1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_ALGORITHM
11#define _LIBCPP_ALGORITHM
12
13/*
14    algorithm synopsis
15
16#include <initializer_list>
17
18namespace std
19{
20
21namespace ranges {
22  template <class I, class F>
23    struct in_fun_result;     // since C++20
24
25  template <class I1, class I2>
26    struct in_in_result;      // since C++20
27
28  template <class I1, class I2, class O>
29    struct in_in_out_result;  // since C++20
30
31  template <class I, class O1, class O2>
32    struct in_out_out_result; // since C++20
33
34  template <class I1, class I2>
35    struct min_max_result;    // since C++20
36
37  template <class I>
38    struct in_found_result;   // since C++20
39
40  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
41    indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>             // since C++20
42  constexpr I min_element(I first, S last, Comp comp = {}, Proj proj = {});
43
44  template<forward_range R, class Proj = identity,
45    indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less> // since C++20
46  constexpr borrowed_iterator_t<R> min_element(R&& r, Comp comp = {}, Proj proj = {});
47
48  template <input_iterator I1, sentinel_for<_I1> S1, input_iterator I2, sentinel_for<_I2> S2,
49          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
50    requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
51  constexpr mismatch_result<_I1, _I2>
52  mismatch()(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {}) // since C++20
53
54  template <input_range R1, input_range R2,
55          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
56    requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
57  constexpr mismatch_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
58  mismatch(R1&& r1, R2&& r2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {})                           // since C++20
59
60    requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
61    constexpr I find(I first, S last, const T& value, Proj proj = {});              // since C++20
62
63  template<input_range R, class T, class Proj = identity>
64    requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
65    constexpr borrowed_iterator_t<R>
66      find(R&& r, const T& value, Proj proj = {});                                  // since C++20
67
68  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
69           indirect_unary_predicate<projected<I, Proj>> Pred>
70    constexpr I find_if(I first, S last, Pred pred, Proj proj = {});                // since C++20
71
72  template<input_range R, class Proj = identity,
73           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
74    constexpr borrowed_iterator_t<R>
75      find_if(R&& r, Pred pred, Proj proj = {});                                    // since C++20
76
77  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
78           indirect_unary_predicate<projected<I, Proj>> Pred>
79    constexpr I find_if_not(I first, S last, Pred pred, Proj proj = {});            // since C++20
80
81  template<input_range R, class Proj = identity,
82           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
83    constexpr borrowed_iterator_t<R>
84      find_if_not(R&& r, Pred pred, Proj proj = {});                                // since C++20
85
86  template<class T, class Proj = identity,
87           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
88    constexpr const T& min(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
89
90  template<copyable T, class Proj = identity,
91           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
92    constexpr T min(initializer_list<T> r, Comp comp = {}, Proj proj = {});         // since C++20
93
94 template<input_range R, class Proj = identity,
95          indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
96   requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
97   constexpr range_value_t<R>
98     min(R&& r, Comp comp = {}, Proj proj = {});                                    // since C++20
99
100  template<class T, class Proj = identity,
101           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
102    constexpr const T& max(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
103
104  template<copyable T, class Proj = identity,
105           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
106    constexpr T max(initializer_list<T> r, Comp comp = {}, Proj proj = {});         // since C++20
107
108  template<input_range R, class Proj = identity,
109           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
110    requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
111    constexpr range_value_t<R>
112      max(R&& r, Comp comp = {}, Proj proj = {});                                   // since C++20
113
114  template<class I, class O>
115    using unary_transform_result = in_out_result<I, O>;                             // since C++20
116
117  template<class I1, class I2, class O>
118    using binary_transform_result = in_in_out_result<I1, I2, O>;                    // since C++20
119
120  template<input_iterator I, sentinel_for<I> S, weakly_incrementable O,
121           copy_constructible F, class Proj = identity>
122    requires indirectly_writable<O, indirect_result_t<F&, projected<I, Proj>>>
123    constexpr ranges::unary_transform_result<I, O>
124      transform(I first1, S last1, O result, F op, Proj proj = {});                 // since C++20
125
126  template<input_range R, weakly_incrementable O, copy_constructible F,
127           class Proj = identity>
128    requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R>, Proj>>>
129    constexpr ranges::unary_transform_result<borrowed_iterator_t<R>, O>
130      transform(R&& r, O result, F op, Proj proj = {});                             // since C++20
131
132  template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
133           weakly_incrementable O, copy_constructible F, class Proj1 = identity,
134           class Proj2 = identity>
135    requires indirectly_writable<O, indirect_result_t<F&, projected<I1, Proj1>,
136                                           projected<I2, Proj2>>>
137    constexpr ranges::binary_transform_result<I1, I2, O>
138      transform(I1 first1, S1 last1, I2 first2, S2 last2, O result,
139                        F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {});           // since C++20
140
141  template<input_range R1, input_range R2, weakly_incrementable O,
142           copy_constructible F, class Proj1 = identity, class Proj2 = identity>
143    requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R1>, Proj1>,
144                                           projected<iterator_t<R2>, Proj2>>>
145    constexpr ranges::binary_transform_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
146      transform(R1&& r1, R2&& r2, O result,
147                        F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {});           // since C++20
148
149  template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity>
150    requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
151    constexpr iter_difference_t<I>
152      count(I first, S last, const T& value, Proj proj = {});                       // since C++20
153
154  template<input_range R, class T, class Proj = identity>
155    requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
156    constexpr range_difference_t<R>
157      count(R&& r, const T& value, Proj proj = {});                                 // since C++20
158
159  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
160           indirect_unary_predicate<projected<I, Proj>> Pred>
161    constexpr iter_difference_t<I>
162      count_if(I first, S last, Pred pred, Proj proj = {});                         // since C++20
163
164  template<input_range R, class Proj = identity,
165           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
166    constexpr range_difference_t<R>
167      count_if(R&& r, Pred pred, Proj proj = {});                                   // since C++20
168
169  template<class T, class Proj = identity,
170           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
171    constexpr ranges::minmax_result<const T&>
172      minmax(const T& a, const T& b, Comp comp = {}, Proj proj = {});                     // since C++20
173
174  template<copyable T, class Proj = identity,
175           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
176    constexpr ranges::minmax_result<T>
177      minmax(initializer_list<T> r, Comp comp = {}, Proj proj = {});                      // since C++20
178
179  template<input_range R, class Proj = identity,
180           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
181    requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
182    constexpr ranges::minmax_result<range_value_t<R>>
183      minmax(R&& r, Comp comp = {}, Proj proj = {});                                      // since C++20
184
185  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
186           indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
187    constexpr ranges::minmax_element_result<I>
188      minmax_element(I first, S last, Comp comp = {}, Proj proj = {});                    // since C++20
189
190  template<forward_range R, class Proj = identity,
191           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
192    constexpr ranges::minmax_element_result<borrowed_iterator_t<R>>
193      minmax_element(R&& r, Comp comp = {}, Proj proj = {});                              // since C++20
194}
195
196    constexpr bool     // constexpr in C++20
197    all_of(InputIterator first, InputIterator last, Predicate pred);
198
199template <class InputIterator, class Predicate>
200    constexpr bool     // constexpr in C++20
201    any_of(InputIterator first, InputIterator last, Predicate pred);
202
203template <class InputIterator, class Predicate>
204    constexpr bool     // constexpr in C++20
205    none_of(InputIterator first, InputIterator last, Predicate pred);
206
207template <class InputIterator, class Function>
208    constexpr Function          // constexpr in C++20
209    for_each(InputIterator first, InputIterator last, Function f);
210
211template<class InputIterator, class Size, class Function>
212    constexpr InputIterator     // constexpr in C++20
213    for_each_n(InputIterator first, Size n, Function f); // C++17
214
215template <class InputIterator, class T>
216    constexpr InputIterator     // constexpr in C++20
217    find(InputIterator first, InputIterator last, const T& value);
218
219template <class InputIterator, class Predicate>
220    constexpr InputIterator     // constexpr in C++20
221    find_if(InputIterator first, InputIterator last, Predicate pred);
222
223template<class InputIterator, class Predicate>
224    constexpr InputIterator     // constexpr in C++20
225    find_if_not(InputIterator first, InputIterator last, Predicate pred);
226
227template <class ForwardIterator1, class ForwardIterator2>
228    constexpr ForwardIterator1  // constexpr in C++20
229    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
230             ForwardIterator2 first2, ForwardIterator2 last2);
231
232template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
233    constexpr ForwardIterator1  // constexpr in C++20
234    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
235             ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
236
237template <class ForwardIterator1, class ForwardIterator2>
238    constexpr ForwardIterator1  // constexpr in C++20
239    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
240                  ForwardIterator2 first2, ForwardIterator2 last2);
241
242template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
243    constexpr ForwardIterator1  // constexpr in C++20
244    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
245                  ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
246
247template <class ForwardIterator>
248    constexpr ForwardIterator   // constexpr in C++20
249    adjacent_find(ForwardIterator first, ForwardIterator last);
250
251template <class ForwardIterator, class BinaryPredicate>
252    constexpr ForwardIterator   // constexpr in C++20
253    adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
254
255template <class InputIterator, class T>
256    constexpr typename iterator_traits<InputIterator>::difference_type  // constexpr in C++20
257    count(InputIterator first, InputIterator last, const T& value);
258
259template <class InputIterator, class Predicate>
260    constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
261    count_if(InputIterator first, InputIterator last, Predicate pred);
262
263template <class InputIterator1, class InputIterator2>
264    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
265    mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
266
267template <class InputIterator1, class InputIterator2>
268    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
269    mismatch(InputIterator1 first1, InputIterator1 last1,
270             InputIterator2 first2, InputIterator2 last2); // **C++14**
271
272template <class InputIterator1, class InputIterator2, class BinaryPredicate>
273    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
274    mismatch(InputIterator1 first1, InputIterator1 last1,
275             InputIterator2 first2, BinaryPredicate pred);
276
277template <class InputIterator1, class InputIterator2, class BinaryPredicate>
278    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
279    mismatch(InputIterator1 first1, InputIterator1 last1,
280             InputIterator2 first2, InputIterator2 last2,
281             BinaryPredicate pred); // **C++14**
282
283template <class InputIterator1, class InputIterator2>
284    constexpr bool      // constexpr in C++20
285    equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
286
287template <class InputIterator1, class InputIterator2>
288    constexpr bool      // constexpr in C++20
289    equal(InputIterator1 first1, InputIterator1 last1,
290          InputIterator2 first2, InputIterator2 last2); // **C++14**
291
292template <class InputIterator1, class InputIterator2, class BinaryPredicate>
293    constexpr bool      // constexpr in C++20
294    equal(InputIterator1 first1, InputIterator1 last1,
295          InputIterator2 first2, BinaryPredicate pred);
296
297template <class InputIterator1, class InputIterator2, class BinaryPredicate>
298    constexpr bool      // constexpr in C++20
299    equal(InputIterator1 first1, InputIterator1 last1,
300          InputIterator2 first2, InputIterator2 last2,
301          BinaryPredicate pred); // **C++14**
302
303template<class ForwardIterator1, class ForwardIterator2>
304    constexpr bool      // constexpr in C++20
305    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
306                   ForwardIterator2 first2);
307
308template<class ForwardIterator1, class ForwardIterator2>
309    constexpr bool      // constexpr in C++20
310    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
311                   ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
312
313template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
314    constexpr bool      // constexpr in C++20
315    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
316                   ForwardIterator2 first2, BinaryPredicate pred);
317
318template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
319    constexpr bool      // constexpr in C++20
320    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
321                   ForwardIterator2 first2, ForwardIterator2 last2,
322                   BinaryPredicate pred);  // **C++14**
323
324template <class ForwardIterator1, class ForwardIterator2>
325    constexpr ForwardIterator1      // constexpr in C++20
326    search(ForwardIterator1 first1, ForwardIterator1 last1,
327           ForwardIterator2 first2, ForwardIterator2 last2);
328
329template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
330    constexpr ForwardIterator1      // constexpr in C++20
331    search(ForwardIterator1 first1, ForwardIterator1 last1,
332           ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
333
334template <class ForwardIterator, class Size, class T>
335    constexpr ForwardIterator       // constexpr in C++20
336    search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
337
338template <class ForwardIterator, class Size, class T, class BinaryPredicate>
339    constexpr ForwardIterator       // constexpr in C++20
340    search_n(ForwardIterator first, ForwardIterator last,
341             Size count, const T& value, BinaryPredicate pred);
342
343template <class InputIterator, class OutputIterator>
344    constexpr OutputIterator      // constexpr in C++20
345    copy(InputIterator first, InputIterator last, OutputIterator result);
346
347template<class InputIterator, class OutputIterator, class Predicate>
348    constexpr OutputIterator      // constexpr in C++20
349    copy_if(InputIterator first, InputIterator last,
350            OutputIterator result, Predicate pred);
351
352template<class InputIterator, class Size, class OutputIterator>
353    constexpr OutputIterator      // constexpr in C++20
354    copy_n(InputIterator first, Size n, OutputIterator result);
355
356template <class BidirectionalIterator1, class BidirectionalIterator2>
357    constexpr BidirectionalIterator2      // constexpr in C++20
358    copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
359                  BidirectionalIterator2 result);
360
361template <class ForwardIterator1, class ForwardIterator2>
362    constexpr ForwardIterator2    // constexpr in C++20
363    swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
364
365template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2>
366        requires indirectly_swappable<I1, I2>
367    constexpr ranges::swap_ranges_result<I1, I2>
368        ranges::swap_ranges(I1 first1, S1 last1, I2 first2, S2 last2);
369
370template<input_range R1, input_range R2>
371        requires indirectly_swappable<iterator_t<R1>, iterator_t<R2>>
372    constexpr ranges::swap_ranges_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
373        ranges::swap_ranges(R1&& r1, R2&& r2);
374
375template <class ForwardIterator1, class ForwardIterator2>
376    constexpr void                // constexpr in C++20
377    iter_swap(ForwardIterator1 a, ForwardIterator2 b);
378
379template <class InputIterator, class OutputIterator, class UnaryOperation>
380    constexpr OutputIterator      // constexpr in C++20
381    transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
382
383template <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
384    constexpr OutputIterator      // constexpr in C++20
385    transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
386              OutputIterator result, BinaryOperation binary_op);
387
388template <class ForwardIterator, class T>
389    constexpr void      // constexpr in C++20
390    replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
391
392template <class ForwardIterator, class Predicate, class T>
393    constexpr void      // constexpr in C++20
394    replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
395
396template <class InputIterator, class OutputIterator, class T>
397    constexpr OutputIterator      // constexpr in C++20
398    replace_copy(InputIterator first, InputIterator last, OutputIterator result,
399                 const T& old_value, const T& new_value);
400
401template <class InputIterator, class OutputIterator, class Predicate, class T>
402    constexpr OutputIterator      // constexpr in C++20
403    replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
404
405template <class ForwardIterator, class T>
406    constexpr void      // constexpr in C++20
407    fill(ForwardIterator first, ForwardIterator last, const T& value);
408
409template <class OutputIterator, class Size, class T>
410    constexpr OutputIterator      // constexpr in C++20
411    fill_n(OutputIterator first, Size n, const T& value);
412
413template <class ForwardIterator, class Generator>
414    constexpr void      // constexpr in C++20
415    generate(ForwardIterator first, ForwardIterator last, Generator gen);
416
417template <class OutputIterator, class Size, class Generator>
418    constexpr OutputIterator      // constexpr in C++20
419    generate_n(OutputIterator first, Size n, Generator gen);
420
421template <class ForwardIterator, class T>
422    constexpr ForwardIterator     // constexpr in C++20
423    remove(ForwardIterator first, ForwardIterator last, const T& value);
424
425template <class ForwardIterator, class Predicate>
426    constexpr ForwardIterator     // constexpr in C++20
427    remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
428
429template <class InputIterator, class OutputIterator, class T>
430    constexpr OutputIterator     // constexpr in C++20
431    remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
432
433template <class InputIterator, class OutputIterator, class Predicate>
434    constexpr OutputIterator     // constexpr in C++20
435    remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
436
437template <class ForwardIterator>
438    constexpr ForwardIterator    // constexpr in C++20
439    unique(ForwardIterator first, ForwardIterator last);
440
441template <class ForwardIterator, class BinaryPredicate>
442    constexpr ForwardIterator    // constexpr in C++20
443    unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
444
445template <class InputIterator, class OutputIterator>
446    constexpr OutputIterator     // constexpr in C++20
447    unique_copy(InputIterator first, InputIterator last, OutputIterator result);
448
449template <class InputIterator, class OutputIterator, class BinaryPredicate>
450    constexpr OutputIterator     // constexpr in C++20
451    unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
452
453template <class BidirectionalIterator>
454    constexpr void               // constexpr in C++20
455    reverse(BidirectionalIterator first, BidirectionalIterator last);
456
457template <class BidirectionalIterator, class OutputIterator>
458    constexpr OutputIterator       // constexpr in C++20
459    reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
460
461template <class ForwardIterator>
462    constexpr ForwardIterator      // constexpr in C++20
463    rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
464
465template <class ForwardIterator, class OutputIterator>
466    constexpr OutputIterator       // constexpr in C++20
467    rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
468
469template <class RandomAccessIterator>
470    void
471    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
472
473template <class RandomAccessIterator, class RandomNumberGenerator>
474    void
475    random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
476                   RandomNumberGenerator& rand);  // deprecated in C++14, removed in C++17
477
478template<class PopulationIterator, class SampleIterator,
479         class Distance, class UniformRandomBitGenerator>
480    SampleIterator sample(PopulationIterator first, PopulationIterator last,
481                          SampleIterator out, Distance n,
482                          UniformRandomBitGenerator&& g); // C++17
483
484template<class RandomAccessIterator, class UniformRandomNumberGenerator>
485    void shuffle(RandomAccessIterator first, RandomAccessIterator last,
486                 UniformRandomNumberGenerator&& g);
487
488template<class ForwardIterator>
489  constexpr ForwardIterator
490    shift_left(ForwardIterator first, ForwardIterator last,
491               typename iterator_traits<ForwardIterator>::difference_type n); // C++20
492
493template<class ForwardIterator>
494  constexpr ForwardIterator
495    shift_right(ForwardIterator first, ForwardIterator last,
496                typename iterator_traits<ForwardIterator>::difference_type n); // C++20
497
498template <class InputIterator, class Predicate>
499    constexpr bool  // constexpr in C++20
500    is_partitioned(InputIterator first, InputIterator last, Predicate pred);
501
502template <class ForwardIterator, class Predicate>
503    constexpr ForwardIterator  // constexpr in C++20
504    partition(ForwardIterator first, ForwardIterator last, Predicate pred);
505
506template <class InputIterator, class OutputIterator1,
507          class OutputIterator2, class Predicate>
508    constexpr pair<OutputIterator1, OutputIterator2>   // constexpr in C++20
509    partition_copy(InputIterator first, InputIterator last,
510                   OutputIterator1 out_true, OutputIterator2 out_false,
511                   Predicate pred);
512
513template <class ForwardIterator, class Predicate>
514    ForwardIterator
515    stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
516
517template<class ForwardIterator, class Predicate>
518    constexpr ForwardIterator  // constexpr in C++20
519    partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
520
521template <class ForwardIterator>
522    constexpr bool  // constexpr in C++20
523    is_sorted(ForwardIterator first, ForwardIterator last);
524
525template <class ForwardIterator, class Compare>
526    constexpr bool  // constexpr in C++20
527    is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
528
529template<class ForwardIterator>
530    constexpr ForwardIterator    // constexpr in C++20
531    is_sorted_until(ForwardIterator first, ForwardIterator last);
532
533template <class ForwardIterator, class Compare>
534    constexpr ForwardIterator    // constexpr in C++20
535    is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
536
537template <class RandomAccessIterator>
538    constexpr void               // constexpr in C++20
539    sort(RandomAccessIterator first, RandomAccessIterator last);
540
541template <class RandomAccessIterator, class Compare>
542    constexpr void               // constexpr in C++20
543    sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
544
545template <class RandomAccessIterator>
546    void
547    stable_sort(RandomAccessIterator first, RandomAccessIterator last);
548
549template <class RandomAccessIterator, class Compare>
550    void
551    stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
552
553template <class RandomAccessIterator>
554    constexpr void                    // constexpr in C++20
555    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
556
557template <class RandomAccessIterator, class Compare>
558    constexpr void                    // constexpr in C++20
559    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
560
561template <class InputIterator, class RandomAccessIterator>
562    constexpr RandomAccessIterator    // constexpr in C++20
563    partial_sort_copy(InputIterator first, InputIterator last,
564                      RandomAccessIterator result_first, RandomAccessIterator result_last);
565
566template <class InputIterator, class RandomAccessIterator, class Compare>
567    constexpr RandomAccessIterator    // constexpr in C++20
568    partial_sort_copy(InputIterator first, InputIterator last,
569                      RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
570
571template <class RandomAccessIterator>
572    constexpr void                    // constexpr in C++20
573    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
574
575template <class RandomAccessIterator, class Compare>
576    constexpr void                    // constexpr in C++20
577    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
578
579template <class ForwardIterator, class T>
580    constexpr ForwardIterator                         // constexpr in C++20
581    lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
582
583template <class ForwardIterator, class T, class Compare>
584    constexpr ForwardIterator                         // constexpr in C++20
585    lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
586
587template <class ForwardIterator, class T>
588    constexpr ForwardIterator                         // constexpr in C++20
589    upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
590
591template <class ForwardIterator, class T, class Compare>
592    constexpr ForwardIterator                         // constexpr in C++20
593    upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
594
595template <class ForwardIterator, class T>
596    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
597    equal_range(ForwardIterator first, ForwardIterator last, const T& value);
598
599template <class ForwardIterator, class T, class Compare>
600    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
601    equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
602
603template <class ForwardIterator, class T>
604    constexpr bool                                    // constexpr in C++20
605    binary_search(ForwardIterator first, ForwardIterator last, const T& value);
606
607template <class ForwardIterator, class T, class Compare>
608    constexpr bool                                    // constexpr in C++20
609    binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
610
611template <class InputIterator1, class InputIterator2, class OutputIterator>
612    constexpr OutputIterator                          // constexpr in C++20
613    merge(InputIterator1 first1, InputIterator1 last1,
614          InputIterator2 first2, InputIterator2 last2, OutputIterator result);
615
616template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
617    constexpr OutputIterator                          // constexpr in C++20
618    merge(InputIterator1 first1, InputIterator1 last1,
619          InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
620
621template <class BidirectionalIterator>
622    void
623    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
624
625template <class BidirectionalIterator, class Compare>
626    void
627    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
628
629template <class InputIterator1, class InputIterator2>
630    constexpr bool                                    // constexpr in C++20
631    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
632
633template <class InputIterator1, class InputIterator2, class Compare>
634    constexpr bool                                    // constexpr in C++20
635    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
636
637template <class InputIterator1, class InputIterator2, class OutputIterator>
638    constexpr OutputIterator                          // constexpr in C++20
639    set_union(InputIterator1 first1, InputIterator1 last1,
640              InputIterator2 first2, InputIterator2 last2, OutputIterator result);
641
642template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
643    constexpr OutputIterator                          // constexpr in C++20
644    set_union(InputIterator1 first1, InputIterator1 last1,
645              InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
646
647template <class InputIterator1, class InputIterator2, class OutputIterator>
648    constexpr OutputIterator                         // constexpr in C++20
649    set_intersection(InputIterator1 first1, InputIterator1 last1,
650                     InputIterator2 first2, InputIterator2 last2, OutputIterator result);
651
652template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
653    constexpr OutputIterator                         // constexpr in C++20
654    set_intersection(InputIterator1 first1, InputIterator1 last1,
655                     InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
656
657template <class InputIterator1, class InputIterator2, class OutputIterator>
658    constexpr OutputIterator                         // constexpr in C++20
659    set_difference(InputIterator1 first1, InputIterator1 last1,
660                   InputIterator2 first2, InputIterator2 last2, OutputIterator result);
661
662template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
663    constexpr OutputIterator                         // constexpr in C++20
664    set_difference(InputIterator1 first1, InputIterator1 last1,
665                   InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
666
667template <class InputIterator1, class InputIterator2, class OutputIterator>
668    constexpr OutputIterator                         // constexpr in C++20
669    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
670                             InputIterator2 first2, InputIterator2 last2, OutputIterator result);
671
672template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
673    constexpr OutputIterator                         // constexpr in C++20
674    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
675                             InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
676
677template <class RandomAccessIterator>
678    constexpr void                                   // constexpr in C++20
679    push_heap(RandomAccessIterator first, RandomAccessIterator last);
680
681template <class RandomAccessIterator, class Compare>
682    constexpr void                                   // constexpr in C++20
683    push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
684
685template <class RandomAccessIterator>
686    constexpr void                                   // constexpr in C++20
687    pop_heap(RandomAccessIterator first, RandomAccessIterator last);
688
689template <class RandomAccessIterator, class Compare>
690    constexpr void                                   // constexpr in C++20
691    pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
692
693template <class RandomAccessIterator>
694    constexpr void                                   // constexpr in C++20
695    make_heap(RandomAccessIterator first, RandomAccessIterator last);
696
697template <class RandomAccessIterator, class Compare>
698    constexpr void                                   // constexpr in C++20
699    make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
700
701template <class RandomAccessIterator>
702    constexpr void                                   // constexpr in C++20
703    sort_heap(RandomAccessIterator first, RandomAccessIterator last);
704
705template <class RandomAccessIterator, class Compare>
706    constexpr void                                   // constexpr in C++20
707    sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
708
709template <class RandomAccessIterator>
710    constexpr bool   // constexpr in C++20
711    is_heap(RandomAccessIterator first, RandomAccessiterator last);
712
713template <class RandomAccessIterator, class Compare>
714    constexpr bool   // constexpr in C++20
715    is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
716
717template <class RandomAccessIterator>
718    constexpr RandomAccessIterator   // constexpr in C++20
719    is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
720
721template <class RandomAccessIterator, class Compare>
722    constexpr RandomAccessIterator   // constexpr in C++20
723    is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
724
725template <class ForwardIterator>
726    constexpr ForwardIterator        // constexpr in C++14
727    min_element(ForwardIterator first, ForwardIterator last);
728
729template <class ForwardIterator, class Compare>
730    constexpr ForwardIterator        // constexpr in C++14
731    min_element(ForwardIterator first, ForwardIterator last, Compare comp);
732
733template <class T>
734    constexpr const T&               // constexpr in C++14
735    min(const T& a, const T& b);
736
737template <class T, class Compare>
738    constexpr const T&               // constexpr in C++14
739    min(const T& a, const T& b, Compare comp);
740
741template<class T>
742    constexpr T                      // constexpr in C++14
743    min(initializer_list<T> t);
744
745template<class T, class Compare>
746    constexpr T                      // constexpr in C++14
747    min(initializer_list<T> t, Compare comp);
748
749template<class T>
750    constexpr const T& clamp(const T& v, const T& lo, const T& hi);               // C++17
751
752template<class T, class Compare>
753    constexpr const T& clamp(const T& v, const T& lo, const T& hi, Compare comp); // C++17
754
755template <class ForwardIterator>
756    constexpr ForwardIterator        // constexpr in C++14
757    max_element(ForwardIterator first, ForwardIterator last);
758
759template <class ForwardIterator, class Compare>
760    constexpr ForwardIterator        // constexpr in C++14
761    max_element(ForwardIterator first, ForwardIterator last, Compare comp);
762
763template <class T>
764    constexpr const T&               // constexpr in C++14
765    max(const T& a, const T& b);
766
767template <class T, class Compare>
768    constexpr const T&               // constexpr in C++14
769    max(const T& a, const T& b, Compare comp);
770
771template<class T>
772    constexpr T                      // constexpr in C++14
773    max(initializer_list<T> t);
774
775template<class T, class Compare>
776    constexpr T                      // constexpr in C++14
777    max(initializer_list<T> t, Compare comp);
778
779template<class ForwardIterator>
780    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++14
781    minmax_element(ForwardIterator first, ForwardIterator last);
782
783template<class ForwardIterator, class Compare>
784    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++14
785    minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);
786
787template<class T>
788    constexpr pair<const T&, const T&>  // constexpr in C++14
789    minmax(const T& a, const T& b);
790
791template<class T, class Compare>
792    constexpr pair<const T&, const T&>  // constexpr in C++14
793    minmax(const T& a, const T& b, Compare comp);
794
795template<class T>
796    constexpr pair<T, T>                // constexpr in C++14
797    minmax(initializer_list<T> t);
798
799template<class T, class Compare>
800    constexpr pair<T, T>                // constexpr in C++14
801    minmax(initializer_list<T> t, Compare comp);
802
803template <class InputIterator1, class InputIterator2>
804    constexpr bool     // constexpr in C++20
805    lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
806
807template <class InputIterator1, class InputIterator2, class Compare>
808    constexpr bool     // constexpr in C++20
809    lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
810                            InputIterator2 first2, InputIterator2 last2, Compare comp);
811
812template <class BidirectionalIterator>
813    constexpr bool     // constexpr in C++20
814    next_permutation(BidirectionalIterator first, BidirectionalIterator last);
815
816template <class BidirectionalIterator, class Compare>
817    constexpr bool     // constexpr in C++20
818    next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
819
820template <class BidirectionalIterator>
821    constexpr bool     // constexpr in C++20
822    prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
823
824template <class BidirectionalIterator, class Compare>
825    constexpr bool     // constexpr in C++20
826    prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
827}  // std
828
829*/
830
831#include <__assert> // all public C++ headers provide the assertion handler
832#include <__bits>
833#include <__config>
834#include <__debug>
835#include <cstddef>
836#include <cstring>
837#include <functional>
838#include <initializer_list>
839#include <iterator>
840#include <memory>
841#include <type_traits>
842#include <version>
843
844#include <__algorithm/adjacent_find.h>
845#include <__algorithm/all_of.h>
846#include <__algorithm/any_of.h>
847#include <__algorithm/binary_search.h>
848#include <__algorithm/clamp.h>
849#include <__algorithm/comp.h>
850#include <__algorithm/comp_ref_type.h>
851#include <__algorithm/copy.h>
852#include <__algorithm/copy_backward.h>
853#include <__algorithm/copy_if.h>
854#include <__algorithm/copy_n.h>
855#include <__algorithm/count.h>
856#include <__algorithm/count_if.h>
857#include <__algorithm/equal.h>
858#include <__algorithm/equal_range.h>
859#include <__algorithm/fill.h>
860#include <__algorithm/fill_n.h>
861#include <__algorithm/find.h>
862#include <__algorithm/find_end.h>
863#include <__algorithm/find_first_of.h>
864#include <__algorithm/find_if.h>
865#include <__algorithm/find_if_not.h>
866#include <__algorithm/for_each.h>
867#include <__algorithm/for_each_n.h>
868#include <__algorithm/generate.h>
869#include <__algorithm/generate_n.h>
870#include <__algorithm/half_positive.h>
871#include <__algorithm/in_found_result.h>
872#include <__algorithm/in_fun_result.h>
873#include <__algorithm/in_in_out_result.h>
874#include <__algorithm/in_in_result.h>
875#include <__algorithm/in_out_out_result.h>
876#include <__algorithm/in_out_result.h>
877#include <__algorithm/includes.h>
878#include <__algorithm/inplace_merge.h>
879#include <__algorithm/is_heap.h>
880#include <__algorithm/is_heap_until.h>
881#include <__algorithm/is_partitioned.h>
882#include <__algorithm/is_permutation.h>
883#include <__algorithm/is_sorted.h>
884#include <__algorithm/is_sorted_until.h>
885#include <__algorithm/iter_swap.h>
886#include <__algorithm/lexicographical_compare.h>
887#include <__algorithm/lower_bound.h>
888#include <__algorithm/make_heap.h>
889#include <__algorithm/max.h>
890#include <__algorithm/max_element.h>
891#include <__algorithm/merge.h>
892#include <__algorithm/min.h>
893#include <__algorithm/min_element.h>
894#include <__algorithm/min_max_result.h>
895#include <__algorithm/minmax.h>
896#include <__algorithm/minmax_element.h>
897#include <__algorithm/mismatch.h>
898#include <__algorithm/move.h>
899#include <__algorithm/move_backward.h>
900#include <__algorithm/next_permutation.h>
901#include <__algorithm/none_of.h>
902#include <__algorithm/nth_element.h>
903#include <__algorithm/partial_sort.h>
904#include <__algorithm/partial_sort_copy.h>
905#include <__algorithm/partition.h>
906#include <__algorithm/partition_copy.h>
907#include <__algorithm/partition_point.h>
908#include <__algorithm/pop_heap.h>
909#include <__algorithm/prev_permutation.h>
910#include <__algorithm/push_heap.h>
911#include <__algorithm/ranges_count.h>
912#include <__algorithm/ranges_count_if.h>
913#include <__algorithm/ranges_find.h>
914#include <__algorithm/ranges_find_if.h>
915#include <__algorithm/ranges_find_if_not.h>
916#include <__algorithm/ranges_max.h>
917#include <__algorithm/ranges_max_element.h>
918#include <__algorithm/ranges_min.h>
919#include <__algorithm/ranges_min_element.h>
920#include <__algorithm/ranges_minmax.h>
921#include <__algorithm/ranges_minmax_element.h>
922#include <__algorithm/ranges_mismatch.h>
923#include <__algorithm/ranges_swap_ranges.h>
924#include <__algorithm/ranges_transform.h>
925#include <__algorithm/remove.h>
926#include <__algorithm/remove_copy.h>
927#include <__algorithm/remove_copy_if.h>
928#include <__algorithm/remove_if.h>
929#include <__algorithm/replace.h>
930#include <__algorithm/replace_copy.h>
931#include <__algorithm/replace_copy_if.h>
932#include <__algorithm/replace_if.h>
933#include <__algorithm/reverse.h>
934#include <__algorithm/reverse_copy.h>
935#include <__algorithm/rotate.h>
936#include <__algorithm/rotate_copy.h>
937#include <__algorithm/sample.h>
938#include <__algorithm/search.h>
939#include <__algorithm/search_n.h>
940#include <__algorithm/set_difference.h>
941#include <__algorithm/set_intersection.h>
942#include <__algorithm/set_symmetric_difference.h>
943#include <__algorithm/set_union.h>
944#include <__algorithm/shift_left.h>
945#include <__algorithm/shift_right.h>
946#include <__algorithm/shuffle.h>
947#include <__algorithm/sift_down.h>
948#include <__algorithm/sort.h>
949#include <__algorithm/sort_heap.h>
950#include <__algorithm/stable_partition.h>
951#include <__algorithm/stable_sort.h>
952#include <__algorithm/swap_ranges.h>
953#include <__algorithm/transform.h>
954#include <__algorithm/unique.h>
955#include <__algorithm/unique_copy.h>
956#include <__algorithm/unwrap_iter.h>
957#include <__algorithm/upper_bound.h>
958
959#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
960#  pragma GCC system_header
961#endif
962
963#if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
964#   include <__pstl_algorithm>
965#endif
966
967#endif // _LIBCPP_ALGORITHM
968