;
36843e519524SHoward Hinnant    }
36853e519524SHoward Hinnant    swap(*__x, *__y);              // x > y && y <= z
36863e519524SHoward Hinnant    __r = 1;                       // x < y && x <= z
36873e519524SHoward Hinnant    if (__c(*__z, *__y))           // if y > z
36883e519524SHoward Hinnant    {
36893e519524SHoward Hinnant        swap(*__y, *__z);          // x <= y && y < z
36903e519524SHoward Hinnant        __r = 2;
36913e519524SHoward Hinnant    }
36923e519524SHoward Hinnant    return __r;
36933e519524SHoward Hinnant}                                  // x <= y && y <= z
36943e519524SHoward Hinnant
36953e519524SHoward Hinnant// stable, 3-6 compares, 0-5 swaps
36963e519524SHoward Hinnant
36973e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator>
36983e519524SHoward Hinnantunsigned
36993e519524SHoward Hinnant__sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
37003e519524SHoward Hinnant            _ForwardIterator __x4, _Compare __c)
37013e519524SHoward Hinnant{
37023e519524SHoward Hinnant    unsigned __r = __sort3<_Compare>(__x1, __x2, __x3, __c);
37033e519524SHoward Hinnant    if (__c(*__x4, *__x3))
37043e519524SHoward Hinnant    {
37053e519524SHoward Hinnant        swap(*__x3, *__x4);
37063e519524SHoward Hinnant        ++__r;
37073e519524SHoward Hinnant        if (__c(*__x3, *__x2))
37083e519524SHoward Hinnant        {
37093e519524SHoward Hinnant            swap(*__x2, *__x3);
37103e519524SHoward Hinnant            ++__r;
37113e519524SHoward Hinnant            if (__c(*__x2, *__x1))
37123e519524SHoward Hinnant            {
37133e519524SHoward Hinnant                swap(*__x1, *__x2);
37143e519524SHoward Hinnant                ++__r;
37153e519524SHoward Hinnant            }
37163e519524SHoward Hinnant        }
37173e519524SHoward Hinnant    }
37183e519524SHoward Hinnant    return __r;
37193e519524SHoward Hinnant}
37203e519524SHoward Hinnant
37213e519524SHoward Hinnant// stable, 4-10 compares, 0-9 swaps
37223e519524SHoward Hinnant
37233e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator>
3724835140a4SLouis Dionne_LIBCPP_HIDDEN
37253e519524SHoward Hinnantunsigned
37263e519524SHoward Hinnant__sort5(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
37273e519524SHoward Hinnant            _ForwardIterator __x4, _ForwardIterator __x5, _Compare __c)
37283e519524SHoward Hinnant{
37293e519524SHoward Hinnant    unsigned __r = __sort4<_Compare>(__x1, __x2, __x3, __x4, __c);
37303e519524SHoward Hinnant    if (__c(*__x5, *__x4))
37313e519524SHoward Hinnant    {
37323e519524SHoward Hinnant        swap(*__x4, *__x5);
37333e519524SHoward Hinnant        ++__r;
37343e519524SHoward Hinnant        if (__c(*__x4, *__x3))
37353e519524SHoward Hinnant        {
37363e519524SHoward Hinnant            swap(*__x3, *__x4);
37373e519524SHoward Hinnant            ++__r;
37383e519524SHoward Hinnant            if (__c(*__x3, *__x2))
37393e519524SHoward Hinnant            {
37403e519524SHoward Hinnant                swap(*__x2, *__x3);
37413e519524SHoward Hinnant                ++__r;
37423e519524SHoward Hinnant                if (__c(*__x2, *__x1))
37433e519524SHoward Hinnant                {
37443e519524SHoward Hinnant                    swap(*__x1, *__x2);
37453e519524SHoward Hinnant                    ++__r;
37463e519524SHoward Hinnant                }
37473e519524SHoward Hinnant            }
37483e519524SHoward Hinnant        }
37493e519524SHoward Hinnant    }
37503e519524SHoward Hinnant    return __r;
37513e519524SHoward Hinnant}
37523e519524SHoward Hinnant
37533e519524SHoward Hinnant// Assumes size > 0
37543e519524SHoward Hinnanttemplate <class _Compare, class _BirdirectionalIterator>
37553e519524SHoward Hinnantvoid
37563e519524SHoward Hinnant__selection_sort(_BirdirectionalIterator __first, _BirdirectionalIterator __last, _Compare __comp)
37573e519524SHoward Hinnant{
37583e519524SHoward Hinnant    _BirdirectionalIterator __lm1 = __last;
37593e519524SHoward Hinnant    for (--__lm1; __first != __lm1; ++__first)
37603e519524SHoward Hinnant    {
3761ce48a113SHoward Hinnant        _BirdirectionalIterator __i = _VSTD::min_element<_BirdirectionalIterator,
37623e519524SHoward Hinnant                                                        typename add_lvalue_reference<_Compare>::type>
37633e519524SHoward Hinnant                                                       (__first, __last, __comp);
37643e519524SHoward Hinnant        if (__i != __first)
37653e519524SHoward Hinnant            swap(*__first, *__i);
37663e519524SHoward Hinnant    }
37673e519524SHoward Hinnant}
37683e519524SHoward Hinnant
37693e519524SHoward Hinnanttemplate <class _Compare, class _BirdirectionalIterator>
37703e519524SHoward Hinnantvoid
37713e519524SHoward Hinnant__insertion_sort(_BirdirectionalIterator __first, _BirdirectionalIterator __last, _Compare __comp)
37723e519524SHoward Hinnant{
37733e519524SHoward Hinnant    typedef typename iterator_traits<_BirdirectionalIterator>::value_type value_type;
37743e519524SHoward Hinnant    if (__first != __last)
37753e519524SHoward Hinnant    {
37763e519524SHoward Hinnant        _BirdirectionalIterator __i = __first;
37773e519524SHoward Hinnant        for (++__i; __i != __last; ++__i)
37783e519524SHoward Hinnant        {
37793e519524SHoward Hinnant            _BirdirectionalIterator __j = __i;
3780ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__j));
37813e519524SHoward Hinnant            for (_BirdirectionalIterator __k = __i; __k != __first && __comp(__t,  *--__k); --__j)
3782ce48a113SHoward Hinnant                *__j = _VSTD::move(*__k);
3783ce48a113SHoward Hinnant            *__j = _VSTD::move(__t);
37843e519524SHoward Hinnant        }
37853e519524SHoward Hinnant    }
37863e519524SHoward Hinnant}
37873e519524SHoward Hinnant
37883e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
37893e519524SHoward Hinnantvoid
37903e519524SHoward Hinnant__insertion_sort_3(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
37913e519524SHoward Hinnant{
37923e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
37933e519524SHoward Hinnant    _RandomAccessIterator __j = __first+2;
37943e519524SHoward Hinnant    __sort3<_Compare>(__first, __first+1, __j, __comp);
37953e519524SHoward Hinnant    for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
37963e519524SHoward Hinnant    {
37973e519524SHoward Hinnant        if (__comp(*__i, *__j))
37983e519524SHoward Hinnant        {
3799ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__i));
38003e519524SHoward Hinnant            _RandomAccessIterator __k = __j;
38013e519524SHoward Hinnant            __j = __i;
38023e519524SHoward Hinnant            do
38033e519524SHoward Hinnant            {
3804ce48a113SHoward Hinnant                *__j = _VSTD::move(*__k);
38053e519524SHoward Hinnant                __j = __k;
38063e519524SHoward Hinnant            } while (__j != __first && __comp(__t, *--__k));
3807ce48a113SHoward Hinnant            *__j = _VSTD::move(__t);
38083e519524SHoward Hinnant        }
38093e519524SHoward Hinnant        __j = __i;
38103e519524SHoward Hinnant    }
38113e519524SHoward Hinnant}
38123e519524SHoward Hinnant
38133e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
38143e519524SHoward Hinnantbool
38153e519524SHoward Hinnant__insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
38163e519524SHoward Hinnant{
38173e519524SHoward Hinnant    switch (__last - __first)
38183e519524SHoward Hinnant    {
38193e519524SHoward Hinnant    case 0:
38203e519524SHoward Hinnant    case 1:
38213e519524SHoward Hinnant        return true;
38223e519524SHoward Hinnant    case 2:
38233e519524SHoward Hinnant        if (__comp(*--__last, *__first))
38243e519524SHoward Hinnant            swap(*__first, *__last);
38253e519524SHoward Hinnant        return true;
38263e519524SHoward Hinnant    case 3:
3827ce48a113SHoward Hinnant        _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
38283e519524SHoward Hinnant        return true;
38293e519524SHoward Hinnant    case 4:
3830ce48a113SHoward Hinnant        _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
38313e519524SHoward Hinnant        return true;
38323e519524SHoward Hinnant    case 5:
3833ce48a113SHoward Hinnant        _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
38343e519524SHoward Hinnant        return true;
38353e519524SHoward Hinnant    }
38363e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
38373e519524SHoward Hinnant    _RandomAccessIterator __j = __first+2;
38383e519524SHoward Hinnant    __sort3<_Compare>(__first, __first+1, __j, __comp);
38393e519524SHoward Hinnant    const unsigned __limit = 8;
38403e519524SHoward Hinnant    unsigned __count = 0;
38413e519524SHoward Hinnant    for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
38423e519524SHoward Hinnant    {
38433e519524SHoward Hinnant        if (__comp(*__i, *__j))
38443e519524SHoward Hinnant        {
3845ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__i));
38463e519524SHoward Hinnant            _RandomAccessIterator __k = __j;
38473e519524SHoward Hinnant            __j = __i;
38483e519524SHoward Hinnant            do
38493e519524SHoward Hinnant            {
3850ce48a113SHoward Hinnant                *__j = _VSTD::move(*__k);
38513e519524SHoward Hinnant                __j = __k;
38523e519524SHoward Hinnant            } while (__j != __first && __comp(__t, *--__k));
3853ce48a113SHoward Hinnant            *__j = _VSTD::move(__t);
38543e519524SHoward Hinnant            if (++__count == __limit)
38553e519524SHoward Hinnant                return ++__i == __last;
38563e519524SHoward Hinnant        }
38573e519524SHoward Hinnant        __j = __i;
38583e519524SHoward Hinnant    }
38593e519524SHoward Hinnant    return true;
38603e519524SHoward Hinnant}
38613e519524SHoward Hinnant
38623e519524SHoward Hinnanttemplate <class _Compare, class _BirdirectionalIterator>
38633e519524SHoward Hinnantvoid
38643e519524SHoward Hinnant__insertion_sort_move(_BirdirectionalIterator __first1, _BirdirectionalIterator __last1,
38653e519524SHoward Hinnant                      typename iterator_traits<_BirdirectionalIterator>::value_type* __first2, _Compare __comp)
38663e519524SHoward Hinnant{
38673e519524SHoward Hinnant    typedef typename iterator_traits<_BirdirectionalIterator>::value_type value_type;
38683e519524SHoward Hinnant    if (__first1 != __last1)
38693e519524SHoward Hinnant    {
38703e519524SHoward Hinnant        __destruct_n __d(0);
38713e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h(__first2, __d);
38723e519524SHoward Hinnant        value_type* __last2 = __first2;
3873ce48a113SHoward Hinnant        ::new(__last2) value_type(_VSTD::move(*__first1));
38743e519524SHoward Hinnant        __d.__incr((value_type*)0);
38753e519524SHoward Hinnant        for (++__last2; ++__first1 != __last1; ++__last2)
38763e519524SHoward Hinnant        {
38773e519524SHoward Hinnant            value_type* __j2 = __last2;
38783e519524SHoward Hinnant            value_type* __i2 = __j2;
38793e519524SHoward Hinnant            if (__comp(*__first1, *--__i2))
38803e519524SHoward Hinnant            {
3881ce48a113SHoward Hinnant                ::new(__j2) value_type(_VSTD::move(*__i2));
38823e519524SHoward Hinnant                __d.__incr((value_type*)0);
38833e519524SHoward Hinnant                for (--__j2; __i2 != __first2 && __comp(*__first1,  *--__i2); --__j2)
3884ce48a113SHoward Hinnant                    *__j2 = _VSTD::move(*__i2);
3885ce48a113SHoward Hinnant                *__j2 = _VSTD::move(*__first1);
38863e519524SHoward Hinnant            }
38873e519524SHoward Hinnant            else
38883e519524SHoward Hinnant            {
3889ce48a113SHoward Hinnant                ::new(__j2) value_type(_VSTD::move(*__first1));
38903e519524SHoward Hinnant                __d.__incr((value_type*)0);
38913e519524SHoward Hinnant            }
38923e519524SHoward Hinnant        }
38933e519524SHoward Hinnant        __h.release();
38943e519524SHoward Hinnant    }
38953e519524SHoward Hinnant}
38963e519524SHoward Hinnant
38973e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
38983e519524SHoward Hinnantvoid
38993e519524SHoward Hinnant__sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
39003e519524SHoward Hinnant{
39013e519524SHoward Hinnant    // _Compare is known to be a reference type
39023e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
39033e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
3904ca740483SHoward Hinnant    const difference_type __limit = is_trivially_copy_constructible<value_type>::value &&
3905ca740483SHoward Hinnant                                    is_trivially_copy_assignable<value_type>::value ? 30 : 6;
39063e519524SHoward Hinnant    while (true)
39073e519524SHoward Hinnant    {
39083e519524SHoward Hinnant    __restart:
39093e519524SHoward Hinnant        difference_type __len = __last - __first;
39103e519524SHoward Hinnant        switch (__len)
39113e519524SHoward Hinnant        {
39123e519524SHoward Hinnant        case 0:
39133e519524SHoward Hinnant        case 1:
39143e519524SHoward Hinnant            return;
39153e519524SHoward Hinnant        case 2:
39163e519524SHoward Hinnant            if (__comp(*--__last, *__first))
39173e519524SHoward Hinnant                swap(*__first, *__last);
39183e519524SHoward Hinnant            return;
39193e519524SHoward Hinnant        case 3:
3920ce48a113SHoward Hinnant            _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
39213e519524SHoward Hinnant            return;
39223e519524SHoward Hinnant        case 4:
3923ce48a113SHoward Hinnant            _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
39243e519524SHoward Hinnant            return;
39253e519524SHoward Hinnant        case 5:
3926ce48a113SHoward Hinnant            _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
39273e519524SHoward Hinnant            return;
39283e519524SHoward Hinnant        }
39293e519524SHoward Hinnant        if (__len <= __limit)
39303e519524SHoward Hinnant        {
3931ce48a113SHoward Hinnant            _VSTD::__insertion_sort_3<_Compare>(__first, __last, __comp);
39323e519524SHoward Hinnant            return;
39333e519524SHoward Hinnant        }
39343e519524SHoward Hinnant        // __len > 5
39353e519524SHoward Hinnant        _RandomAccessIterator __m = __first;
39363e519524SHoward Hinnant        _RandomAccessIterator __lm1 = __last;
39373e519524SHoward Hinnant        --__lm1;
39383e519524SHoward Hinnant        unsigned __n_swaps;
39393e519524SHoward Hinnant        {
39403e519524SHoward Hinnant        difference_type __delta;
39413e519524SHoward Hinnant        if (__len >= 1000)
39423e519524SHoward Hinnant        {
39433e519524SHoward Hinnant            __delta = __len/2;
39443e519524SHoward Hinnant            __m += __delta;
39453e519524SHoward Hinnant            __delta /= 2;
3946ce48a113SHoward Hinnant            __n_swaps = _VSTD::__sort5<_Compare>(__first, __first + __delta, __m, __m+__delta, __lm1, __comp);
39473e519524SHoward Hinnant        }
39483e519524SHoward Hinnant        else
39493e519524SHoward Hinnant        {
39503e519524SHoward Hinnant            __delta = __len/2;
39513e519524SHoward Hinnant            __m += __delta;
3952ce48a113SHoward Hinnant            __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, __lm1, __comp);
39533e519524SHoward Hinnant        }
39543e519524SHoward Hinnant        }
39553e519524SHoward Hinnant        // *__m is median
39563e519524SHoward Hinnant        // partition [__first, __m) < *__m and *__m <= [__m, __last)
39573e519524SHoward Hinnant        // (this inhibits tossing elements equivalent to __m around unnecessarily)
39583e519524SHoward Hinnant        _RandomAccessIterator __i = __first;
39593e519524SHoward Hinnant        _RandomAccessIterator __j = __lm1;
39603e519524SHoward Hinnant        // j points beyond range to be tested, *__m is known to be <= *__lm1
39613e519524SHoward Hinnant        // The search going up is known to be guarded but the search coming down isn't.
39623e519524SHoward Hinnant        // Prime the downward search with a guard.
39633e519524SHoward Hinnant        if (!__comp(*__i, *__m))  // if *__first == *__m
39643e519524SHoward Hinnant        {
39653e519524SHoward Hinnant            // *__first == *__m, *__first doesn't go in first part
39663e519524SHoward Hinnant            // manually guard downward moving __j against __i
39673e519524SHoward Hinnant            while (true)
39683e519524SHoward Hinnant            {
39693e519524SHoward Hinnant                if (__i == --__j)
39703e519524SHoward Hinnant                {
39713e519524SHoward Hinnant                    // *__first == *__m, *__m <= all other elements
39723e519524SHoward Hinnant                    // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
39733e519524SHoward Hinnant                    ++__i;  // __first + 1
39743e519524SHoward Hinnant                    __j = __last;
39753e519524SHoward Hinnant                    if (!__comp(*__first, *--__j))  // we need a guard if *__first == *(__last-1)
39763e519524SHoward Hinnant                    {
39773e519524SHoward Hinnant                        while (true)
39783e519524SHoward Hinnant                        {
39793e519524SHoward Hinnant                            if (__i == __j)
39803e519524SHoward Hinnant                                return;  // [__first, __last) all equivalent elements
39813e519524SHoward Hinnant                            if (__comp(*__first, *__i))
39823e519524SHoward Hinnant                            {
39833e519524SHoward Hinnant                                swap(*__i, *__j);
39843e519524SHoward Hinnant                                ++__n_swaps;
39853e519524SHoward Hinnant                                ++__i;
39863e519524SHoward Hinnant                                break;
39873e519524SHoward Hinnant                            }
39883e519524SHoward Hinnant                            ++__i;
39893e519524SHoward Hinnant                        }
39903e519524SHoward Hinnant                    }
39913e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
39923e519524SHoward Hinnant                    if (__i == __j)
39933e519524SHoward Hinnant                        return;
39943e519524SHoward Hinnant                    while (true)
39953e519524SHoward Hinnant                    {
39963e519524SHoward Hinnant                        while (!__comp(*__first, *__i))
39973e519524SHoward Hinnant                            ++__i;
39983e519524SHoward Hinnant                        while (__comp(*__first, *--__j))
39993e519524SHoward Hinnant                            ;
40003e519524SHoward Hinnant                        if (__i >= __j)
40013e519524SHoward Hinnant                            break;
40023e519524SHoward Hinnant                        swap(*__i, *__j);
40033e519524SHoward Hinnant                        ++__n_swaps;
40043e519524SHoward Hinnant                        ++__i;
40053e519524SHoward Hinnant                    }
40063e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__i, __last)
40073e519524SHoward Hinnant                    // The first part is sorted, sort the secod part
4008ce48a113SHoward Hinnant                    // _VSTD::__sort<_Compare>(__i, __last, __comp);
40093e519524SHoward Hinnant                    __first = __i;
40103e519524SHoward Hinnant                    goto __restart;
40113e519524SHoward Hinnant                }
40123e519524SHoward Hinnant                if (__comp(*__j, *__m))
40133e519524SHoward Hinnant                {
40143e519524SHoward Hinnant                    swap(*__i, *__j);
40153e519524SHoward Hinnant                    ++__n_swaps;
40163e519524SHoward Hinnant                    break;  // found guard for downward moving __j, now use unguarded partition
40173e519524SHoward Hinnant                }
40183e519524SHoward Hinnant            }
40193e519524SHoward Hinnant        }
40203e519524SHoward Hinnant        // It is known that *__i < *__m
40213e519524SHoward Hinnant        ++__i;
40223e519524SHoward Hinnant        // j points beyond range to be tested, *__m is known to be <= *__lm1
40233e519524SHoward Hinnant        // if not yet partitioned...
40243e519524SHoward Hinnant        if (__i < __j)
40253e519524SHoward Hinnant        {
40263e519524SHoward Hinnant            // known that *(__i - 1) < *__m
40273e519524SHoward Hinnant            // known that __i <= __m
40283e519524SHoward Hinnant            while (true)
40293e519524SHoward Hinnant            {
40303e519524SHoward Hinnant                // __m still guards upward moving __i
40313e519524SHoward Hinnant                while (__comp(*__i, *__m))
40323e519524SHoward Hinnant                    ++__i;
40333e519524SHoward Hinnant                // It is now known that a guard exists for downward moving __j
40343e519524SHoward Hinnant                while (!__comp(*--__j, *__m))
40353e519524SHoward Hinnant                    ;
40363e519524SHoward Hinnant                if (__i > __j)
40373e519524SHoward Hinnant                    break;
40383e519524SHoward Hinnant                swap(*__i, *__j);
40393e519524SHoward Hinnant                ++__n_swaps;
40403e519524SHoward Hinnant                // It is known that __m != __j
40413e519524SHoward Hinnant                // If __m just moved, follow it
40423e519524SHoward Hinnant                if (__m == __i)
40433e519524SHoward Hinnant                    __m = __j;
40443e519524SHoward Hinnant                ++__i;
40453e519524SHoward Hinnant            }
40463e519524SHoward Hinnant        }
40473e519524SHoward Hinnant        // [__first, __i) < *__m and *__m <= [__i, __last)
40483e519524SHoward Hinnant        if (__i != __m && __comp(*__m, *__i))
40493e519524SHoward Hinnant        {
40503e519524SHoward Hinnant            swap(*__i, *__m);
40513e519524SHoward Hinnant            ++__n_swaps;
40523e519524SHoward Hinnant        }
40533e519524SHoward Hinnant        // [__first, __i) < *__i and *__i <= [__i+1, __last)
40543e519524SHoward Hinnant        // If we were given a perfect partition, see if insertion sort is quick...
40553e519524SHoward Hinnant        if (__n_swaps == 0)
40563e519524SHoward Hinnant        {
4057ce48a113SHoward Hinnant            bool __fs = _VSTD::__insertion_sort_incomplete<_Compare>(__first, __i, __comp);
4058ce48a113SHoward Hinnant            if (_VSTD::__insertion_sort_incomplete<_Compare>(__i+1, __last, __comp))
40593e519524SHoward Hinnant            {
40603e519524SHoward Hinnant                if (__fs)
40613e519524SHoward Hinnant                    return;
40623e519524SHoward Hinnant                __last = __i;
40633e519524SHoward Hinnant                continue;
40643e519524SHoward Hinnant            }
40653e519524SHoward Hinnant            else
40663e519524SHoward Hinnant            {
40673e519524SHoward Hinnant                if (__fs)
40683e519524SHoward Hinnant                {
40693e519524SHoward Hinnant                    __first = ++__i;
40703e519524SHoward Hinnant                    continue;
40713e519524SHoward Hinnant                }
40723e519524SHoward Hinnant            }
40733e519524SHoward Hinnant        }
40743e519524SHoward Hinnant        // sort smaller range with recursive call and larger with tail recursion elimination
40753e519524SHoward Hinnant        if (__i - __first < __last - __i)
40763e519524SHoward Hinnant        {
4077ce48a113SHoward Hinnant            _VSTD::__sort<_Compare>(__first, __i, __comp);
4078ce48a113SHoward Hinnant            // _VSTD::__sort<_Compare>(__i+1, __last, __comp);
40793e519524SHoward Hinnant            __first = ++__i;
40803e519524SHoward Hinnant        }
40813e519524SHoward Hinnant        else
40823e519524SHoward Hinnant        {
4083ce48a113SHoward Hinnant            _VSTD::__sort<_Compare>(__i+1, __last, __comp);
4084ce48a113SHoward Hinnant            // _VSTD::__sort<_Compare>(__first, __i, __comp);
40853e519524SHoward Hinnant            __last = __i;
40863e519524SHoward Hinnant        }
40873e519524SHoward Hinnant    }
40883e519524SHoward Hinnant}
40893e519524SHoward Hinnant
40903e519524SHoward Hinnant// This forwarder keeps the top call and the recursive calls using the same instantiation, forcing a reference _Compare
40913e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
40923e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
40933e519524SHoward Hinnantvoid
40943e519524SHoward Hinnantsort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
40953e519524SHoward Hinnant{
4096aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4097aa1cad15SEric Fiselier    _VSTD::__sort<_Comp_ref>(__first, __last, _Comp_ref(__comp));
40983e519524SHoward Hinnant}
40993e519524SHoward Hinnant
41003e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
41013e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41023e519524SHoward Hinnantvoid
41033e519524SHoward Hinnantsort(_RandomAccessIterator __first, _RandomAccessIterator __last)
41043e519524SHoward Hinnant{
4105ce48a113SHoward Hinnant    _VSTD::sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
41063e519524SHoward Hinnant}
41073e519524SHoward Hinnant
41083e519524SHoward Hinnanttemplate <class _Tp>
41093e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41103e519524SHoward Hinnantvoid
41113e519524SHoward Hinnantsort(_Tp** __first, _Tp** __last)
41123e519524SHoward Hinnant{
4113ce48a113SHoward Hinnant    _VSTD::sort((size_t*)__first, (size_t*)__last, __less<size_t>());
41143e519524SHoward Hinnant}
41153e519524SHoward Hinnant
41163e519524SHoward Hinnanttemplate <class _Tp>
41173e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
41183e519524SHoward Hinnantvoid
41193e519524SHoward Hinnantsort(__wrap_iter<_Tp*> __first, __wrap_iter<_Tp*> __last)
41203e519524SHoward Hinnant{
4121ce48a113SHoward Hinnant    _VSTD::sort(__first.base(), __last.base());
41223e519524SHoward Hinnant}
41233e519524SHoward Hinnant
4124f554add5SHoward Hinnanttemplate <class _Tp, class _Compare>
4125f554add5SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
4126f554add5SHoward Hinnantvoid
4127f554add5SHoward Hinnantsort(__wrap_iter<_Tp*> __first, __wrap_iter<_Tp*> __last, _Compare __comp)
4128f554add5SHoward Hinnant{
4129f554add5SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4130f554add5SHoward Hinnant    _VSTD::sort<_Tp*, _Comp_ref>(__first.base(), __last.base(), __comp);
4131f554add5SHoward Hinnant}
4132f554add5SHoward Hinnant
4133f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<char>&, char*>(char*, char*, __less<char>&))
4134f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
4135f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
4136f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
4137f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<short>&, short*>(short*, short*, __less<short>&))
4138f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
4139f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<int>&, int*>(int*, int*, __less<int>&))
4140f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
4141f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long>&, long*>(long*, long*, __less<long>&))
4142f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
4143f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
4144f0544c20SHoward 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>&))
4145f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<float>&, float*>(float*, float*, __less<float>&))
4146f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<double>&, double*>(double*, double*, __less<double>&))
4147f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
41483e519524SHoward Hinnant
4149f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<char>&, char*>(char*, char*, __less<char>&))
4150f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
4151f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
4152f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
4153f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<short>&, short*>(short*, short*, __less<short>&))
4154f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
4155f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<int>&, int*>(int*, int*, __less<int>&))
4156f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
4157f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long>&, long*>(long*, long*, __less<long>&))
4158f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
4159f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
4160f0544c20SHoward 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>&))
4161f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<float>&, float*>(float*, float*, __less<float>&))
4162f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<double>&, double*>(double*, double*, __less<double>&))
4163f0544c20SHoward Hinnant_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
41643e519524SHoward Hinnant
4165f0544c20SHoward 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>&))
41663e519524SHoward Hinnant
41673e519524SHoward Hinnant// lower_bound
41683e519524SHoward Hinnant
41693e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4170d57c03ddSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
4171e4383379SHoward Hinnant__lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
41723e519524SHoward Hinnant{
41733e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4174ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
41753e519524SHoward Hinnant    while (__len != 0)
41763e519524SHoward Hinnant    {
417704695a75SLouis Dionne        difference_type __l2 = _VSTD::__half_positive(__len);
41783e519524SHoward Hinnant        _ForwardIterator __m = __first;
4179ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
4180e4383379SHoward Hinnant        if (__comp(*__m, __value_))
41813e519524SHoward Hinnant        {
41823e519524SHoward Hinnant            __first = ++__m;
41833e519524SHoward Hinnant            __len -= __l2 + 1;
41843e519524SHoward Hinnant        }
41853e519524SHoward Hinnant        else
41863e519524SHoward Hinnant            __len = __l2;
41873e519524SHoward Hinnant    }
41883e519524SHoward Hinnant    return __first;
41893e519524SHoward Hinnant}
41903e519524SHoward Hinnant
41913e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
41921362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
41931362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
41943e519524SHoward Hinnant_ForwardIterator
4195e4383379SHoward Hinnantlower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
41963e519524SHoward Hinnant{
41973e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4198e4383379SHoward Hinnant    return __lower_bound<_Comp_ref>(__first, __last, __value_, __comp);
41993e519524SHoward Hinnant}
42003e519524SHoward Hinnant
42013e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
42021362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
42031362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42043e519524SHoward Hinnant_ForwardIterator
4205e4383379SHoward Hinnantlower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
42063e519524SHoward Hinnant{
4207e4383379SHoward Hinnant    return _VSTD::lower_bound(__first, __last, __value_,
42083e519524SHoward Hinnant                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
42093e519524SHoward Hinnant}
42103e519524SHoward Hinnant
42113e519524SHoward Hinnant// upper_bound
42123e519524SHoward Hinnant
42133e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4214d57c03ddSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
4215e4383379SHoward Hinnant__upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42163e519524SHoward Hinnant{
42173e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4218ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
42193e519524SHoward Hinnant    while (__len != 0)
42203e519524SHoward Hinnant    {
422104695a75SLouis Dionne        difference_type __l2 = _VSTD::__half_positive(__len);
42223e519524SHoward Hinnant        _ForwardIterator __m = __first;
4223ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
4224e4383379SHoward Hinnant        if (__comp(__value_, *__m))
42253e519524SHoward Hinnant            __len = __l2;
42263e519524SHoward Hinnant        else
42273e519524SHoward Hinnant        {
42283e519524SHoward Hinnant            __first = ++__m;
42293e519524SHoward Hinnant            __len -= __l2 + 1;
42303e519524SHoward Hinnant        }
42313e519524SHoward Hinnant    }
42323e519524SHoward Hinnant    return __first;
42333e519524SHoward Hinnant}
42343e519524SHoward Hinnant
42353e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
42361362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
42371362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42383e519524SHoward Hinnant_ForwardIterator
4239e4383379SHoward Hinnantupper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42403e519524SHoward Hinnant{
42413e519524SHoward Hinnant    typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
4242e4383379SHoward Hinnant    return __upper_bound<_Comp_ref>(__first, __last, __value_, __comp);
42433e519524SHoward Hinnant}
42443e519524SHoward Hinnant
42453e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
42461362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
42471362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42483e519524SHoward Hinnant_ForwardIterator
4249e4383379SHoward Hinnantupper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
42503e519524SHoward Hinnant{
4251e4383379SHoward Hinnant    return _VSTD::upper_bound(__first, __last, __value_,
42523e519524SHoward Hinnant                             __less<_Tp, typename iterator_traits<_ForwardIterator>::value_type>());
42533e519524SHoward Hinnant}
42543e519524SHoward Hinnant
42553e519524SHoward Hinnant// equal_range
42563e519524SHoward Hinnant
42573e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4258d57c03ddSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_ForwardIterator, _ForwardIterator>
4259e4383379SHoward Hinnant__equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42603e519524SHoward Hinnant{
42613e519524SHoward Hinnant    typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
4262ce48a113SHoward Hinnant    difference_type __len = _VSTD::distance(__first, __last);
42633e519524SHoward Hinnant    while (__len != 0)
42643e519524SHoward Hinnant    {
426504695a75SLouis Dionne        difference_type __l2 = _VSTD::__half_positive(__len);
42663e519524SHoward Hinnant        _ForwardIterator __m = __first;
4267ce48a113SHoward Hinnant        _VSTD::advance(__m, __l2);
4268e4383379SHoward Hinnant        if (__comp(*__m, __value_))
42693e519524SHoward Hinnant        {
42703e519524SHoward Hinnant            __first = ++__m;
42713e519524SHoward Hinnant            __len -= __l2 + 1;
42723e519524SHoward Hinnant        }
4273e4383379SHoward Hinnant        else if (__comp(__value_, *__m))
42743e519524SHoward Hinnant        {
42753e519524SHoward Hinnant            __last = __m;
42763e519524SHoward Hinnant            __len = __l2;
42773e519524SHoward Hinnant        }
42783e519524SHoward Hinnant        else
42793e519524SHoward Hinnant        {
42803e519524SHoward Hinnant            _ForwardIterator __mp1 = __m;
42813e519524SHoward Hinnant            return pair<_ForwardIterator, _ForwardIterator>
42823e519524SHoward Hinnant                   (
4283e4383379SHoward Hinnant                      __lower_bound<_Compare>(__first, __m, __value_, __comp),
4284e4383379SHoward Hinnant                      __upper_bound<_Compare>(++__mp1, __last, __value_, __comp)
42853e519524SHoward Hinnant                   );
42863e519524SHoward Hinnant        }
42873e519524SHoward Hinnant    }
42883e519524SHoward Hinnant    return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
42893e519524SHoward Hinnant}
42903e519524SHoward Hinnant
42913e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
42921362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
42931362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
42943e519524SHoward Hinnantpair<_ForwardIterator, _ForwardIterator>
4295e4383379SHoward Hinnantequal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
42963e519524SHoward Hinnant{
4297aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4298e4383379SHoward Hinnant    return __equal_range<_Comp_ref>(__first, __last, __value_, __comp);
42993e519524SHoward Hinnant}
43003e519524SHoward Hinnant
43013e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
43021362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
43031362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43043e519524SHoward Hinnantpair<_ForwardIterator, _ForwardIterator>
4305e4383379SHoward Hinnantequal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
43063e519524SHoward Hinnant{
4307e4383379SHoward Hinnant    return _VSTD::equal_range(__first, __last, __value_,
43083e519524SHoward Hinnant                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43093e519524SHoward Hinnant}
43103e519524SHoward Hinnant
43113e519524SHoward Hinnant// binary_search
43123e519524SHoward Hinnant
43133e519524SHoward Hinnanttemplate <class _Compare, class _ForwardIterator, class _Tp>
4314d57c03ddSMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43153e519524SHoward Hinnantbool
4316e4383379SHoward Hinnant__binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43173e519524SHoward Hinnant{
4318e4383379SHoward Hinnant    __first = __lower_bound<_Compare>(__first, __last, __value_, __comp);
4319e4383379SHoward Hinnant    return __first != __last && !__comp(__value_, *__first);
43203e519524SHoward Hinnant}
43213e519524SHoward Hinnant
43223e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp, class _Compare>
43231362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
43241362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43253e519524SHoward Hinnantbool
4326e4383379SHoward Hinnantbinary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
43273e519524SHoward Hinnant{
4328aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4329e4383379SHoward Hinnant    return __binary_search<_Comp_ref>(__first, __last, __value_, __comp);
43303e519524SHoward Hinnant}
43313e519524SHoward Hinnant
43323e519524SHoward Hinnanttemplate <class _ForwardIterator, class _Tp>
43331362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
43341362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
43353e519524SHoward Hinnantbool
4336e4383379SHoward Hinnantbinary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
43373e519524SHoward Hinnant{
4338e4383379SHoward Hinnant    return _VSTD::binary_search(__first, __last, __value_,
43393e519524SHoward Hinnant                             __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
43403e519524SHoward Hinnant}
43413e519524SHoward Hinnant
43423e519524SHoward Hinnant// merge
43433e519524SHoward Hinnant
43443e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
43453e519524SHoward Hinnant_OutputIterator
43463e519524SHoward Hinnant__merge(_InputIterator1 __first1, _InputIterator1 __last1,
43473e519524SHoward Hinnant        _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
43483e519524SHoward Hinnant{
43493e519524SHoward Hinnant    for (; __first1 != __last1; ++__result)
43503e519524SHoward Hinnant    {
43513e519524SHoward Hinnant        if (__first2 == __last2)
4352ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
43533e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
43543e519524SHoward Hinnant        {
43553e519524SHoward Hinnant            *__result = *__first2;
43563e519524SHoward Hinnant            ++__first2;
43573e519524SHoward Hinnant        }
43583e519524SHoward Hinnant        else
43593e519524SHoward Hinnant        {
43603e519524SHoward Hinnant            *__result = *__first1;
43613e519524SHoward Hinnant            ++__first1;
43623e519524SHoward Hinnant        }
43633e519524SHoward Hinnant    }
4364ce48a113SHoward Hinnant    return _VSTD::copy(__first2, __last2, __result);
43653e519524SHoward Hinnant}
43663e519524SHoward Hinnant
43673e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
43683e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
43693e519524SHoward Hinnant_OutputIterator
43703e519524SHoward Hinnantmerge(_InputIterator1 __first1, _InputIterator1 __last1,
43713e519524SHoward Hinnant      _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
43723e519524SHoward Hinnant{
4373aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4374ce48a113SHoward Hinnant    return _VSTD::__merge<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
43753e519524SHoward Hinnant}
43763e519524SHoward Hinnant
43773e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
43783e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
43793e519524SHoward Hinnant_OutputIterator
43803e519524SHoward Hinnantmerge(_InputIterator1 __first1, _InputIterator1 __last1,
43813e519524SHoward Hinnant      _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
43823e519524SHoward Hinnant{
43833e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type __v1;
43843e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator2>::value_type __v2;
43853e519524SHoward Hinnant    return merge(__first1, __last1, __first2, __last2, __result, __less<__v1, __v2>());
43863e519524SHoward Hinnant}
43873e519524SHoward Hinnant
43883e519524SHoward Hinnant// inplace_merge
43893e519524SHoward Hinnant
4390adfdae18SMarshall Clowtemplate <class _Compare, class _InputIterator1, class _InputIterator2,
4391adfdae18SMarshall Clow          class _OutputIterator>
4392adfdae18SMarshall Clowvoid __half_inplace_merge(_InputIterator1 __first1, _InputIterator1 __last1,
4393adfdae18SMarshall Clow                          _InputIterator2 __first2, _InputIterator2 __last2,
4394adfdae18SMarshall Clow                          _OutputIterator __result, _Compare __comp)
4395adfdae18SMarshall Clow{
4396adfdae18SMarshall Clow    for (; __first1 != __last1; ++__result)
4397adfdae18SMarshall Clow    {
4398adfdae18SMarshall Clow        if (__first2 == __last2)
4399adfdae18SMarshall Clow        {
4400adfdae18SMarshall Clow            _VSTD::move(__first1, __last1, __result);
4401adfdae18SMarshall Clow            return;
4402adfdae18SMarshall Clow        }
4403adfdae18SMarshall Clow
4404adfdae18SMarshall Clow        if (__comp(*__first2, *__first1))
4405adfdae18SMarshall Clow        {
4406adfdae18SMarshall Clow            *__result = _VSTD::move(*__first2);
4407adfdae18SMarshall Clow            ++__first2;
4408adfdae18SMarshall Clow        }
4409adfdae18SMarshall Clow        else
4410adfdae18SMarshall Clow        {
4411adfdae18SMarshall Clow            *__result = _VSTD::move(*__first1);
4412adfdae18SMarshall Clow            ++__first1;
4413adfdae18SMarshall Clow        }
4414adfdae18SMarshall Clow    }
4415adfdae18SMarshall Clow    // __first2 through __last2 are already in the right spot.
4416adfdae18SMarshall Clow}
4417adfdae18SMarshall Clow
44183e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
44193e519524SHoward Hinnantvoid
44203e519524SHoward Hinnant__buffered_inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
44213e519524SHoward Hinnant                _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
44223e519524SHoward Hinnant                                 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
44233e519524SHoward Hinnant                typename iterator_traits<_BidirectionalIterator>::value_type* __buff)
44243e519524SHoward Hinnant{
44253e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
44263e519524SHoward Hinnant    __destruct_n __d(0);
44273e519524SHoward Hinnant    unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
44283e519524SHoward Hinnant    if (__len1 <= __len2)
44293e519524SHoward Hinnant    {
44303e519524SHoward Hinnant        value_type* __p = __buff;
4431*7fa68653SMarshall Clow        for (_BidirectionalIterator __i = __first; __i != __middle; __d.__incr((value_type*)0), (void) ++__i, (void) ++__p)
4432ce48a113SHoward Hinnant            ::new(__p) value_type(_VSTD::move(*__i));
4433adfdae18SMarshall Clow        __half_inplace_merge(__buff, __p, __middle, __last, __first, __comp);
44343e519524SHoward Hinnant    }
44353e519524SHoward Hinnant    else
44363e519524SHoward Hinnant    {
44373e519524SHoward Hinnant        value_type* __p = __buff;
4438*7fa68653SMarshall Clow        for (_BidirectionalIterator __i = __middle; __i != __last; __d.__incr((value_type*)0), (void) ++__i, (void) ++__p)
4439ce48a113SHoward Hinnant            ::new(__p) value_type(_VSTD::move(*__i));
44403e519524SHoward Hinnant        typedef reverse_iterator<_BidirectionalIterator> _RBi;
44413e519524SHoward Hinnant        typedef reverse_iterator<value_type*> _Rv;
4442adfdae18SMarshall Clow        __half_inplace_merge(_Rv(__p), _Rv(__buff),
4443adfdae18SMarshall Clow                             _RBi(__middle), _RBi(__first),
4444a763b36fSMarshall Clow                             _RBi(__last), __invert<_Compare>(__comp));
44453e519524SHoward Hinnant    }
44463e519524SHoward Hinnant}
44473e519524SHoward Hinnant
44483e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
44493e519524SHoward Hinnantvoid
44503e519524SHoward Hinnant__inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
44513e519524SHoward Hinnant                _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
44523e519524SHoward Hinnant                                 typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
44533e519524SHoward Hinnant                typename iterator_traits<_BidirectionalIterator>::value_type* __buff, ptrdiff_t __buff_size)
44543e519524SHoward Hinnant{
44553e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
44563e519524SHoward Hinnant    while (true)
44573e519524SHoward Hinnant    {
44583e519524SHoward Hinnant        // if __middle == __last, we're done
44593e519524SHoward Hinnant        if (__len2 == 0)
44603e519524SHoward Hinnant            return;
4461526e0929SMarshall Clow        if (__len1 <= __buff_size || __len2 <= __buff_size)
4462526e0929SMarshall Clow            return __buffered_inplace_merge<_Compare>
4463526e0929SMarshall Clow                   (__first, __middle, __last, __comp, __len1, __len2, __buff);
44643e519524SHoward Hinnant        // shrink [__first, __middle) as much as possible (with no moves), returning if it shrinks to 0
4465910285b2SEric Fiselier        for (; true; ++__first, (void) --__len1)
44663e519524SHoward Hinnant        {
44673e519524SHoward Hinnant            if (__len1 == 0)
44683e519524SHoward Hinnant                return;
44693e519524SHoward Hinnant            if (__comp(*__middle, *__first))
44703e519524SHoward Hinnant                break;
44713e519524SHoward Hinnant        }
44723e519524SHoward Hinnant        // __first < __middle < __last
44733e519524SHoward Hinnant        // *__first > *__middle
44743e519524SHoward Hinnant        // partition [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last) such that
44753e519524SHoward Hinnant        //     all elements in:
44763e519524SHoward Hinnant        //         [__first, __m1)  <= [__middle, __m2)
44773e519524SHoward Hinnant        //         [__middle, __m2) <  [__m1, __middle)
44783e519524SHoward Hinnant        //         [__m1, __middle) <= [__m2, __last)
44793e519524SHoward Hinnant        //     and __m1 or __m2 is in the middle of its range
44803e519524SHoward Hinnant        _BidirectionalIterator __m1;  // "median" of [__first, __middle)
44813e519524SHoward Hinnant        _BidirectionalIterator __m2;  // "median" of [__middle, __last)
44823e519524SHoward Hinnant        difference_type __len11;      // distance(__first, __m1)
44833e519524SHoward Hinnant        difference_type __len21;      // distance(__middle, __m2)
44843e519524SHoward Hinnant        // binary search smaller range
44853e519524SHoward Hinnant        if (__len1 < __len2)
44863e519524SHoward Hinnant        {   // __len >= 1, __len2 >= 2
44873e519524SHoward Hinnant            __len21 = __len2 / 2;
44883e519524SHoward Hinnant            __m2 = __middle;
4489ce48a113SHoward Hinnant            _VSTD::advance(__m2, __len21);
44903e519524SHoward Hinnant            __m1 = __upper_bound<_Compare>(__first, __middle, *__m2, __comp);
4491ce48a113SHoward Hinnant            __len11 = _VSTD::distance(__first, __m1);
44923e519524SHoward Hinnant        }
44933e519524SHoward Hinnant        else
44943e519524SHoward Hinnant        {
44953e519524SHoward Hinnant            if (__len1 == 1)
44963e519524SHoward Hinnant            {   // __len1 >= __len2 && __len2 > 0, therefore __len2 == 1
44973e519524SHoward Hinnant                // It is known *__first > *__middle
44983e519524SHoward Hinnant                swap(*__first, *__middle);
44993e519524SHoward Hinnant                return;
45003e519524SHoward Hinnant            }
45013e519524SHoward Hinnant            // __len1 >= 2, __len2 >= 1
45023e519524SHoward Hinnant            __len11 = __len1 / 2;
45033e519524SHoward Hinnant            __m1 = __first;
4504ce48a113SHoward Hinnant            _VSTD::advance(__m1, __len11);
45053e519524SHoward Hinnant            __m2 = __lower_bound<_Compare>(__middle, __last, *__m1, __comp);
4506ce48a113SHoward Hinnant            __len21 = _VSTD::distance(__middle, __m2);
45073e519524SHoward Hinnant        }
45083e519524SHoward Hinnant        difference_type __len12 = __len1 - __len11;  // distance(__m1, __middle)
45093e519524SHoward Hinnant        difference_type __len22 = __len2 - __len21;  // distance(__m2, __last)
45103e519524SHoward Hinnant        // [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last)
45113e519524SHoward Hinnant        // swap middle two partitions
4512ce48a113SHoward Hinnant        __middle = _VSTD::rotate(__m1, __middle, __m2);
45133e519524SHoward Hinnant        // __len12 and __len21 now have swapped meanings
45143e519524SHoward Hinnant        // merge smaller range with recurisve call and larger with tail recursion elimination
45153e519524SHoward Hinnant        if (__len11 + __len21 < __len12 + __len22)
45163e519524SHoward Hinnant        {
45173e519524SHoward Hinnant            __inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
45183e519524SHoward Hinnant//          __inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
45193e519524SHoward Hinnant            __first = __middle;
45203e519524SHoward Hinnant            __middle = __m2;
45213e519524SHoward Hinnant            __len1 = __len12;
45223e519524SHoward Hinnant            __len2 = __len22;
45233e519524SHoward Hinnant        }
45243e519524SHoward Hinnant        else
45253e519524SHoward Hinnant        {
45263e519524SHoward Hinnant            __inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
45273e519524SHoward Hinnant//          __inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
45283e519524SHoward Hinnant            __last = __middle;
45293e519524SHoward Hinnant            __middle = __m1;
45303e519524SHoward Hinnant            __len1 = __len11;
45313e519524SHoward Hinnant            __len2 = __len21;
45323e519524SHoward Hinnant        }
45333e519524SHoward Hinnant    }
45343e519524SHoward Hinnant}
45353e519524SHoward Hinnant
45363e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _Compare>
45373e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
45383e519524SHoward Hinnantvoid
45393e519524SHoward Hinnantinplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
45403e519524SHoward Hinnant              _Compare __comp)
45413e519524SHoward Hinnant{
45423e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
45433e519524SHoward Hinnant    typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
4544ce48a113SHoward Hinnant    difference_type __len1 = _VSTD::distance(__first, __middle);
4545ce48a113SHoward Hinnant    difference_type __len2 = _VSTD::distance(__middle, __last);
4546ce48a113SHoward Hinnant    difference_type __buf_size = _VSTD::min(__len1, __len2);
45470b48cf9aSMarshall Clow    pair<value_type*, ptrdiff_t> __buf = _VSTD::get_temporary_buffer<value_type>(__buf_size);
45480b48cf9aSMarshall Clow    unique_ptr<value_type, __return_temporary_buffer> __h(__buf.first);
4549aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
4550ce48a113SHoward Hinnant    return _VSTD::__inplace_merge<_Comp_ref>(__first, __middle, __last, __comp, __len1, __len2,
45513e519524SHoward Hinnant                                            __buf.first, __buf.second);
45523e519524SHoward Hinnant}
45533e519524SHoward Hinnant
45543e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
45553e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
45563e519524SHoward Hinnantvoid
45573e519524SHoward Hinnantinplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last)
45583e519524SHoward Hinnant{
4559ce48a113SHoward Hinnant    _VSTD::inplace_merge(__first, __middle, __last,
45603e519524SHoward Hinnant                        __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
45613e519524SHoward Hinnant}
45623e519524SHoward Hinnant
45633e519524SHoward Hinnant// stable_sort
45643e519524SHoward Hinnant
45653e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2>
45663e519524SHoward Hinnantvoid
45673e519524SHoward Hinnant__merge_move_construct(_InputIterator1 __first1, _InputIterator1 __last1,
45683e519524SHoward Hinnant        _InputIterator2 __first2, _InputIterator2 __last2,
45693e519524SHoward Hinnant        typename iterator_traits<_InputIterator1>::value_type* __result, _Compare __comp)
45703e519524SHoward Hinnant{
45713e519524SHoward Hinnant    typedef typename iterator_traits<_InputIterator1>::value_type value_type;
45723e519524SHoward Hinnant    __destruct_n __d(0);
45733e519524SHoward Hinnant    unique_ptr<value_type, __destruct_n&> __h(__result, __d);
45743e519524SHoward Hinnant    for (; true; ++__result)
45753e519524SHoward Hinnant    {
45763e519524SHoward Hinnant        if (__first1 == __last1)
45773e519524SHoward Hinnant        {
4578*7fa68653SMarshall Clow            for (; __first2 != __last2; ++__first2, ++__result, (void) __d.__incr((value_type*)0))
4579ce48a113SHoward Hinnant                ::new (__result) value_type(_VSTD::move(*__first2));
45803e519524SHoward Hinnant            __h.release();
45813e519524SHoward Hinnant            return;
45823e519524SHoward Hinnant        }
45833e519524SHoward Hinnant        if (__first2 == __last2)
45843e519524SHoward Hinnant        {
4585*7fa68653SMarshall Clow            for (; __first1 != __last1; ++__first1, ++__result, (void) __d.__incr((value_type*)0))
4586ce48a113SHoward Hinnant                ::new (__result) value_type(_VSTD::move(*__first1));
45873e519524SHoward Hinnant            __h.release();
45883e519524SHoward Hinnant            return;
45893e519524SHoward Hinnant        }
45903e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
45913e519524SHoward Hinnant        {
4592ce48a113SHoward Hinnant            ::new (__result) value_type(_VSTD::move(*__first2));
45933e519524SHoward Hinnant            __d.__incr((value_type*)0);
45943e519524SHoward Hinnant            ++__first2;
45953e519524SHoward Hinnant        }
45963e519524SHoward Hinnant        else
45973e519524SHoward Hinnant        {
4598ce48a113SHoward Hinnant            ::new (__result) value_type(_VSTD::move(*__first1));
45993e519524SHoward Hinnant            __d.__incr((value_type*)0);
46003e519524SHoward Hinnant            ++__first1;
46013e519524SHoward Hinnant        }
46023e519524SHoward Hinnant    }
46033e519524SHoward Hinnant}
46043e519524SHoward Hinnant
46053e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
46063e519524SHoward Hinnantvoid
46073e519524SHoward Hinnant__merge_move_assign(_InputIterator1 __first1, _InputIterator1 __last1,
46083e519524SHoward Hinnant        _InputIterator2 __first2, _InputIterator2 __last2,
46093e519524SHoward Hinnant        _OutputIterator __result, _Compare __comp)
46103e519524SHoward Hinnant{
46113e519524SHoward Hinnant    for (; __first1 != __last1; ++__result)
46123e519524SHoward Hinnant    {
46133e519524SHoward Hinnant        if (__first2 == __last2)
46143e519524SHoward Hinnant        {
4615*7fa68653SMarshall Clow            for (; __first1 != __last1; ++__first1, (void) ++__result)
4616ce48a113SHoward Hinnant                *__result = _VSTD::move(*__first1);
46173e519524SHoward Hinnant            return;
46183e519524SHoward Hinnant        }
46193e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
46203e519524SHoward Hinnant        {
4621ce48a113SHoward Hinnant            *__result = _VSTD::move(*__first2);
46223e519524SHoward Hinnant            ++__first2;
46233e519524SHoward Hinnant        }
46243e519524SHoward Hinnant        else
46253e519524SHoward Hinnant        {
4626ce48a113SHoward Hinnant            *__result = _VSTD::move(*__first1);
46273e519524SHoward Hinnant            ++__first1;
46283e519524SHoward Hinnant        }
46293e519524SHoward Hinnant    }
4630*7fa68653SMarshall Clow    for (; __first2 != __last2; ++__first2, (void) ++__result)
4631ce48a113SHoward Hinnant        *__result = _VSTD::move(*__first2);
46323e519524SHoward Hinnant}
46333e519524SHoward Hinnant
46343e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
46353e519524SHoward Hinnantvoid
46363e519524SHoward Hinnant__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
46373e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46383e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size);
46393e519524SHoward Hinnant
46403e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
46413e519524SHoward Hinnantvoid
46423e519524SHoward Hinnant__stable_sort_move(_RandomAccessIterator __first1, _RandomAccessIterator __last1, _Compare __comp,
46433e519524SHoward Hinnant                   typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46443e519524SHoward Hinnant                   typename iterator_traits<_RandomAccessIterator>::value_type* __first2)
46453e519524SHoward Hinnant{
46463e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
46473e519524SHoward Hinnant    switch (__len)
46483e519524SHoward Hinnant    {
46493e519524SHoward Hinnant    case 0:
46503e519524SHoward Hinnant        return;
46513e519524SHoward Hinnant    case 1:
4652ce48a113SHoward Hinnant        ::new(__first2) value_type(_VSTD::move(*__first1));
46533e519524SHoward Hinnant        return;
46543e519524SHoward Hinnant    case 2:
46553e519524SHoward Hinnant        __destruct_n __d(0);
46563e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h2(__first2, __d);
46573e519524SHoward Hinnant        if (__comp(*--__last1, *__first1))
46583e519524SHoward Hinnant        {
4659ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__last1));
46603e519524SHoward Hinnant            __d.__incr((value_type*)0);
46613e519524SHoward Hinnant            ++__first2;
4662ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__first1));
46633e519524SHoward Hinnant        }
46643e519524SHoward Hinnant        else
46653e519524SHoward Hinnant        {
4666ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__first1));
46673e519524SHoward Hinnant            __d.__incr((value_type*)0);
46683e519524SHoward Hinnant            ++__first2;
4669ce48a113SHoward Hinnant            ::new(__first2) value_type(_VSTD::move(*__last1));
46703e519524SHoward Hinnant        }
46713e519524SHoward Hinnant        __h2.release();
46723e519524SHoward Hinnant        return;
46733e519524SHoward Hinnant    }
46743e519524SHoward Hinnant    if (__len <= 8)
46753e519524SHoward Hinnant    {
46763e519524SHoward Hinnant        __insertion_sort_move<_Compare>(__first1, __last1, __first2, __comp);
46773e519524SHoward Hinnant        return;
46783e519524SHoward Hinnant    }
46793e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
46803e519524SHoward Hinnant    _RandomAccessIterator __m = __first1 + __l2;
46813e519524SHoward Hinnant    __stable_sort<_Compare>(__first1, __m, __comp, __l2, __first2, __l2);
46823e519524SHoward Hinnant    __stable_sort<_Compare>(__m, __last1, __comp, __len - __l2, __first2 + __l2, __len - __l2);
46833e519524SHoward Hinnant    __merge_move_construct<_Compare>(__first1, __m, __m, __last1, __first2, __comp);
46843e519524SHoward Hinnant}
46853e519524SHoward Hinnant
46863e519524SHoward Hinnanttemplate <class _Tp>
46873e519524SHoward Hinnantstruct __stable_sort_switch
46883e519524SHoward Hinnant{
4689ca740483SHoward Hinnant    static const unsigned value = 128*is_trivially_copy_assignable<_Tp>::value;
46903e519524SHoward Hinnant};
46913e519524SHoward Hinnant
46923e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
46933e519524SHoward Hinnantvoid
46943e519524SHoward Hinnant__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
46953e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::difference_type __len,
46963e519524SHoward Hinnant              typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size)
46973e519524SHoward Hinnant{
46983e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
46993e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47003e519524SHoward Hinnant    switch (__len)
47013e519524SHoward Hinnant    {
47023e519524SHoward Hinnant    case 0:
47033e519524SHoward Hinnant    case 1:
47043e519524SHoward Hinnant        return;
47053e519524SHoward Hinnant    case 2:
47063e519524SHoward Hinnant        if (__comp(*--__last, *__first))
47073e519524SHoward Hinnant            swap(*__first, *__last);
47083e519524SHoward Hinnant        return;
47093e519524SHoward Hinnant    }
47103e519524SHoward Hinnant    if (__len <= static_cast<difference_type>(__stable_sort_switch<value_type>::value))
47113e519524SHoward Hinnant    {
47123e519524SHoward Hinnant        __insertion_sort<_Compare>(__first, __last, __comp);
47133e519524SHoward Hinnant        return;
47143e519524SHoward Hinnant    }
47153e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
47163e519524SHoward Hinnant    _RandomAccessIterator __m = __first + __l2;
47173e519524SHoward Hinnant    if (__len <= __buff_size)
47183e519524SHoward Hinnant    {
47193e519524SHoward Hinnant        __destruct_n __d(0);
47203e519524SHoward Hinnant        unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
47213e519524SHoward Hinnant        __stable_sort_move<_Compare>(__first, __m, __comp, __l2, __buff);
47223e519524SHoward Hinnant        __d.__set(__l2, (value_type*)0);
47233e519524SHoward Hinnant        __stable_sort_move<_Compare>(__m, __last, __comp, __len - __l2, __buff + __l2);
47243e519524SHoward Hinnant        __d.__set(__len, (value_type*)0);
47253e519524SHoward Hinnant        __merge_move_assign<_Compare>(__buff, __buff + __l2, __buff + __l2, __buff + __len, __first, __comp);
47263e519524SHoward Hinnant//         __merge<_Compare>(move_iterator<value_type*>(__buff),
47273e519524SHoward Hinnant//                           move_iterator<value_type*>(__buff + __l2),
47283e519524SHoward Hinnant//                           move_iterator<_RandomAccessIterator>(__buff + __l2),
47293e519524SHoward Hinnant//                           move_iterator<_RandomAccessIterator>(__buff + __len),
47303e519524SHoward Hinnant//                           __first, __comp);
47313e519524SHoward Hinnant        return;
47323e519524SHoward Hinnant    }
47333e519524SHoward Hinnant    __stable_sort<_Compare>(__first, __m, __comp, __l2, __buff, __buff_size);
47343e519524SHoward Hinnant    __stable_sort<_Compare>(__m, __last, __comp, __len - __l2, __buff, __buff_size);
47353e519524SHoward Hinnant    __inplace_merge<_Compare>(__first, __m, __last, __comp, __l2, __len - __l2, __buff, __buff_size);
47363e519524SHoward Hinnant}
47373e519524SHoward Hinnant
47383e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
47393e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
47403e519524SHoward Hinnantvoid
47413e519524SHoward Hinnantstable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
47423e519524SHoward Hinnant{
47433e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
47443e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47453e519524SHoward Hinnant    difference_type __len = __last - __first;
47463e519524SHoward Hinnant    pair<value_type*, ptrdiff_t> __buf(0, 0);
47473e519524SHoward Hinnant    unique_ptr<value_type, __return_temporary_buffer> __h;
47483e519524SHoward Hinnant    if (__len > static_cast<difference_type>(__stable_sort_switch<value_type>::value))
47493e519524SHoward Hinnant    {
4750ce48a113SHoward Hinnant        __buf = _VSTD::get_temporary_buffer<value_type>(__len);
47513e519524SHoward Hinnant        __h.reset(__buf.first);
47523e519524SHoward Hinnant    }
4753aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
47543e519524SHoward Hinnant    __stable_sort<_Comp_ref>(__first, __last, __comp, __len, __buf.first, __buf.second);
47553e519524SHoward Hinnant}
47563e519524SHoward Hinnant
47573e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
47583e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
47593e519524SHoward Hinnantvoid
47603e519524SHoward Hinnantstable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
47613e519524SHoward Hinnant{
4762ce48a113SHoward Hinnant    _VSTD::stable_sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
47633e519524SHoward Hinnant}
47643e519524SHoward Hinnant
47653e519524SHoward Hinnant// is_heap_until
47663e519524SHoward Hinnant
47673e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
47681362d7efSNico Weber_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
47693e519524SHoward Hinnantis_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
47703e519524SHoward Hinnant{
4771ce48a113SHoward Hinnant    typedef typename _VSTD::iterator_traits<_RandomAccessIterator>::difference_type difference_type;
47723e519524SHoward Hinnant    difference_type __len = __last - __first;
47733e519524SHoward Hinnant    difference_type __p = 0;
47743e519524SHoward Hinnant    difference_type __c = 1;
47753e519524SHoward Hinnant    _RandomAccessIterator __pp = __first;
47763e519524SHoward Hinnant    while (__c < __len)
47773e519524SHoward Hinnant    {
47783e519524SHoward Hinnant        _RandomAccessIterator __cp = __first + __c;
47793e519524SHoward Hinnant        if (__comp(*__pp, *__cp))
47803e519524SHoward Hinnant            return __cp;
47813e519524SHoward Hinnant        ++__c;
47823e519524SHoward Hinnant        ++__cp;
47833e519524SHoward Hinnant        if (__c == __len)
47843e519524SHoward Hinnant            return __last;
47853e519524SHoward Hinnant        if (__comp(*__pp, *__cp))
47863e519524SHoward Hinnant            return __cp;
47873e519524SHoward Hinnant        ++__p;
47883e519524SHoward Hinnant        ++__pp;
47893e519524SHoward Hinnant        __c = 2 * __p + 1;
47903e519524SHoward Hinnant    }
47913e519524SHoward Hinnant    return __last;
47923e519524SHoward Hinnant}
47933e519524SHoward Hinnant
47943e519524SHoward Hinnanttemplate<class _RandomAccessIterator>
47951362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
47961362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
47973e519524SHoward Hinnant_RandomAccessIterator
47983e519524SHoward Hinnantis_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
47993e519524SHoward Hinnant{
4800ce48a113SHoward Hinnant    return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48013e519524SHoward Hinnant}
48023e519524SHoward Hinnant
48033e519524SHoward Hinnant// is_heap
48043e519524SHoward Hinnant
48053e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
48061362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
48071362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48083e519524SHoward Hinnantbool
48093e519524SHoward Hinnantis_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
48103e519524SHoward Hinnant{
4811ce48a113SHoward Hinnant    return _VSTD::is_heap_until(__first, __last, __comp) == __last;
48123e519524SHoward Hinnant}
48133e519524SHoward Hinnant
48143e519524SHoward Hinnanttemplate<class _RandomAccessIterator>
48151362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
48161362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
48173e519524SHoward Hinnantbool
48183e519524SHoward Hinnantis_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
48193e519524SHoward Hinnant{
4820ce48a113SHoward Hinnant    return _VSTD::is_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48213e519524SHoward Hinnant}
48223e519524SHoward Hinnant
48233e519524SHoward Hinnant// push_heap
48243e519524SHoward Hinnant
48253e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
48263e519524SHoward Hinnantvoid
48278b512602SDavid Majnemer__sift_up(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
48283e519524SHoward Hinnant          typename iterator_traits<_RandomAccessIterator>::difference_type __len)
48293e519524SHoward Hinnant{
48303e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
48313e519524SHoward Hinnant    if (__len > 1)
48323e519524SHoward Hinnant    {
48333e519524SHoward Hinnant        __len = (__len - 2) / 2;
48343e519524SHoward Hinnant        _RandomAccessIterator __ptr = __first + __len;
48353e519524SHoward Hinnant        if (__comp(*__ptr, *--__last))
48363e519524SHoward Hinnant        {
4837ce48a113SHoward Hinnant            value_type __t(_VSTD::move(*__last));
48383e519524SHoward Hinnant            do
48393e519524SHoward Hinnant            {
4840ce48a113SHoward Hinnant                *__last = _VSTD::move(*__ptr);
48413e519524SHoward Hinnant                __last = __ptr;
48423e519524SHoward Hinnant                if (__len == 0)
48433e519524SHoward Hinnant                    break;
48443e519524SHoward Hinnant                __len = (__len - 1) / 2;
48453e519524SHoward Hinnant                __ptr = __first + __len;
48463e519524SHoward Hinnant            } while (__comp(*__ptr, __t));
4847ce48a113SHoward Hinnant            *__last = _VSTD::move(__t);
48483e519524SHoward Hinnant        }
48493e519524SHoward Hinnant    }
48503e519524SHoward Hinnant}
48513e519524SHoward Hinnant
48523e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
48533e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
48543e519524SHoward Hinnantvoid
48553e519524SHoward Hinnantpush_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
48563e519524SHoward Hinnant{
4857aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
48588b512602SDavid Majnemer    __sift_up<_Comp_ref>(__first, __last, __comp, __last - __first);
48593e519524SHoward Hinnant}
48603e519524SHoward Hinnant
48613e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
48623e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
48633e519524SHoward Hinnantvoid
48643e519524SHoward Hinnantpush_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
48653e519524SHoward Hinnant{
4866ce48a113SHoward Hinnant    _VSTD::push_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
48673e519524SHoward Hinnant}
48683e519524SHoward Hinnant
48693e519524SHoward Hinnant// pop_heap
48703e519524SHoward Hinnant
48713e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
48728b512602SDavid Majnemervoid
4873fd838227SEric Fiselier__sift_down(_RandomAccessIterator __first, _RandomAccessIterator /*__last*/,
4874fd838227SEric Fiselier            _Compare __comp,
48758b512602SDavid Majnemer            typename iterator_traits<_RandomAccessIterator>::difference_type __len,
48768b512602SDavid Majnemer            _RandomAccessIterator __start)
48778b512602SDavid Majnemer{
48788b512602SDavid Majnemer    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
48798b512602SDavid Majnemer    typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
48808b512602SDavid Majnemer    // left-child of __start is at 2 * __start + 1
48818b512602SDavid Majnemer    // right-child of __start is at 2 * __start + 2
48828b512602SDavid Majnemer    difference_type __child = __start - __first;
48838b512602SDavid Majnemer
48848b512602SDavid Majnemer    if (__len < 2 || (__len - 2) / 2 < __child)
48858b512602SDavid Majnemer        return;
48868b512602SDavid Majnemer
48878b512602SDavid Majnemer    __child = 2 * __child + 1;
48888b512602SDavid Majnemer    _RandomAccessIterator __child_i = __first + __child;
48898b512602SDavid Majnemer
48908b512602SDavid Majnemer    if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
48918b512602SDavid Majnemer        // right-child exists and is greater than left-child
48928b512602SDavid Majnemer        ++__child_i;
48938b512602SDavid Majnemer        ++__child;
48948b512602SDavid Majnemer    }
48958b512602SDavid Majnemer
48968b512602SDavid Majnemer    // check if we are in heap-order
48978b512602SDavid Majnemer    if (__comp(*__child_i, *__start))
48988b512602SDavid Majnemer        // we are, __start is larger than it's largest child
48998b512602SDavid Majnemer        return;
49008b512602SDavid Majnemer
49018b512602SDavid Majnemer    value_type __top(_VSTD::move(*__start));
49028b512602SDavid Majnemer    do
49038b512602SDavid Majnemer    {
49048b512602SDavid Majnemer        // we are not in heap-order, swap the parent with it's largest child
49058b512602SDavid Majnemer        *__start = _VSTD::move(*__child_i);
49068b512602SDavid Majnemer        __start = __child_i;
49078b512602SDavid Majnemer
49088b512602SDavid Majnemer        if ((__len - 2) / 2 < __child)
49098b512602SDavid Majnemer            break;
49108b512602SDavid Majnemer
49118b512602SDavid Majnemer        // recompute the child based off of the updated parent
49128b512602SDavid Majnemer        __child = 2 * __child + 1;
49138b512602SDavid Majnemer        __child_i = __first + __child;
49148b512602SDavid Majnemer
49158b512602SDavid Majnemer        if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
49168b512602SDavid Majnemer            // right-child exists and is greater than left-child
49178b512602SDavid Majnemer            ++__child_i;
49188b512602SDavid Majnemer            ++__child;
49198b512602SDavid Majnemer        }
49208b512602SDavid Majnemer
49218b512602SDavid Majnemer        // check if we are in heap-order
49228b512602SDavid Majnemer    } while (!__comp(*__child_i, __top));
49238b512602SDavid Majnemer    *__start = _VSTD::move(__top);
49248b512602SDavid Majnemer}
49258b512602SDavid Majnemer
49268b512602SDavid Majnemertemplate <class _Compare, class _RandomAccessIterator>
49273e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49283e519524SHoward Hinnantvoid
49293e519524SHoward Hinnant__pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
49303e519524SHoward Hinnant           typename iterator_traits<_RandomAccessIterator>::difference_type __len)
49313e519524SHoward Hinnant{
49323e519524SHoward Hinnant    if (__len > 1)
49333e519524SHoward Hinnant    {
49343e519524SHoward Hinnant        swap(*__first, *--__last);
49358b512602SDavid Majnemer        __sift_down<_Compare>(__first, __last, __comp, __len - 1, __first);
49363e519524SHoward Hinnant    }
49373e519524SHoward Hinnant}
49383e519524SHoward Hinnant
49393e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
49403e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49413e519524SHoward Hinnantvoid
49423e519524SHoward Hinnantpop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49433e519524SHoward Hinnant{
4944aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
49453e519524SHoward Hinnant    __pop_heap<_Comp_ref>(__first, __last, __comp, __last - __first);
49463e519524SHoward Hinnant}
49473e519524SHoward Hinnant
49483e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
49493e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49503e519524SHoward Hinnantvoid
49513e519524SHoward Hinnantpop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
49523e519524SHoward Hinnant{
4953ce48a113SHoward Hinnant    _VSTD::pop_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
49543e519524SHoward Hinnant}
49553e519524SHoward Hinnant
49563e519524SHoward Hinnant// make_heap
49573e519524SHoward Hinnant
49583e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
49593e519524SHoward Hinnantvoid
49603e519524SHoward Hinnant__make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49613e519524SHoward Hinnant{
49623e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
49633e519524SHoward Hinnant    difference_type __n = __last - __first;
49643e519524SHoward Hinnant    if (__n > 1)
49653e519524SHoward Hinnant    {
49668b512602SDavid Majnemer        // start from the first parent, there is no need to consider children
49678b512602SDavid Majnemer        for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start)
49688b512602SDavid Majnemer        {
49698b512602SDavid Majnemer            __sift_down<_Compare>(__first, __last, __comp, __n, __first + __start);
49708b512602SDavid Majnemer        }
49713e519524SHoward Hinnant    }
49723e519524SHoward Hinnant}
49733e519524SHoward Hinnant
49743e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
49753e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49763e519524SHoward Hinnantvoid
49773e519524SHoward Hinnantmake_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49783e519524SHoward Hinnant{
4979aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
49803e519524SHoward Hinnant    __make_heap<_Comp_ref>(__first, __last, __comp);
49813e519524SHoward Hinnant}
49823e519524SHoward Hinnant
49833e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
49843e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
49853e519524SHoward Hinnantvoid
49863e519524SHoward Hinnantmake_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
49873e519524SHoward Hinnant{
4988ce48a113SHoward Hinnant    _VSTD::make_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
49893e519524SHoward Hinnant}
49903e519524SHoward Hinnant
49913e519524SHoward Hinnant// sort_heap
49923e519524SHoward Hinnant
49933e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
49943e519524SHoward Hinnantvoid
49953e519524SHoward Hinnant__sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
49963e519524SHoward Hinnant{
49973e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
4998*7fa68653SMarshall Clow    for (difference_type __n = __last - __first; __n > 1; --__last, (void) --__n)
49993e519524SHoward Hinnant        __pop_heap<_Compare>(__first, __last, __comp, __n);
50003e519524SHoward Hinnant}
50013e519524SHoward Hinnant
50023e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
50033e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50043e519524SHoward Hinnantvoid
50053e519524SHoward Hinnantsort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
50063e519524SHoward Hinnant{
5007aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
50083e519524SHoward Hinnant    __sort_heap<_Comp_ref>(__first, __last, __comp);
50093e519524SHoward Hinnant}
50103e519524SHoward Hinnant
50113e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
50123e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50133e519524SHoward Hinnantvoid
50143e519524SHoward Hinnantsort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
50153e519524SHoward Hinnant{
5016ce48a113SHoward Hinnant    _VSTD::sort_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50173e519524SHoward Hinnant}
50183e519524SHoward Hinnant
50193e519524SHoward Hinnant// partial_sort
50203e519524SHoward Hinnant
50213e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
50223e519524SHoward Hinnantvoid
50233e519524SHoward Hinnant__partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
50243e519524SHoward Hinnant             _Compare __comp)
50253e519524SHoward Hinnant{
50263e519524SHoward Hinnant    __make_heap<_Compare>(__first, __middle, __comp);
50273e519524SHoward Hinnant    typename iterator_traits<_RandomAccessIterator>::difference_type __len = __middle - __first;
50283e519524SHoward Hinnant    for (_RandomAccessIterator __i = __middle; __i != __last; ++__i)
50293e519524SHoward Hinnant    {
50303e519524SHoward Hinnant        if (__comp(*__i, *__first))
50313e519524SHoward Hinnant        {
50323e519524SHoward Hinnant            swap(*__i, *__first);
50338b512602SDavid Majnemer            __sift_down<_Compare>(__first, __middle, __comp, __len, __first);
50343e519524SHoward Hinnant        }
50353e519524SHoward Hinnant    }
50363e519524SHoward Hinnant    __sort_heap<_Compare>(__first, __middle, __comp);
50373e519524SHoward Hinnant}
50383e519524SHoward Hinnant
50393e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
50403e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50413e519524SHoward Hinnantvoid
50423e519524SHoward Hinnantpartial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
50433e519524SHoward Hinnant             _Compare __comp)
50443e519524SHoward Hinnant{
5045aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
50463e519524SHoward Hinnant    __partial_sort<_Comp_ref>(__first, __middle, __last, __comp);
50473e519524SHoward Hinnant}
50483e519524SHoward Hinnant
50493e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
50503e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50513e519524SHoward Hinnantvoid
50523e519524SHoward Hinnantpartial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
50533e519524SHoward Hinnant{
5054ce48a113SHoward Hinnant    _VSTD::partial_sort(__first, __middle, __last,
50553e519524SHoward Hinnant                       __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
50563e519524SHoward Hinnant}
50573e519524SHoward Hinnant
50583e519524SHoward Hinnant// partial_sort_copy
50593e519524SHoward Hinnant
50603e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator, class _RandomAccessIterator>
50613e519524SHoward Hinnant_RandomAccessIterator
50623e519524SHoward Hinnant__partial_sort_copy(_InputIterator __first, _InputIterator __last,
50633e519524SHoward Hinnant                    _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
50643e519524SHoward Hinnant{
50653e519524SHoward Hinnant    _RandomAccessIterator __r = __result_first;
50663e519524SHoward Hinnant    if (__r != __result_last)
50673e519524SHoward Hinnant    {
5068*7fa68653SMarshall Clow        for (; __first != __last && __r != __result_last; ++__first, (void) ++__r)
50693e519524SHoward Hinnant            *__r = *__first;
50703e519524SHoward Hinnant        __make_heap<_Compare>(__result_first, __r, __comp);
50718b512602SDavid Majnemer        typename iterator_traits<_RandomAccessIterator>::difference_type __len = __r - __result_first;
50723e519524SHoward Hinnant        for (; __first != __last; ++__first)
50733e519524SHoward Hinnant            if (__comp(*__first, *__result_first))
50743e519524SHoward Hinnant            {
50753e519524SHoward Hinnant                *__result_first = *__first;
50768b512602SDavid Majnemer                __sift_down<_Compare>(__result_first, __r, __comp, __len, __result_first);
50773e519524SHoward Hinnant            }
50783e519524SHoward Hinnant        __sort_heap<_Compare>(__result_first, __r, __comp);
50793e519524SHoward Hinnant    }
50803e519524SHoward Hinnant    return __r;
50813e519524SHoward Hinnant}
50823e519524SHoward Hinnant
50833e519524SHoward Hinnanttemplate <class _InputIterator, class _RandomAccessIterator, class _Compare>
50843e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50853e519524SHoward Hinnant_RandomAccessIterator
50863e519524SHoward Hinnantpartial_sort_copy(_InputIterator __first, _InputIterator __last,
50873e519524SHoward Hinnant                  _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
50883e519524SHoward Hinnant{
5089aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
50903e519524SHoward Hinnant    return __partial_sort_copy<_Comp_ref>(__first, __last, __result_first, __result_last, __comp);
50913e519524SHoward Hinnant}
50923e519524SHoward Hinnant
50933e519524SHoward Hinnanttemplate <class _InputIterator, class _RandomAccessIterator>
50943e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
50953e519524SHoward Hinnant_RandomAccessIterator
50963e519524SHoward Hinnantpartial_sort_copy(_InputIterator __first, _InputIterator __last,
50973e519524SHoward Hinnant                  _RandomAccessIterator __result_first, _RandomAccessIterator __result_last)
50983e519524SHoward Hinnant{
5099ce48a113SHoward Hinnant    return _VSTD::partial_sort_copy(__first, __last, __result_first, __result_last,
51003e519524SHoward Hinnant                                   __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
51013e519524SHoward Hinnant}
51023e519524SHoward Hinnant
51033e519524SHoward Hinnant// nth_element
51043e519524SHoward Hinnant
51053e519524SHoward Hinnanttemplate <class _Compare, class _RandomAccessIterator>
51063e519524SHoward Hinnantvoid
51073e519524SHoward Hinnant__nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
51083e519524SHoward Hinnant{
51093e519524SHoward Hinnant    // _Compare is known to be a reference type
51103e519524SHoward Hinnant    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
51113e519524SHoward Hinnant    const difference_type __limit = 7;
51123e519524SHoward Hinnant    while (true)
51133e519524SHoward Hinnant    {
51143e519524SHoward Hinnant    __restart:
5115b34b4819SHoward Hinnant        if (__nth == __last)
5116b34b4819SHoward Hinnant            return;
51173e519524SHoward Hinnant        difference_type __len = __last - __first;
51183e519524SHoward Hinnant        switch (__len)
51193e519524SHoward Hinnant        {
51203e519524SHoward Hinnant        case 0:
51213e519524SHoward Hinnant        case 1:
51223e519524SHoward Hinnant            return;
51233e519524SHoward Hinnant        case 2:
51243e519524SHoward Hinnant            if (__comp(*--__last, *__first))
51253e519524SHoward Hinnant                swap(*__first, *__last);
51263e519524SHoward Hinnant            return;
51273e519524SHoward Hinnant        case 3:
51283e519524SHoward Hinnant            {
51293e519524SHoward Hinnant            _RandomAccessIterator __m = __first;
5130ce48a113SHoward Hinnant            _VSTD::__sort3<_Compare>(__first, ++__m, --__last, __comp);
51313e519524SHoward Hinnant            return;
51323e519524SHoward Hinnant            }
51333e519524SHoward Hinnant        }
51343e519524SHoward Hinnant        if (__len <= __limit)
51353e519524SHoward Hinnant        {
51363e519524SHoward Hinnant            __selection_sort<_Compare>(__first, __last, __comp);
51373e519524SHoward Hinnant            return;
51383e519524SHoward Hinnant        }
51393e519524SHoward Hinnant        // __len > __limit >= 3
51403e519524SHoward Hinnant        _RandomAccessIterator __m = __first + __len/2;
51413e519524SHoward Hinnant        _RandomAccessIterator __lm1 = __last;
5142ce48a113SHoward Hinnant        unsigned __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, --__lm1, __comp);
51433e519524SHoward Hinnant        // *__m is median
51443e519524SHoward Hinnant        // partition [__first, __m) < *__m and *__m <= [__m, __last)
51453e519524SHoward Hinnant        // (this inhibits tossing elements equivalent to __m around unnecessarily)
51463e519524SHoward Hinnant        _RandomAccessIterator __i = __first;
51473e519524SHoward Hinnant        _RandomAccessIterator __j = __lm1;
51483e519524SHoward Hinnant        // j points beyond range to be tested, *__lm1 is known to be <= *__m
51493e519524SHoward Hinnant        // The search going up is known to be guarded but the search coming down isn't.
51503e519524SHoward Hinnant        // Prime the downward search with a guard.
51513e519524SHoward Hinnant        if (!__comp(*__i, *__m))  // if *__first == *__m
51523e519524SHoward Hinnant        {
51533e519524SHoward Hinnant            // *__first == *__m, *__first doesn't go in first part
51543e519524SHoward Hinnant            // manually guard downward moving __j against __i
51553e519524SHoward Hinnant            while (true)
51563e519524SHoward Hinnant            {
51573e519524SHoward Hinnant                if (__i == --__j)
51583e519524SHoward Hinnant                {
51593e519524SHoward Hinnant                    // *__first == *__m, *__m <= all other elements
51603e519524SHoward Hinnant                    // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
51613e519524SHoward Hinnant                    ++__i;  // __first + 1
51623e519524SHoward Hinnant                    __j = __last;
51633e519524SHoward Hinnant                    if (!__comp(*__first, *--__j))  // we need a guard if *__first == *(__last-1)
51643e519524SHoward Hinnant                    {
51653e519524SHoward Hinnant                        while (true)
51663e519524SHoward Hinnant                        {
51673e519524SHoward Hinnant                            if (__i == __j)
51683e519524SHoward Hinnant                                return;  // [__first, __last) all equivalent elements
51693e519524SHoward Hinnant                            if (__comp(*__first, *__i))
51703e519524SHoward Hinnant                            {
51713e519524SHoward Hinnant                                swap(*__i, *__j);
51723e519524SHoward Hinnant                                ++__n_swaps;
51733e519524SHoward Hinnant                                ++__i;
51743e519524SHoward Hinnant                                break;
51753e519524SHoward Hinnant                            }
51763e519524SHoward Hinnant                            ++__i;
51773e519524SHoward Hinnant                        }
51783e519524SHoward Hinnant                    }
51793e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
51803e519524SHoward Hinnant                    if (__i == __j)
51813e519524SHoward Hinnant                        return;
51823e519524SHoward Hinnant                    while (true)
51833e519524SHoward Hinnant                    {
51843e519524SHoward Hinnant                        while (!__comp(*__first, *__i))
51853e519524SHoward Hinnant                            ++__i;
51863e519524SHoward Hinnant                        while (__comp(*__first, *--__j))
51873e519524SHoward Hinnant                            ;
51883e519524SHoward Hinnant                        if (__i >= __j)
51893e519524SHoward Hinnant                            break;
51903e519524SHoward Hinnant                        swap(*__i, *__j);
51913e519524SHoward Hinnant                        ++__n_swaps;
51923e519524SHoward Hinnant                        ++__i;
51933e519524SHoward Hinnant                    }
51943e519524SHoward Hinnant                    // [__first, __i) == *__first and *__first < [__i, __last)
51953e519524SHoward Hinnant                    // The first part is sorted,
51963e519524SHoward Hinnant                    if (__nth < __i)
51973e519524SHoward Hinnant                        return;
51983e519524SHoward Hinnant                    // __nth_element the secod part
51993e519524SHoward Hinnant                    // __nth_element<_Compare>(__i, __nth, __last, __comp);
52003e519524SHoward Hinnant                    __first = __i;
52013e519524SHoward Hinnant                    goto __restart;
52023e519524SHoward Hinnant                }
52033e519524SHoward Hinnant                if (__comp(*__j, *__m))
52043e519524SHoward Hinnant                {
52053e519524SHoward Hinnant                    swap(*__i, *__j);
52063e519524SHoward Hinnant                    ++__n_swaps;
52073e519524SHoward Hinnant                    break;  // found guard for downward moving __j, now use unguarded partition
52083e519524SHoward Hinnant                }
52093e519524SHoward Hinnant            }
52103e519524SHoward Hinnant        }
52113e519524SHoward Hinnant        ++__i;
52123e519524SHoward Hinnant        // j points beyond range to be tested, *__lm1 is known to be <= *__m
52133e519524SHoward Hinnant        // if not yet partitioned...
52143e519524SHoward Hinnant        if (__i < __j)
52153e519524SHoward Hinnant        {
52163e519524SHoward Hinnant            // known that *(__i - 1) < *__m
52173e519524SHoward Hinnant            while (true)
52183e519524SHoward Hinnant            {
52193e519524SHoward Hinnant                // __m still guards upward moving __i
52203e519524SHoward Hinnant                while (__comp(*__i, *__m))
52213e519524SHoward Hinnant                    ++__i;
52223e519524SHoward Hinnant                // It is now known that a guard exists for downward moving __j
52233e519524SHoward Hinnant                while (!__comp(*--__j, *__m))
52243e519524SHoward Hinnant                    ;
52253e519524SHoward Hinnant                if (__i >= __j)
52263e519524SHoward Hinnant                    break;
52273e519524SHoward Hinnant                swap(*__i, *__j);
52283e519524SHoward Hinnant                ++__n_swaps;
52293e519524SHoward Hinnant                // It is known that __m != __j
52303e519524SHoward Hinnant                // If __m just moved, follow it
52313e519524SHoward Hinnant                if (__m == __i)
52323e519524SHoward Hinnant                    __m = __j;
52333e519524SHoward Hinnant                ++__i;
52343e519524SHoward Hinnant            }
52353e519524SHoward Hinnant        }
52363e519524SHoward Hinnant        // [__first, __i) < *__m and *__m <= [__i, __last)
52373e519524SHoward Hinnant        if (__i != __m && __comp(*__m, *__i))
52383e519524SHoward Hinnant        {
52393e519524SHoward Hinnant            swap(*__i, *__m);
52403e519524SHoward Hinnant            ++__n_swaps;
52413e519524SHoward Hinnant        }
52423e519524SHoward Hinnant        // [__first, __i) < *__i and *__i <= [__i+1, __last)
52433e519524SHoward Hinnant        if (__nth == __i)
52443e519524SHoward Hinnant            return;
52453e519524SHoward Hinnant        if (__n_swaps == 0)
52463e519524SHoward Hinnant        {
52473e519524SHoward Hinnant            // We were given a perfectly partitioned sequence.  Coincidence?
52483e519524SHoward Hinnant            if (__nth < __i)
52493e519524SHoward Hinnant            {
52503e519524SHoward Hinnant                // Check for [__first, __i) already sorted
52513e519524SHoward Hinnant                __j = __m = __first;
52523e519524SHoward Hinnant                while (++__j != __i)
52533e519524SHoward Hinnant                {
52543e519524SHoward Hinnant                    if (__comp(*__j, *__m))
52553e519524SHoward Hinnant                        // not yet sorted, so sort
52563e519524SHoward Hinnant                        goto not_sorted;
52573e519524SHoward Hinnant                    __m = __j;
52583e519524SHoward Hinnant                }
52593e519524SHoward Hinnant                // [__first, __i) sorted
52603e519524SHoward Hinnant                return;
52613e519524SHoward Hinnant            }
52623e519524SHoward Hinnant            else
52633e519524SHoward Hinnant            {
52643e519524SHoward Hinnant                // Check for [__i, __last) already sorted
52653e519524SHoward Hinnant                __j = __m = __i;
52663e519524SHoward Hinnant                while (++__j != __last)
52673e519524SHoward Hinnant                {
52683e519524SHoward Hinnant                    if (__comp(*__j, *__m))
52693e519524SHoward Hinnant                        // not yet sorted, so sort
52703e519524SHoward Hinnant                        goto not_sorted;
52713e519524SHoward Hinnant                    __m = __j;
52723e519524SHoward Hinnant                }
52733e519524SHoward Hinnant                // [__i, __last) sorted
52743e519524SHoward Hinnant                return;
52753e519524SHoward Hinnant            }
52763e519524SHoward Hinnant        }
52773e519524SHoward Hinnantnot_sorted:
52783e519524SHoward Hinnant        // __nth_element on range containing __nth
52793e519524SHoward Hinnant        if (__nth < __i)
52803e519524SHoward Hinnant        {
52813e519524SHoward Hinnant            // __nth_element<_Compare>(__first, __nth, __i, __comp);
52823e519524SHoward Hinnant            __last = __i;
52833e519524SHoward Hinnant        }
52843e519524SHoward Hinnant        else
52853e519524SHoward Hinnant        {
52863e519524SHoward Hinnant            // __nth_element<_Compare>(__i+1, __nth, __last, __comp);
52873e519524SHoward Hinnant            __first = ++__i;
52883e519524SHoward Hinnant        }
52893e519524SHoward Hinnant    }
52903e519524SHoward Hinnant}
52913e519524SHoward Hinnant
52923e519524SHoward Hinnanttemplate <class _RandomAccessIterator, class _Compare>
52933e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
52943e519524SHoward Hinnantvoid
52953e519524SHoward Hinnantnth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
52963e519524SHoward Hinnant{
5297aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
52983e519524SHoward Hinnant    __nth_element<_Comp_ref>(__first, __nth, __last, __comp);
52993e519524SHoward Hinnant}
53003e519524SHoward Hinnant
53013e519524SHoward Hinnanttemplate <class _RandomAccessIterator>
53023e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
53033e519524SHoward Hinnantvoid
53043e519524SHoward Hinnantnth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last)
53053e519524SHoward Hinnant{
5306ce48a113SHoward Hinnant    _VSTD::nth_element(__first, __nth, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
53073e519524SHoward Hinnant}
53083e519524SHoward Hinnant
53093e519524SHoward Hinnant// includes
53103e519524SHoward Hinnant
53113e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2>
53128da1a487SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
53133e519524SHoward Hinnant__includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
53143e519524SHoward Hinnant           _Compare __comp)
53153e519524SHoward Hinnant{
53163e519524SHoward Hinnant    for (; __first2 != __last2; ++__first1)
53173e519524SHoward Hinnant    {
53183e519524SHoward Hinnant        if (__first1 == __last1 || __comp(*__first2, *__first1))
53193e519524SHoward Hinnant            return false;
53203e519524SHoward Hinnant        if (!__comp(*__first1, *__first2))
53213e519524SHoward Hinnant            ++__first2;
53223e519524SHoward Hinnant    }
53233e519524SHoward Hinnant    return true;
53243e519524SHoward Hinnant}
53253e519524SHoward Hinnant
53263e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _Compare>
53271362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
53281362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
53293e519524SHoward Hinnantbool
53303e519524SHoward Hinnantincludes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
53313e519524SHoward Hinnant         _Compare __comp)
53323e519524SHoward Hinnant{
5333aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
53343e519524SHoward Hinnant    return __includes<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
53353e519524SHoward Hinnant}
53363e519524SHoward Hinnant
53373e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
53381362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
53391362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
53403e519524SHoward Hinnantbool
53413e519524SHoward Hinnantincludes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)
53423e519524SHoward Hinnant{
5343ce48a113SHoward Hinnant    return _VSTD::includes(__first1, __last1, __first2, __last2,
53443e519524SHoward Hinnant                          __less<typename iterator_traits<_InputIterator1>::value_type,
53453e519524SHoward Hinnant                                 typename iterator_traits<_InputIterator2>::value_type>());
53463e519524SHoward Hinnant}
53473e519524SHoward Hinnant
53483e519524SHoward Hinnant// set_union
53493e519524SHoward Hinnant
53503e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
53513e519524SHoward Hinnant_OutputIterator
53523e519524SHoward Hinnant__set_union(_InputIterator1 __first1, _InputIterator1 __last1,
53533e519524SHoward Hinnant            _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
53543e519524SHoward Hinnant{
53553e519524SHoward Hinnant    for (; __first1 != __last1; ++__result)
53563e519524SHoward Hinnant    {
53573e519524SHoward Hinnant        if (__first2 == __last2)
5358ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
53593e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
53603e519524SHoward Hinnant        {
53613e519524SHoward Hinnant            *__result = *__first2;
53623e519524SHoward Hinnant            ++__first2;
53633e519524SHoward Hinnant        }
53643e519524SHoward Hinnant        else
53653e519524SHoward Hinnant        {
53663e519524SHoward Hinnant            if (!__comp(*__first1, *__first2))
53673e519524SHoward Hinnant                ++__first2;
536805da5b02SMarshall Clow            *__result = *__first1;
53693e519524SHoward Hinnant            ++__first1;
53703e519524SHoward Hinnant        }
53713e519524SHoward Hinnant    }
5372ce48a113SHoward Hinnant    return _VSTD::copy(__first2, __last2, __result);
53733e519524SHoward Hinnant}
53743e519524SHoward Hinnant
53753e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
53763e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
53773e519524SHoward Hinnant_OutputIterator
53783e519524SHoward Hinnantset_union(_InputIterator1 __first1, _InputIterator1 __last1,
53793e519524SHoward Hinnant          _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
53803e519524SHoward Hinnant{
5381aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
53823e519524SHoward Hinnant    return __set_union<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
53833e519524SHoward Hinnant}
53843e519524SHoward Hinnant
53853e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
53863e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
53873e519524SHoward Hinnant_OutputIterator
53883e519524SHoward Hinnantset_union(_InputIterator1 __first1, _InputIterator1 __last1,
53893e519524SHoward Hinnant          _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
53903e519524SHoward Hinnant{
5391ce48a113SHoward Hinnant    return _VSTD::set_union(__first1, __last1, __first2, __last2, __result,
53923e519524SHoward Hinnant                          __less<typename iterator_traits<_InputIterator1>::value_type,
53933e519524SHoward Hinnant                                 typename iterator_traits<_InputIterator2>::value_type>());
53943e519524SHoward Hinnant}
53953e519524SHoward Hinnant
53963e519524SHoward Hinnant// set_intersection
53973e519524SHoward Hinnant
53983e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
53998da1a487SMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
54003e519524SHoward Hinnant__set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54013e519524SHoward Hinnant                   _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54023e519524SHoward Hinnant{
54033e519524SHoward Hinnant    while (__first1 != __last1 && __first2 != __last2)
54043e519524SHoward Hinnant    {
54053e519524SHoward Hinnant        if (__comp(*__first1, *__first2))
54063e519524SHoward Hinnant            ++__first1;
54073e519524SHoward Hinnant        else
54083e519524SHoward Hinnant        {
54093e519524SHoward Hinnant            if (!__comp(*__first2, *__first1))
54103e519524SHoward Hinnant            {
54113e519524SHoward Hinnant                *__result = *__first1;
54123e519524SHoward Hinnant                ++__result;
54133e519524SHoward Hinnant                ++__first1;
54143e519524SHoward Hinnant            }
54153e519524SHoward Hinnant            ++__first2;
54163e519524SHoward Hinnant        }
54173e519524SHoward Hinnant    }
54183e519524SHoward Hinnant    return __result;
54193e519524SHoward Hinnant}
54203e519524SHoward Hinnant
54213e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
54228da1a487SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
54233e519524SHoward Hinnant_OutputIterator
54243e519524SHoward Hinnantset_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54253e519524SHoward Hinnant                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54263e519524SHoward Hinnant{
5427aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
54283e519524SHoward Hinnant    return __set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
54293e519524SHoward Hinnant}
54303e519524SHoward Hinnant
54313e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
54328da1a487SMarshall Clowinline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
54333e519524SHoward Hinnant_OutputIterator
54343e519524SHoward Hinnantset_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
54353e519524SHoward Hinnant                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
54363e519524SHoward Hinnant{
5437ce48a113SHoward Hinnant    return _VSTD::set_intersection(__first1, __last1, __first2, __last2, __result,
54383e519524SHoward Hinnant                                  __less<typename iterator_traits<_InputIterator1>::value_type,
54393e519524SHoward Hinnant                                         typename iterator_traits<_InputIterator2>::value_type>());
54403e519524SHoward Hinnant}
54413e519524SHoward Hinnant
54423e519524SHoward Hinnant// set_difference
54433e519524SHoward Hinnant
54443e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
54453e519524SHoward Hinnant_OutputIterator
54463e519524SHoward Hinnant__set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54473e519524SHoward Hinnant                 _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54483e519524SHoward Hinnant{
54493e519524SHoward Hinnant    while (__first1 != __last1)
54503e519524SHoward Hinnant    {
54513e519524SHoward Hinnant        if (__first2 == __last2)
5452ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
54533e519524SHoward Hinnant        if (__comp(*__first1, *__first2))
54543e519524SHoward Hinnant        {
54553e519524SHoward Hinnant            *__result = *__first1;
54563e519524SHoward Hinnant            ++__result;
54573e519524SHoward Hinnant            ++__first1;
54583e519524SHoward Hinnant        }
54593e519524SHoward Hinnant        else
54603e519524SHoward Hinnant        {
54613e519524SHoward Hinnant            if (!__comp(*__first2, *__first1))
54623e519524SHoward Hinnant                ++__first1;
54633e519524SHoward Hinnant            ++__first2;
54643e519524SHoward Hinnant        }
54653e519524SHoward Hinnant    }
54663e519524SHoward Hinnant    return __result;
54673e519524SHoward Hinnant}
54683e519524SHoward Hinnant
54693e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
54703e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
54713e519524SHoward Hinnant_OutputIterator
54723e519524SHoward Hinnantset_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54733e519524SHoward Hinnant               _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54743e519524SHoward Hinnant{
5475aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
54763e519524SHoward Hinnant    return __set_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
54773e519524SHoward Hinnant}
54783e519524SHoward Hinnant
54793e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
54803e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
54813e519524SHoward Hinnant_OutputIterator
54823e519524SHoward Hinnantset_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54833e519524SHoward Hinnant               _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
54843e519524SHoward Hinnant{
5485ce48a113SHoward Hinnant    return _VSTD::set_difference(__first1, __last1, __first2, __last2, __result,
54863e519524SHoward Hinnant                                __less<typename iterator_traits<_InputIterator1>::value_type,
54873e519524SHoward Hinnant                                       typename iterator_traits<_InputIterator2>::value_type>());
54883e519524SHoward Hinnant}
54893e519524SHoward Hinnant
54903e519524SHoward Hinnant// set_symmetric_difference
54913e519524SHoward Hinnant
54923e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
54933e519524SHoward Hinnant_OutputIterator
54943e519524SHoward Hinnant__set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
54953e519524SHoward Hinnant                           _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
54963e519524SHoward Hinnant{
54973e519524SHoward Hinnant    while (__first1 != __last1)
54983e519524SHoward Hinnant    {
54993e519524SHoward Hinnant        if (__first2 == __last2)
5500ce48a113SHoward Hinnant            return _VSTD::copy(__first1, __last1, __result);
55013e519524SHoward Hinnant        if (__comp(*__first1, *__first2))
55023e519524SHoward Hinnant        {
55033e519524SHoward Hinnant            *__result = *__first1;
55043e519524SHoward Hinnant            ++__result;
55053e519524SHoward Hinnant            ++__first1;
55063e519524SHoward Hinnant        }
55073e519524SHoward Hinnant        else
55083e519524SHoward Hinnant        {
55093e519524SHoward Hinnant            if (__comp(*__first2, *__first1))
55103e519524SHoward Hinnant            {
55113e519524SHoward Hinnant                *__result = *__first2;
55123e519524SHoward Hinnant                ++__result;
55133e519524SHoward Hinnant            }
55143e519524SHoward Hinnant            else
55153e519524SHoward Hinnant                ++__first1;
55163e519524SHoward Hinnant            ++__first2;
55173e519524SHoward Hinnant        }
55183e519524SHoward Hinnant    }
5519ce48a113SHoward Hinnant    return _VSTD::copy(__first2, __last2, __result);
55203e519524SHoward Hinnant}
55213e519524SHoward Hinnant
55223e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
55233e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
55243e519524SHoward Hinnant_OutputIterator
55253e519524SHoward Hinnantset_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55263e519524SHoward Hinnant                         _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
55273e519524SHoward Hinnant{
5528aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
55293e519524SHoward Hinnant    return __set_symmetric_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
55303e519524SHoward Hinnant}
55313e519524SHoward Hinnant
55323e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _OutputIterator>
55333e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
55343e519524SHoward Hinnant_OutputIterator
55353e519524SHoward Hinnantset_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
55363e519524SHoward Hinnant                         _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
55373e519524SHoward Hinnant{
5538ce48a113SHoward Hinnant    return _VSTD::set_symmetric_difference(__first1, __last1, __first2, __last2, __result,
55393e519524SHoward Hinnant                                          __less<typename iterator_traits<_InputIterator1>::value_type,
55403e519524SHoward Hinnant                                                 typename iterator_traits<_InputIterator2>::value_type>());
55413e519524SHoward Hinnant}
55423e519524SHoward Hinnant
55433e519524SHoward Hinnant// lexicographical_compare
55443e519524SHoward Hinnant
55453e519524SHoward Hinnanttemplate <class _Compare, class _InputIterator1, class _InputIterator2>
55461b9a4ffdSMarshall Clow_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
55473e519524SHoward Hinnant__lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
55483e519524SHoward Hinnant                          _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
55493e519524SHoward Hinnant{
5550910285b2SEric Fiselier    for (; __first2 != __last2; ++__first1, (void) ++__first2)
55513e519524SHoward Hinnant    {
55523e519524SHoward Hinnant        if (__first1 == __last1 || __comp(*__first1, *__first2))
55533e519524SHoward Hinnant            return true;
55543e519524SHoward Hinnant        if (__comp(*__first2, *__first1))
55553e519524SHoward Hinnant            return false;
55563e519524SHoward Hinnant    }
55573e519524SHoward Hinnant    return false;
55583e519524SHoward Hinnant}
55593e519524SHoward Hinnant
55603e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2, class _Compare>
55611362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
55621362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
55633e519524SHoward Hinnantbool
55643e519524SHoward Hinnantlexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
55653e519524SHoward Hinnant                        _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
55663e519524SHoward Hinnant{
5567aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
55683e519524SHoward Hinnant    return __lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
55693e519524SHoward Hinnant}
55703e519524SHoward Hinnant
55713e519524SHoward Hinnanttemplate <class _InputIterator1, class _InputIterator2>
55721362d7efSNico Weber_LIBCPP_NODISCARD_EXT inline
55731362d7efSNico Weber_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
55743e519524SHoward Hinnantbool
55753e519524SHoward Hinnantlexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
55763e519524SHoward Hinnant                        _InputIterator2 __first2, _InputIterator2 __last2)
55773e519524SHoward Hinnant{
5578ce48a113SHoward Hinnant    return _VSTD::lexicographical_compare(__first1, __last1, __first2, __last2,
55793e519524SHoward Hinnant                                         __less<typename iterator_traits<_InputIterator1>::value_type,
55803e519524SHoward Hinnant                                                typename iterator_traits<_InputIterator2>::value_type>());
55813e519524SHoward Hinnant}
55823e519524SHoward Hinnant
55833e519524SHoward Hinnant// next_permutation
55843e519524SHoward Hinnant
55853e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
55863e519524SHoward Hinnantbool
55873e519524SHoward Hinnant__next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
55883e519524SHoward Hinnant{
55893e519524SHoward Hinnant    _BidirectionalIterator __i = __last;
55903e519524SHoward Hinnant    if (__first == __last || __first == --__i)
55913e519524SHoward Hinnant        return false;
55923e519524SHoward Hinnant    while (true)
55933e519524SHoward Hinnant    {
55943e519524SHoward Hinnant        _BidirectionalIterator __ip1 = __i;
55953e519524SHoward Hinnant        if (__comp(*--__i, *__ip1))
55963e519524SHoward Hinnant        {
55973e519524SHoward Hinnant            _BidirectionalIterator __j = __last;
55983e519524SHoward Hinnant            while (!__comp(*__i, *--__j))
55993e519524SHoward Hinnant                ;
56003e519524SHoward Hinnant            swap(*__i, *__j);
5601ce48a113SHoward Hinnant            _VSTD::reverse(__ip1, __last);
56023e519524SHoward Hinnant            return true;
56033e519524SHoward Hinnant        }
56043e519524SHoward Hinnant        if (__i == __first)
56053e519524SHoward Hinnant        {
5606ce48a113SHoward Hinnant            _VSTD::reverse(__first, __last);
56073e519524SHoward Hinnant            return false;
56083e519524SHoward Hinnant        }
56093e519524SHoward Hinnant    }
56103e519524SHoward Hinnant}
56113e519524SHoward Hinnant
56123e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _Compare>
56133e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
56143e519524SHoward Hinnantbool
56153e519524SHoward Hinnantnext_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
56163e519524SHoward Hinnant{
5617aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
56183e519524SHoward Hinnant    return __next_permutation<_Comp_ref>(__first, __last, __comp);
56193e519524SHoward Hinnant}
56203e519524SHoward Hinnant
56213e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
56223e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
56233e519524SHoward Hinnantbool
56243e519524SHoward Hinnantnext_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
56253e519524SHoward Hinnant{
5626ce48a113SHoward Hinnant    return _VSTD::next_permutation(__first, __last,
56273e519524SHoward Hinnant                                  __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
56283e519524SHoward Hinnant}
56293e519524SHoward Hinnant
56303e519524SHoward Hinnant// prev_permutation
56313e519524SHoward Hinnant
56323e519524SHoward Hinnanttemplate <class _Compare, class _BidirectionalIterator>
56333e519524SHoward Hinnantbool
56343e519524SHoward Hinnant__prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
56353e519524SHoward Hinnant{
56363e519524SHoward Hinnant    _BidirectionalIterator __i = __last;
56373e519524SHoward Hinnant    if (__first == __last || __first == --__i)
56383e519524SHoward Hinnant        return false;
56393e519524SHoward Hinnant    while (true)
56403e519524SHoward Hinnant    {
56413e519524SHoward Hinnant        _BidirectionalIterator __ip1 = __i;
56423e519524SHoward Hinnant        if (__comp(*__ip1, *--__i))
56433e519524SHoward Hinnant        {
56443e519524SHoward Hinnant            _BidirectionalIterator __j = __last;
56453e519524SHoward Hinnant            while (!__comp(*--__j, *__i))
56463e519524SHoward Hinnant                ;
56473e519524SHoward Hinnant            swap(*__i, *__j);
5648ce48a113SHoward Hinnant            _VSTD::reverse(__ip1, __last);
56493e519524SHoward Hinnant            return true;
56503e519524SHoward Hinnant        }
56513e519524SHoward Hinnant        if (__i == __first)
56523e519524SHoward Hinnant        {
5653ce48a113SHoward Hinnant            _VSTD::reverse(__first, __last);
56543e519524SHoward Hinnant            return false;
56553e519524SHoward Hinnant        }
56563e519524SHoward Hinnant    }
56573e519524SHoward Hinnant}
56583e519524SHoward Hinnant
56593e519524SHoward Hinnanttemplate <class _BidirectionalIterator, class _Compare>
56603e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
56613e519524SHoward Hinnantbool
56623e519524SHoward Hinnantprev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
56633e519524SHoward Hinnant{
5664aa1cad15SEric Fiselier    typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
56653e519524SHoward Hinnant    return __prev_permutation<_Comp_ref>(__first, __last, __comp);
56663e519524SHoward Hinnant}
56673e519524SHoward Hinnant
56683e519524SHoward Hinnanttemplate <class _BidirectionalIterator>
56693e519524SHoward Hinnantinline _LIBCPP_INLINE_VISIBILITY
56703e519524SHoward Hinnantbool
56713e519524SHoward Hinnantprev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
56723e519524SHoward Hinnant{
5673ce48a113SHoward Hinnant    return _VSTD::prev_permutation(__first, __last,
56743e519524SHoward Hinnant                                  __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
56753e519524SHoward Hinnant}
56763e519524SHoward Hinnant
56773e519524SHoward Hinnant_LIBCPP_END_NAMESPACE_STD
56783e519524SHoward Hinnant
5679a016efb1SEric Fiselier_LIBCPP_POP_MACROS
5680a016efb1SEric Fiselier
56810a06eb91SLouis Dionne#if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
568295689243SLouis Dionne#   include <__pstl_algorithm>
56830a06eb91SLouis Dionne#endif
56840a06eb91SLouis Dionne
56853e519524SHoward Hinnant#endif  // _LIBCPP_ALGORITHM
5686