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
23  // [algorithms.results], algorithm result types
24  template <class I, class F>
25    struct in_fun_result;     // since C++20
26
27  template <class I1, class I2>
28    struct in_in_result;      // since C++20
29
30  template <class I, class O>
31    struct in_out_result;  // since C++20
32
33  template <class I1, class I2, class O>
34    struct in_in_out_result;  // since C++20
35
36  template <class I, class O1, class O2>
37    struct in_out_out_result; // since C++20
38
39  template <class I1, class I2>
40    struct min_max_result;    // since C++20
41
42  template <class I>
43    struct in_found_result;   // since C++20
44
45  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
46    indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>             // since C++20
47  constexpr I min_element(I first, S last, Comp comp = {}, Proj proj = {});
48
49  template<forward_range R, class Proj = identity,
50    indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less> // since C++20
51  constexpr borrowed_iterator_t<R> min_element(R&& r, Comp comp = {}, Proj proj = {});
52
53  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
54    indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
55  constexpr I ranges::max_element(I first, S last, Comp comp = {}, Proj proj = {});                        // since C++20
56
57  template<forward_range R, class Proj = identity,
58    indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
59  constexpr borrowed_iterator_t<R> ranges::max_element(R&& r, Comp comp = {}, Proj proj = {});             // since C++20
60
61  template<class I1, class I2>
62    using mismatch_result = in_in_result<I1, I2>;
63
64  template <input_iterator I1, sentinel_for<_I1> S1, input_iterator I2, sentinel_for<_I2> S2,
65          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
66    requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
67  constexpr mismatch_result<_I1, _I2>
68  mismatch()(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {}) // since C++20
69
70  template <input_range R1, input_range R2,
71          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
72    requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
73  constexpr mismatch_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
74  mismatch(R1&& r1, R2&& r2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {})                           // since C++20
75
76    requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
77    constexpr I find(I first, S last, const T& value, Proj proj = {});              // since C++20
78
79  template<input_range R, class T, class Proj = identity>
80    requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
81    constexpr borrowed_iterator_t<R>
82      find(R&& r, const T& value, Proj proj = {});                                  // since C++20
83
84  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
85           indirect_unary_predicate<projected<I, Proj>> Pred>
86    constexpr I find_if(I first, S last, Pred pred, Proj proj = {});                // since C++20
87
88  template<input_range R, class Proj = identity,
89           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
90    constexpr borrowed_iterator_t<R>
91      find_if(R&& r, Pred pred, Proj proj = {});                                    // since C++20
92
93  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
94           indirect_unary_predicate<projected<I, Proj>> Pred>
95    constexpr I find_if_not(I first, S last, Pred pred, Proj proj = {});            // since C++20
96
97  template<input_range R, class Proj = identity,
98           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
99    constexpr borrowed_iterator_t<R>
100      find_if_not(R&& r, Pred pred, Proj proj = {});                                // since C++20
101
102  template<class T, class Proj = identity,
103           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
104    constexpr const T& min(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
105
106  template<copyable T, class Proj = identity,
107           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
108    constexpr T min(initializer_list<T> r, Comp comp = {}, Proj proj = {});         // since C++20
109
110 template<input_range R, class Proj = identity,
111          indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
112   requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
113   constexpr range_value_t<R>
114     min(R&& r, Comp comp = {}, Proj proj = {});                                    // since C++20
115
116  template<class T, class Proj = identity,
117           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
118    constexpr const T& max(const T& a, const T& b, Comp comp = {}, Proj proj = {}); // since C++20
119
120  template<copyable T, class Proj = identity,
121           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
122    constexpr T max(initializer_list<T> r, Comp comp = {}, Proj proj = {});         // since C++20
123
124  template<input_range R, class Proj = identity,
125           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
126    requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
127    constexpr range_value_t<R>
128      max(R&& r, Comp comp = {}, Proj proj = {});                                   // since C++20
129
130  template<class I, class O>
131    using unary_transform_result = in_out_result<I, O>;                             // since C++20
132
133  template<class I1, class I2, class O>
134    using binary_transform_result = in_in_out_result<I1, I2, O>;                    // since C++20
135
136  template<input_iterator I, sentinel_for<I> S, weakly_incrementable O,
137           copy_constructible F, class Proj = identity>
138    requires indirectly_writable<O, indirect_result_t<F&, projected<I, Proj>>>
139    constexpr ranges::unary_transform_result<I, O>
140      transform(I first1, S last1, O result, F op, Proj proj = {});                 // since C++20
141
142  template<input_range R, weakly_incrementable O, copy_constructible F,
143           class Proj = identity>
144    requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R>, Proj>>>
145    constexpr ranges::unary_transform_result<borrowed_iterator_t<R>, O>
146      transform(R&& r, O result, F op, Proj proj = {});                             // since C++20
147
148  template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
149           weakly_incrementable O, copy_constructible F, class Proj1 = identity,
150           class Proj2 = identity>
151    requires indirectly_writable<O, indirect_result_t<F&, projected<I1, Proj1>,
152                                           projected<I2, Proj2>>>
153    constexpr ranges::binary_transform_result<I1, I2, O>
154      transform(I1 first1, S1 last1, I2 first2, S2 last2, O result,
155                        F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {});           // since C++20
156
157  template<input_range R1, input_range R2, weakly_incrementable O,
158           copy_constructible F, class Proj1 = identity, class Proj2 = identity>
159    requires indirectly_writable<O, indirect_result_t<F&, projected<iterator_t<R1>, Proj1>,
160                                           projected<iterator_t<R2>, Proj2>>>
161    constexpr ranges::binary_transform_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
162      transform(R1&& r1, R2&& r2, O result,
163                        F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {});           // since C++20
164
165  template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity>
166    requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
167    constexpr iter_difference_t<I>
168      count(I first, S last, const T& value, Proj proj = {});                       // since C++20
169
170  template<input_range R, class T, class Proj = identity>
171    requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
172    constexpr range_difference_t<R>
173      count(R&& r, const T& value, Proj proj = {});                                 // since C++20
174
175  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
176           indirect_unary_predicate<projected<I, Proj>> Pred>
177    constexpr iter_difference_t<I>
178      count_if(I first, S last, Pred pred, Proj proj = {});                         // since C++20
179
180  template<input_range R, class Proj = identity,
181           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
182    constexpr range_difference_t<R>
183      count_if(R&& r, Pred pred, Proj proj = {});                                   // since C++20
184
185  template<class T>
186  using minmax_result = min_max_result<T>;
187
188  template<class T, class Proj = identity,
189           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
190    constexpr ranges::minmax_result<const T&>
191      minmax(const T& a, const T& b, Comp comp = {}, Proj proj = {});                     // since C++20
192
193  template<copyable T, class Proj = identity,
194           indirect_strict_weak_order<projected<const T*, Proj>> Comp = ranges::less>
195    constexpr ranges::minmax_result<T>
196      minmax(initializer_list<T> r, Comp comp = {}, Proj proj = {});                      // since C++20
197
198  template<input_range R, class Proj = identity,
199           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
200    requires indirectly_copyable_storable<iterator_t<R>, range_value_t<R>*>
201    constexpr ranges::minmax_result<range_value_t<R>>
202      minmax(R&& r, Comp comp = {}, Proj proj = {});                                      // since C++20
203
204  template<class I>
205  using minmax_element_result = min_max_result<I>;
206
207  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
208           indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
209    constexpr ranges::minmax_element_result<I>
210      minmax_element(I first, S last, Comp comp = {}, Proj proj = {});                    // since C++20
211
212  template<forward_range R, class Proj = identity,
213           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
214    constexpr ranges::minmax_element_result<borrowed_iterator_t<R>>
215      minmax_element(R&& r, Comp comp = {}, Proj proj = {});                              // since C++20
216
217  template<class I, class O>
218    using copy_result = in_out_result<I, O>;                                              // since C++20
219
220  template<class I, class O>
221    using copy_n_result = in_out_result<I, O>;                                            // since C++20
222
223  template<class I, class O>
224    using copy_if_result = in_out_result<I, O>;                                             // since C++20
225
226  template<class I1, class I2>
227    using copy_backward_result = in_out_result<I1, I2>;                                     // since C++20
228
229  template<input_iterator I, sentinel_for<I> S, weakly_incrementable O>
230    requires indirectly_copyable<I, O>
231    constexpr ranges::copy_result<I, O> ranges::copy(I first, S last, O result);            // since C++20
232
233  template<input_range R, weakly_incrementable O>
234    requires indirectly_copyable<iterator_t<R>, O>
235    constexpr ranges::copy_result<borrowed_iterator_t<R>, O> ranges::copy(R&& r, O result); // since C++20
236
237  template<input_iterator I, weakly_incrementable O>
238    requires indirectly_copyable<I, O>
239    constexpr ranges::copy_n_result<I, O>
240      ranges::copy_n(I first, iter_difference_t<I> n, O result);                            // since C++20
241
242  template<input_iterator I, sentinel_for<I> S, weakly_incrementable O, class Proj = identity,
243           indirect_unary_predicate<projected<I, Proj>> Pred>
244    requires indirectly_copyable<I, O>
245    constexpr ranges::copy_if_result<I, O>
246      ranges::copy_if(I first, S last, O result, Pred pred, Proj proj = {});                // since C++20
247
248  template<input_range R, weakly_incrementable O, class Proj = identity,
249           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
250    requires indirectly_copyable<iterator_t<R>, O>
251    constexpr ranges::copy_if_result<borrowed_iterator_t<R>, O>
252      ranges::copy_if(R&& r, O result, Pred pred, Proj proj = {});                          // since C++20
253
254  template<bidirectional_iterator I1, sentinel_for<I1> S1, bidirectional_iterator I2>
255    requires indirectly_copyable<I1, I2>
256    constexpr ranges::copy_backward_result<I1, I2>
257      ranges::copy_backward(I1 first, S1 last, I2 result);                                  // since C++20
258
259  template<bidirectional_range R, bidirectional_iterator I>
260    requires indirectly_copyable<iterator_t<R>, I>
261    constexpr ranges::copy_backward_result<borrowed_iterator_t<R>, I>
262      ranges::copy_backward(R&& r, I result);                                               // since C++20
263
264  template<class I, class F>
265    using for_each_result = in_fun_result<I, F>;                                            // since C++20
266
267  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
268           indirectly_unary_invocable<projected<I, Proj>> Fun>
269    constexpr ranges::for_each_result<I, Fun>
270      ranges::for_each(I first, S last, Fun f, Proj proj = {});                             // since C++20
271
272  template<input_range R, class Proj = identity,
273           indirectly_unary_invocable<projected<iterator_t<R>, Proj>> Fun>
274    constexpr ranges::for_each_result<borrowed_iterator_t<R>, Fun>
275      ranges::for_each(R&& r, Fun f, Proj proj = {});                                       // since C++20
276
277  template<input_iterator I, class Proj = identity,
278           indirectly_unary_invocable<projected<I, Proj>> Fun>
279    constexpr ranges::for_each_n_result<I, Fun>
280      ranges::for_each_n(I first, iter_difference_t<I> n, Fun f, Proj proj = {});           // since C++20
281
282  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
283           indirect_unary_predicate<projected<I, Proj>> Pred>
284    constexpr bool ranges::is_partitioned(I first, S last, Pred pred, Proj proj = {});      // since C++20
285
286  template<input_range R, class Proj = identity,
287           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
288    constexpr bool ranges::is_partitioned(R&& r, Pred pred, Proj proj = {});                // since C++20
289
290  template<bidirectional_iterator I, sentinel_for<I> S>
291    requires permutable<I>
292    constexpr I ranges::reverse(I first, S last);                                           // since C++20
293
294  template<bidirectional_range R>
295    requires permutable<iterator_t<R>>
296    constexpr borrowed_iterator_t<R> ranges::reverse(R&& r);                                // since C++20
297
298  template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
299            class Proj = identity>
300    requires sortable<I, Comp, Proj>
301    constexpr I
302      ranges::sort(I first, S last, Comp comp = {}, Proj proj = {});                        // since C++20
303
304  template<random_access_range R, class Comp = ranges::less, class Proj = identity>
305    requires sortable<iterator_t<R>, Comp, Proj>
306    constexpr borrowed_iterator_t<R>
307      ranges::sort(R&& r, Comp comp = {}, Proj proj = {});                                  // since C++20
308
309  template<random_access_iterator I, sentinel_for<I> S, class Comp = ranges::less,
310          class Proj = identity>
311    requires sortable<I, Comp, Proj>
312    I ranges::stable_sort(I first, S last, Comp comp = {}, Proj proj = {});                 // since C++20
313
314  template<random_access_range R, class Comp = ranges::less, class Proj = identity>
315    requires sortable<iterator_t<R>, Comp, Proj>
316    borrowed_iterator_t<R>
317      ranges::stable_sort(R&& r, Comp comp = {}, Proj proj = {});                           // since C++20
318
319  template<class T, output_iterator<const T&> O, sentinel_for<O> S>
320    constexpr O ranges::fill(O first, S last, const T& value);                              // since C++20
321
322  template<class T, output_range<const T&> R>
323    constexpr borrowed_iterator_t<R> ranges::fill(R&& r, const T& value);                   // since C++20
324
325  template<class T, output_iterator<const T&> O>
326    constexpr O ranges::fill_n(O first, iter_difference_t<O> n, const T& value);            // since C++20
327
328 template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
329          class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
330   requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
331   constexpr bool ranges::equal(I1 first1, S1 last1, I2 first2, S2 last2,
332                                Pred pred = {},
333                                Proj1 proj1 = {}, Proj2 proj2 = {});                        // since C++20
334
335 template<input_range R1, input_range R2, class Pred = ranges::equal_to,
336          class Proj1 = identity, class Proj2 = identity>
337   requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
338   constexpr bool ranges::equal(R1&& r1, R2&& r2, Pred pred = {},
339                                Proj1 proj1 = {}, Proj2 proj2 = {});                        // since C++20
340
341  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
342           indirect_unary_predicate<projected<I, Proj>> Pred>
343    constexpr bool ranges::all_of(I first, S last, Pred pred, Proj proj = {});      // since C++20
344
345  template<input_range R, class Proj = identity,
346           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
347    constexpr bool ranges::all_of(R&& r, Pred pred, Proj proj = {});                // since C++20
348
349  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
350           indirect_unary_predicate<projected<I, Proj>> Pred>
351    constexpr bool ranges::any_of(I first, S last, Pred pred, Proj proj = {});      // since C++20
352
353  template<input_range R, class Proj = identity,
354           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
355    constexpr bool ranges::any_of(R&& r, Pred pred, Proj proj = {});                // since C++20
356
357  template<input_iterator I, sentinel_for<I> S, class Proj = identity,
358           indirect_unary_predicate<projected<I, Proj>> Pred>
359    constexpr bool ranges::none_of(I first, S last, Pred pred, Proj proj = {});     // since C++20
360
361  template<input_range R, class Proj = identity,
362           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
363    constexpr bool ranges::none_of(R&& r, Pred pred, Proj proj = {});               // since C++20
364
365  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
366           indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
367    constexpr bool ranges::is_sorted(I first, S last, Comp comp = {}, Proj proj = {});      // since C++20
368
369  template<forward_range R, class Proj = identity,
370           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
371    constexpr bool ranges::is_sorted(R&& r, Comp comp = {}, Proj proj = {});                // since C++20
372
373  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
374           indirect_strict_weak_order<projected<I, Proj>> Comp = ranges::less>
375    constexpr I ranges::is_sorted_until(I first, S last, Comp comp = {}, Proj proj = {});   // since C++20
376
377  template<forward_range R, class Proj = identity,
378           indirect_strict_weak_order<projected<iterator_t<R>, Proj>> Comp = ranges::less>
379    constexpr borrowed_iterator_t<R>
380      ranges::is_sorted_until(R&& r, Comp comp = {}, Proj proj = {});                       // since C++20
381
382  template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
383           indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less>
384    constexpr I upper_bound(I first, S last, const T& value, Comp comp = {}, Proj proj = {}); // since C++20
385
386  template<forward_range R, class T, class Proj = identity,
387           indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
388             ranges::less>
389    constexpr borrowed_iterator_t<R>
390      upper_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {});                     // since C++20
391
392  template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
393           indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less>
394    constexpr I lower_bound(I first, S last, const T& value, Comp comp = {},
395                                    Proj proj = {});                                          // since C++20
396  template<forward_range R, class T, class Proj = identity,
397           indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
398             ranges::less>
399    constexpr borrowed_iterator_t<R>
400      lower_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {});                     // since C++20
401
402  template<forward_iterator I, sentinel_for<I> S, class T, class Proj = identity,
403           indirect_strict_weak_order<const T*, projected<I, Proj>> Comp = ranges::less>
404    constexpr bool binary_search(I first, S last, const T& value, Comp comp = {},
405                                         Proj proj = {});                                     // since C++20
406
407  template<forward_range R, class T, class Proj = identity,
408           indirect_strict_weak_order<const T*, projected<iterator_t<R>, Proj>> Comp =
409             ranges::less>
410    constexpr bool binary_search(R&& r, const T& value, Comp comp = {},
411                                         Proj proj = {});                                     // since C++20
412  template<input_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2,
413           class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
414    requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
415    constexpr I1 ranges::find_first_of(I1 first1, S1 last1, I2 first2, S2 last2,
416                                       Pred pred = {},
417                                       Proj1 proj1 = {}, Proj2 proj2 = {});                 // since C++20
418
419  template<input_range R1, forward_range R2,
420           class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
421    requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
422    constexpr borrowed_iterator_t<R1>
423      ranges::find_first_of(R1&& r1, R2&& r2,
424                            Pred pred = {},
425                            Proj1 proj1 = {}, Proj2 proj2 = {});                            // since C++20
426
427  template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
428           indirect_binary_predicate<projected<I, Proj>,
429                                     projected<I, Proj>> Pred = ranges::equal_to>
430    constexpr I ranges::adjacent_find(I first, S last, Pred pred = {}, Proj proj = {});     // since C+20
431
432  template<forward_range R, class Proj = identity,
433           indirect_binary_predicate<projected<iterator_t<R>, Proj>,
434                                     projected<iterator_t<R>, Proj>> Pred = ranges::equal_to>
435    constexpr borrowed_iterator_t<R> ranges::adjacent_find(R&& r, Pred pred = {}, Proj proj = {});  // since C++20
436
437  template<input_iterator I, sentinel_for<I> S, class T1, class T2, class Proj = identity>
438    requires indirectly_writable<I, const T2&> &&
439             indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T1*>
440    constexpr I
441      ranges::replace(I first, S last, const T1& old_value, const T2& new_value, Proj proj = {});   // since C++20
442
443  template<input_range R, class T1, class T2, class Proj = identity>
444    requires indirectly_writable<iterator_t<R>, const T2&> &&
445             indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T1*>
446    constexpr borrowed_iterator_t<R>
447      ranges::replace(R&& r, const T1& old_value, const T2& new_value, Proj proj = {});             // since C++20
448
449  template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity,
450           indirect_unary_predicate<projected<I, Proj>> Pred>
451    requires indirectly_writable<I, const T&>
452    constexpr I ranges::replace_if(I first, S last, Pred pred, const T& new_value, Proj proj = {}); // since C++20
453
454  template<input_range R, class T, class Proj = identity,
455           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
456    requires indirectly_writable<iterator_t<R>, const T&>
457    constexpr borrowed_iterator_t<R>
458      ranges::replace_if(R&& r, Pred pred, const T& new_value, Proj proj = {});                     // since C++20
459
460  template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
461           class Proj1 = identity, class Proj2 = identity,
462           indirect_strict_weak_order<projected<I1, Proj1>,
463                                      projected<I2, Proj2>> Comp = ranges::less>
464    constexpr bool
465      ranges::lexicographical_compare(I1 first1, S1 last1, I2 first2, S2 last2,
466                                      Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});    // since C++20
467
468  template<input_range R1, input_range R2, class Proj1 = identity,
469           class Proj2 = identity,
470           indirect_strict_weak_order<projected<iterator_t<R1>, Proj1>,
471                                      projected<iterator_t<R2>, Proj2>> Comp = ranges::less>
472    constexpr bool
473      ranges::lexicographical_compare(R1&& r1, R2&& r2, Comp comp = {},
474                                      Proj1 proj1 = {}, Proj2 proj2 = {});                    // since C++20
475
476  template<bidirectional_iterator I1, sentinel_for<I1> S1, bidirectional_iterator I2>
477    requires indirectly_movable<I1, I2>
478    constexpr ranges::move_backward_result<I1, I2>
479      ranges::move_backward(I1 first, S1 last, I2 result);                                          // since C++20
480
481  template<bidirectional_range R, bidirectional_iterator I>
482    requires indirectly_movable<iterator_t<R>, I>
483    constexpr ranges::move_backward_result<borrowed_iterator_t<R>, I>
484      ranges::move_backward(R&& r, I result);                                                       // since C++20
485
486  template<input_iterator I, sentinel_for<I> S, weakly_incrementable O>
487    requires indirectly_movable<I, O>
488    constexpr ranges::move_result<I, O>
489      ranges::move(I first, S last, O result);                                                      // since C++20
490
491  template<input_range R, weakly_incrementable O>
492    requires indirectly_movable<iterator_t<R>, O>
493    constexpr ranges::move_result<borrowed_iterator_t<R>, O>
494      ranges::move(R&& r, O result);                                                                // since C++20
495
496  template<class I1, class I2, class O>
497    using merge_result = in_in_out_result<I1, I2, O>;                                               // since C++20
498
499  template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
500           weakly_incrementable O, class Comp = ranges::less, class Proj1 = identity,
501           class Proj2 = identity>
502    requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
503    constexpr merge_result<I1, I2, O>
504      merge(I1 first1, S1 last1, I2 first2, S2 last2, O result,
505            Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});                                    // since C++20
506
507  template<input_range R1, input_range R2, weakly_incrementable O, class Comp = ranges::less,
508           class Proj1 = identity, class Proj2 = identity>
509    requires mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
510    constexpr merge_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>, O>
511      merge(R1&& r1, R2&& r2, O result,
512            Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});                                    // since C++20
513
514  template<permutable I, sentinel_for<I> S, class T, class Proj = identity>
515    requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
516    constexpr subrange<I> ranges::remove(I first, S last, const T& value, Proj proj = {});          // since C++20
517
518  template<forward_range R, class T, class Proj = identity>
519    requires permutable<iterator_t<R>> &&
520             indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
521    constexpr borrowed_subrange_t<R>
522      ranges::remove(R&& r, const T& value, Proj proj = {});                                        // since C++20
523
524  template<permutable I, sentinel_for<I> S, class Proj = identity,
525           indirect_unary_predicate<projected<I, Proj>> Pred>
526    constexpr subrange<I> ranges::remove_if(I first, S last, Pred pred, Proj proj = {});            // since C++20
527
528  template<forward_range R, class Proj = identity,
529           indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
530    requires permutable<iterator_t<R>>
531    constexpr borrowed_subrange_t<R>
532      ranges::remove_if(R&& r, Pred pred, Proj proj = {});                                          // since C++20
533
534  template<class I, class O>
535    using set_difference_result = in_out_result<I, O>;                                              // since C++20
536
537  template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
538           weakly_incrementable O, class Comp = ranges::less,
539           class Proj1 = identity, class Proj2 = identity>
540    requires mergeable<I1, I2, O, Comp, Proj1, Proj2>
541    constexpr set_difference_result<I1, O>
542      set_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
543                     Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});                           // since C++20
544
545  template<input_range R1, input_range R2, weakly_incrementable O,
546           class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
547    requires mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
548    constexpr set_difference_result<borrowed_iterator_t<R1>, O>
549      set_difference(R1&& r1, R2&& r2, O result,
550                     Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});                           // since C++20
551
552}
553
554    constexpr bool     // constexpr in C++20
555    all_of(InputIterator first, InputIterator last, Predicate pred);
556
557template <class InputIterator, class Predicate>
558    constexpr bool     // constexpr in C++20
559    any_of(InputIterator first, InputIterator last, Predicate pred);
560
561template <class InputIterator, class Predicate>
562    constexpr bool     // constexpr in C++20
563    none_of(InputIterator first, InputIterator last, Predicate pred);
564
565template <class InputIterator, class Function>
566    constexpr Function          // constexpr in C++20
567    for_each(InputIterator first, InputIterator last, Function f);
568
569template<class InputIterator, class Size, class Function>
570    constexpr InputIterator     // constexpr in C++20
571    for_each_n(InputIterator first, Size n, Function f); // C++17
572
573template <class InputIterator, class T>
574    constexpr InputIterator     // constexpr in C++20
575    find(InputIterator first, InputIterator last, const T& value);
576
577template <class InputIterator, class Predicate>
578    constexpr InputIterator     // constexpr in C++20
579    find_if(InputIterator first, InputIterator last, Predicate pred);
580
581template<class InputIterator, class Predicate>
582    constexpr InputIterator     // constexpr in C++20
583    find_if_not(InputIterator first, InputIterator last, Predicate pred);
584
585template <class ForwardIterator1, class ForwardIterator2>
586    constexpr ForwardIterator1  // constexpr in C++20
587    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
588             ForwardIterator2 first2, ForwardIterator2 last2);
589
590template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
591    constexpr ForwardIterator1  // constexpr in C++20
592    find_end(ForwardIterator1 first1, ForwardIterator1 last1,
593             ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
594
595template <class ForwardIterator1, class ForwardIterator2>
596    constexpr ForwardIterator1  // constexpr in C++20
597    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
598                  ForwardIterator2 first2, ForwardIterator2 last2);
599
600template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
601    constexpr ForwardIterator1  // constexpr in C++20
602    find_first_of(ForwardIterator1 first1, ForwardIterator1 last1,
603                  ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
604
605template <class ForwardIterator>
606    constexpr ForwardIterator   // constexpr in C++20
607    adjacent_find(ForwardIterator first, ForwardIterator last);
608
609template <class ForwardIterator, class BinaryPredicate>
610    constexpr ForwardIterator   // constexpr in C++20
611    adjacent_find(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
612
613template <class InputIterator, class T>
614    constexpr typename iterator_traits<InputIterator>::difference_type  // constexpr in C++20
615    count(InputIterator first, InputIterator last, const T& value);
616
617template <class InputIterator, class Predicate>
618    constexpr typename iterator_traits<InputIterator>::difference_type // constexpr in C++20
619    count_if(InputIterator first, InputIterator last, Predicate pred);
620
621template <class InputIterator1, class InputIterator2>
622    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
623    mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
624
625template <class InputIterator1, class InputIterator2>
626    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
627    mismatch(InputIterator1 first1, InputIterator1 last1,
628             InputIterator2 first2, InputIterator2 last2); // **C++14**
629
630template <class InputIterator1, class InputIterator2, class BinaryPredicate>
631    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
632    mismatch(InputIterator1 first1, InputIterator1 last1,
633             InputIterator2 first2, BinaryPredicate pred);
634
635template <class InputIterator1, class InputIterator2, class BinaryPredicate>
636    constexpr pair<InputIterator1, InputIterator2>   // constexpr in C++20
637    mismatch(InputIterator1 first1, InputIterator1 last1,
638             InputIterator2 first2, InputIterator2 last2,
639             BinaryPredicate pred); // **C++14**
640
641template <class InputIterator1, class InputIterator2>
642    constexpr bool      // constexpr in C++20
643    equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
644
645template <class InputIterator1, class InputIterator2>
646    constexpr bool      // constexpr in C++20
647    equal(InputIterator1 first1, InputIterator1 last1,
648          InputIterator2 first2, InputIterator2 last2); // **C++14**
649
650template <class InputIterator1, class InputIterator2, class BinaryPredicate>
651    constexpr bool      // constexpr in C++20
652    equal(InputIterator1 first1, InputIterator1 last1,
653          InputIterator2 first2, BinaryPredicate pred);
654
655template <class InputIterator1, class InputIterator2, class BinaryPredicate>
656    constexpr bool      // constexpr in C++20
657    equal(InputIterator1 first1, InputIterator1 last1,
658          InputIterator2 first2, InputIterator2 last2,
659          BinaryPredicate pred); // **C++14**
660
661template<class ForwardIterator1, class ForwardIterator2>
662    constexpr bool      // constexpr in C++20
663    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
664                   ForwardIterator2 first2);
665
666template<class ForwardIterator1, class ForwardIterator2>
667    constexpr bool      // constexpr in C++20
668    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
669                   ForwardIterator2 first2, ForwardIterator2 last2); // **C++14**
670
671template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
672    constexpr bool      // constexpr in C++20
673    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
674                   ForwardIterator2 first2, BinaryPredicate pred);
675
676template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
677    constexpr bool      // constexpr in C++20
678    is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
679                   ForwardIterator2 first2, ForwardIterator2 last2,
680                   BinaryPredicate pred);  // **C++14**
681
682template <class ForwardIterator1, class ForwardIterator2>
683    constexpr ForwardIterator1      // constexpr in C++20
684    search(ForwardIterator1 first1, ForwardIterator1 last1,
685           ForwardIterator2 first2, ForwardIterator2 last2);
686
687template <class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
688    constexpr ForwardIterator1      // constexpr in C++20
689    search(ForwardIterator1 first1, ForwardIterator1 last1,
690           ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
691
692template <class ForwardIterator, class Size, class T>
693    constexpr ForwardIterator       // constexpr in C++20
694    search_n(ForwardIterator first, ForwardIterator last, Size count, const T& value);
695
696template <class ForwardIterator, class Size, class T, class BinaryPredicate>
697    constexpr ForwardIterator       // constexpr in C++20
698    search_n(ForwardIterator first, ForwardIterator last,
699             Size count, const T& value, BinaryPredicate pred);
700
701template <class InputIterator, class OutputIterator>
702    constexpr OutputIterator      // constexpr in C++20
703    copy(InputIterator first, InputIterator last, OutputIterator result);
704
705template<class InputIterator, class OutputIterator, class Predicate>
706    constexpr OutputIterator      // constexpr in C++20
707    copy_if(InputIterator first, InputIterator last,
708            OutputIterator result, Predicate pred);
709
710template<class InputIterator, class Size, class OutputIterator>
711    constexpr OutputIterator      // constexpr in C++20
712    copy_n(InputIterator first, Size n, OutputIterator result);
713
714template <class BidirectionalIterator1, class BidirectionalIterator2>
715    constexpr BidirectionalIterator2      // constexpr in C++20
716    copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
717                  BidirectionalIterator2 result);
718
719// [alg.move], move
720template<class InputIterator, class OutputIterator>
721    constexpr OutputIterator move(InputIterator first, InputIterator last,
722                                OutputIterator result);
723
724template<class BidirectionalIterator1, class BidirectionalIterator2>
725    constexpr BidirectionalIterator2
726    move_backward(BidirectionalIterator1 first, BidirectionalIterator1 last,
727                  BidirectionalIterator2 result);
728
729template <class ForwardIterator1, class ForwardIterator2>
730    constexpr ForwardIterator2    // constexpr in C++20
731    swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);
732
733namespace ranges {
734    template<class I1, class I2>
735    using swap_ranges_result = in_in_result<I1, I2>;
736
737template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2>
738        requires indirectly_swappable<I1, I2>
739    constexpr ranges::swap_ranges_result<I1, I2>
740        swap_ranges(I1 first1, S1 last1, I2 first2, S2 last2);
741
742template<input_range R1, input_range R2>
743        requires indirectly_swappable<iterator_t<R1>, iterator_t<R2>>
744    constexpr ranges::swap_ranges_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
745        swap_ranges(R1&& r1, R2&& r2);
746}
747
748template <class ForwardIterator1, class ForwardIterator2>
749    constexpr void                // constexpr in C++20
750    iter_swap(ForwardIterator1 a, ForwardIterator2 b);
751
752template <class InputIterator, class OutputIterator, class UnaryOperation>
753    constexpr OutputIterator      // constexpr in C++20
754    transform(InputIterator first, InputIterator last, OutputIterator result, UnaryOperation op);
755
756template <class InputIterator1, class InputIterator2, class OutputIterator, class BinaryOperation>
757    constexpr OutputIterator      // constexpr in C++20
758    transform(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2,
759              OutputIterator result, BinaryOperation binary_op);
760
761template <class ForwardIterator, class T>
762    constexpr void      // constexpr in C++20
763    replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value);
764
765template <class ForwardIterator, class Predicate, class T>
766    constexpr void      // constexpr in C++20
767    replace_if(ForwardIterator first, ForwardIterator last, Predicate pred, const T& new_value);
768
769template <class InputIterator, class OutputIterator, class T>
770    constexpr OutputIterator      // constexpr in C++20
771    replace_copy(InputIterator first, InputIterator last, OutputIterator result,
772                 const T& old_value, const T& new_value);
773
774template <class InputIterator, class OutputIterator, class Predicate, class T>
775    constexpr OutputIterator      // constexpr in C++20
776    replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value);
777
778template <class ForwardIterator, class T>
779    constexpr void      // constexpr in C++20
780    fill(ForwardIterator first, ForwardIterator last, const T& value);
781
782template <class OutputIterator, class Size, class T>
783    constexpr OutputIterator      // constexpr in C++20
784    fill_n(OutputIterator first, Size n, const T& value);
785
786template <class ForwardIterator, class Generator>
787    constexpr void      // constexpr in C++20
788    generate(ForwardIterator first, ForwardIterator last, Generator gen);
789
790template <class OutputIterator, class Size, class Generator>
791    constexpr OutputIterator      // constexpr in C++20
792    generate_n(OutputIterator first, Size n, Generator gen);
793
794template <class ForwardIterator, class T>
795    constexpr ForwardIterator     // constexpr in C++20
796    remove(ForwardIterator first, ForwardIterator last, const T& value);
797
798template <class ForwardIterator, class Predicate>
799    constexpr ForwardIterator     // constexpr in C++20
800    remove_if(ForwardIterator first, ForwardIterator last, Predicate pred);
801
802template <class InputIterator, class OutputIterator, class T>
803    constexpr OutputIterator     // constexpr in C++20
804    remove_copy(InputIterator first, InputIterator last, OutputIterator result, const T& value);
805
806template <class InputIterator, class OutputIterator, class Predicate>
807    constexpr OutputIterator     // constexpr in C++20
808    remove_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred);
809
810template <class ForwardIterator>
811    constexpr ForwardIterator    // constexpr in C++20
812    unique(ForwardIterator first, ForwardIterator last);
813
814template <class ForwardIterator, class BinaryPredicate>
815    constexpr ForwardIterator    // constexpr in C++20
816    unique(ForwardIterator first, ForwardIterator last, BinaryPredicate pred);
817
818template <class InputIterator, class OutputIterator>
819    constexpr OutputIterator     // constexpr in C++20
820    unique_copy(InputIterator first, InputIterator last, OutputIterator result);
821
822template <class InputIterator, class OutputIterator, class BinaryPredicate>
823    constexpr OutputIterator     // constexpr in C++20
824    unique_copy(InputIterator first, InputIterator last, OutputIterator result, BinaryPredicate pred);
825
826template <class BidirectionalIterator>
827    constexpr void               // constexpr in C++20
828    reverse(BidirectionalIterator first, BidirectionalIterator last);
829
830template <class BidirectionalIterator, class OutputIterator>
831    constexpr OutputIterator       // constexpr in C++20
832    reverse_copy(BidirectionalIterator first, BidirectionalIterator last, OutputIterator result);
833
834template <class ForwardIterator>
835    constexpr ForwardIterator      // constexpr in C++20
836    rotate(ForwardIterator first, ForwardIterator middle, ForwardIterator last);
837
838template <class ForwardIterator, class OutputIterator>
839    constexpr OutputIterator       // constexpr in C++20
840    rotate_copy(ForwardIterator first, ForwardIterator middle, ForwardIterator last, OutputIterator result);
841
842template <class RandomAccessIterator>
843    void
844    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
845
846template <class RandomAccessIterator, class RandomNumberGenerator>
847    void
848    random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
849                   RandomNumberGenerator& rand);  // deprecated in C++14, removed in C++17
850
851template<class PopulationIterator, class SampleIterator,
852         class Distance, class UniformRandomBitGenerator>
853    SampleIterator sample(PopulationIterator first, PopulationIterator last,
854                          SampleIterator out, Distance n,
855                          UniformRandomBitGenerator&& g); // C++17
856
857template<class RandomAccessIterator, class UniformRandomNumberGenerator>
858    void shuffle(RandomAccessIterator first, RandomAccessIterator last,
859                 UniformRandomNumberGenerator&& g);
860
861template<class ForwardIterator>
862  constexpr ForwardIterator
863    shift_left(ForwardIterator first, ForwardIterator last,
864               typename iterator_traits<ForwardIterator>::difference_type n); // C++20
865
866template<class ForwardIterator>
867  constexpr ForwardIterator
868    shift_right(ForwardIterator first, ForwardIterator last,
869                typename iterator_traits<ForwardIterator>::difference_type n); // C++20
870
871template <class InputIterator, class Predicate>
872    constexpr bool  // constexpr in C++20
873    is_partitioned(InputIterator first, InputIterator last, Predicate pred);
874
875template <class ForwardIterator, class Predicate>
876    constexpr ForwardIterator  // constexpr in C++20
877    partition(ForwardIterator first, ForwardIterator last, Predicate pred);
878
879template <class InputIterator, class OutputIterator1,
880          class OutputIterator2, class Predicate>
881    constexpr pair<OutputIterator1, OutputIterator2>   // constexpr in C++20
882    partition_copy(InputIterator first, InputIterator last,
883                   OutputIterator1 out_true, OutputIterator2 out_false,
884                   Predicate pred);
885
886template <class ForwardIterator, class Predicate>
887    ForwardIterator
888    stable_partition(ForwardIterator first, ForwardIterator last, Predicate pred);
889
890template<class ForwardIterator, class Predicate>
891    constexpr ForwardIterator  // constexpr in C++20
892    partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
893
894template <class ForwardIterator>
895    constexpr bool  // constexpr in C++20
896    is_sorted(ForwardIterator first, ForwardIterator last);
897
898template <class ForwardIterator, class Compare>
899    constexpr bool  // constexpr in C++20
900    is_sorted(ForwardIterator first, ForwardIterator last, Compare comp);
901
902template<class ForwardIterator>
903    constexpr ForwardIterator    // constexpr in C++20
904    is_sorted_until(ForwardIterator first, ForwardIterator last);
905
906template <class ForwardIterator, class Compare>
907    constexpr ForwardIterator    // constexpr in C++20
908    is_sorted_until(ForwardIterator first, ForwardIterator last, Compare comp);
909
910template <class RandomAccessIterator>
911    constexpr void               // constexpr in C++20
912    sort(RandomAccessIterator first, RandomAccessIterator last);
913
914template <class RandomAccessIterator, class Compare>
915    constexpr void               // constexpr in C++20
916    sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
917
918template <class RandomAccessIterator>
919    void
920    stable_sort(RandomAccessIterator first, RandomAccessIterator last);
921
922template <class RandomAccessIterator, class Compare>
923    void
924    stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
925
926template <class RandomAccessIterator>
927    constexpr void                    // constexpr in C++20
928    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last);
929
930template <class RandomAccessIterator, class Compare>
931    constexpr void                    // constexpr in C++20
932    partial_sort(RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);
933
934template <class InputIterator, class RandomAccessIterator>
935    constexpr RandomAccessIterator    // constexpr in C++20
936    partial_sort_copy(InputIterator first, InputIterator last,
937                      RandomAccessIterator result_first, RandomAccessIterator result_last);
938
939template <class InputIterator, class RandomAccessIterator, class Compare>
940    constexpr RandomAccessIterator    // constexpr in C++20
941    partial_sort_copy(InputIterator first, InputIterator last,
942                      RandomAccessIterator result_first, RandomAccessIterator result_last, Compare comp);
943
944template <class RandomAccessIterator>
945    constexpr void                    // constexpr in C++20
946    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last);
947
948template <class RandomAccessIterator, class Compare>
949    constexpr void                    // constexpr in C++20
950    nth_element(RandomAccessIterator first, RandomAccessIterator nth, RandomAccessIterator last, Compare comp);
951
952template <class ForwardIterator, class T>
953    constexpr ForwardIterator                         // constexpr in C++20
954    lower_bound(ForwardIterator first, ForwardIterator last, const T& value);
955
956template <class ForwardIterator, class T, class Compare>
957    constexpr ForwardIterator                         // constexpr in C++20
958    lower_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
959
960template <class ForwardIterator, class T>
961    constexpr ForwardIterator                         // constexpr in C++20
962    upper_bound(ForwardIterator first, ForwardIterator last, const T& value);
963
964template <class ForwardIterator, class T, class Compare>
965    constexpr ForwardIterator                         // constexpr in C++20
966    upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
967
968template <class ForwardIterator, class T>
969    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
970    equal_range(ForwardIterator first, ForwardIterator last, const T& value);
971
972template <class ForwardIterator, class T, class Compare>
973    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++20
974    equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
975
976template <class ForwardIterator, class T>
977    constexpr bool                                    // constexpr in C++20
978    binary_search(ForwardIterator first, ForwardIterator last, const T& value);
979
980template <class ForwardIterator, class T, class Compare>
981    constexpr bool                                    // constexpr in C++20
982    binary_search(ForwardIterator first, ForwardIterator last, const T& value, Compare comp);
983
984template <class InputIterator1, class InputIterator2, class OutputIterator>
985    constexpr OutputIterator                          // constexpr in C++20
986    merge(InputIterator1 first1, InputIterator1 last1,
987          InputIterator2 first2, InputIterator2 last2, OutputIterator result);
988
989template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
990    constexpr OutputIterator                          // constexpr in C++20
991    merge(InputIterator1 first1, InputIterator1 last1,
992          InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
993
994template <class BidirectionalIterator>
995    void
996    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
997
998template <class BidirectionalIterator, class Compare>
999    void
1000    inplace_merge(BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);
1001
1002template <class InputIterator1, class InputIterator2>
1003    constexpr bool                                    // constexpr in C++20
1004    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
1005
1006template <class InputIterator1, class InputIterator2, class Compare>
1007    constexpr bool                                    // constexpr in C++20
1008    includes(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, Compare comp);
1009
1010template <class InputIterator1, class InputIterator2, class OutputIterator>
1011    constexpr OutputIterator                          // constexpr in C++20
1012    set_union(InputIterator1 first1, InputIterator1 last1,
1013              InputIterator2 first2, InputIterator2 last2, OutputIterator result);
1014
1015template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
1016    constexpr OutputIterator                          // constexpr in C++20
1017    set_union(InputIterator1 first1, InputIterator1 last1,
1018              InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
1019
1020template <class InputIterator1, class InputIterator2, class OutputIterator>
1021    constexpr OutputIterator                         // constexpr in C++20
1022    set_intersection(InputIterator1 first1, InputIterator1 last1,
1023                     InputIterator2 first2, InputIterator2 last2, OutputIterator result);
1024
1025template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
1026    constexpr OutputIterator                         // constexpr in C++20
1027    set_intersection(InputIterator1 first1, InputIterator1 last1,
1028                     InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
1029
1030template <class InputIterator1, class InputIterator2, class OutputIterator>
1031    constexpr OutputIterator                         // constexpr in C++20
1032    set_difference(InputIterator1 first1, InputIterator1 last1,
1033                   InputIterator2 first2, InputIterator2 last2, OutputIterator result);
1034
1035template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
1036    constexpr OutputIterator                         // constexpr in C++20
1037    set_difference(InputIterator1 first1, InputIterator1 last1,
1038                   InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
1039
1040template <class InputIterator1, class InputIterator2, class OutputIterator>
1041    constexpr OutputIterator                         // constexpr in C++20
1042    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
1043                             InputIterator2 first2, InputIterator2 last2, OutputIterator result);
1044
1045template <class InputIterator1, class InputIterator2, class OutputIterator, class Compare>
1046    constexpr OutputIterator                         // constexpr in C++20
1047    set_symmetric_difference(InputIterator1 first1, InputIterator1 last1,
1048                             InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp);
1049
1050template <class RandomAccessIterator>
1051    constexpr void                                   // constexpr in C++20
1052    push_heap(RandomAccessIterator first, RandomAccessIterator last);
1053
1054template <class RandomAccessIterator, class Compare>
1055    constexpr void                                   // constexpr in C++20
1056    push_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
1057
1058template <class RandomAccessIterator>
1059    constexpr void                                   // constexpr in C++20
1060    pop_heap(RandomAccessIterator first, RandomAccessIterator last);
1061
1062template <class RandomAccessIterator, class Compare>
1063    constexpr void                                   // constexpr in C++20
1064    pop_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
1065
1066template <class RandomAccessIterator>
1067    constexpr void                                   // constexpr in C++20
1068    make_heap(RandomAccessIterator first, RandomAccessIterator last);
1069
1070template <class RandomAccessIterator, class Compare>
1071    constexpr void                                   // constexpr in C++20
1072    make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
1073
1074template <class RandomAccessIterator>
1075    constexpr void                                   // constexpr in C++20
1076    sort_heap(RandomAccessIterator first, RandomAccessIterator last);
1077
1078template <class RandomAccessIterator, class Compare>
1079    constexpr void                                   // constexpr in C++20
1080    sort_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp);
1081
1082template <class RandomAccessIterator>
1083    constexpr bool   // constexpr in C++20
1084    is_heap(RandomAccessIterator first, RandomAccessiterator last);
1085
1086template <class RandomAccessIterator, class Compare>
1087    constexpr bool   // constexpr in C++20
1088    is_heap(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
1089
1090template <class RandomAccessIterator>
1091    constexpr RandomAccessIterator   // constexpr in C++20
1092    is_heap_until(RandomAccessIterator first, RandomAccessiterator last);
1093
1094template <class RandomAccessIterator, class Compare>
1095    constexpr RandomAccessIterator   // constexpr in C++20
1096    is_heap_until(RandomAccessIterator first, RandomAccessiterator last, Compare comp);
1097
1098template <class ForwardIterator>
1099    constexpr ForwardIterator        // constexpr in C++14
1100    min_element(ForwardIterator first, ForwardIterator last);
1101
1102template <class ForwardIterator, class Compare>
1103    constexpr ForwardIterator        // constexpr in C++14
1104    min_element(ForwardIterator first, ForwardIterator last, Compare comp);
1105
1106template <class T>
1107    constexpr const T&               // constexpr in C++14
1108    min(const T& a, const T& b);
1109
1110template <class T, class Compare>
1111    constexpr const T&               // constexpr in C++14
1112    min(const T& a, const T& b, Compare comp);
1113
1114template<class T>
1115    constexpr T                      // constexpr in C++14
1116    min(initializer_list<T> t);
1117
1118template<class T, class Compare>
1119    constexpr T                      // constexpr in C++14
1120    min(initializer_list<T> t, Compare comp);
1121
1122template<class T>
1123    constexpr const T& clamp(const T& v, const T& lo, const T& hi);               // C++17
1124
1125template<class T, class Compare>
1126    constexpr const T& clamp(const T& v, const T& lo, const T& hi, Compare comp); // C++17
1127
1128template <class ForwardIterator>
1129    constexpr ForwardIterator        // constexpr in C++14
1130    max_element(ForwardIterator first, ForwardIterator last);
1131
1132template <class ForwardIterator, class Compare>
1133    constexpr ForwardIterator        // constexpr in C++14
1134    max_element(ForwardIterator first, ForwardIterator last, Compare comp);
1135
1136template <class T>
1137    constexpr const T&               // constexpr in C++14
1138    max(const T& a, const T& b);
1139
1140template <class T, class Compare>
1141    constexpr const T&               // constexpr in C++14
1142    max(const T& a, const T& b, Compare comp);
1143
1144template<class T>
1145    constexpr T                      // constexpr in C++14
1146    max(initializer_list<T> t);
1147
1148template<class T, class Compare>
1149    constexpr T                      // constexpr in C++14
1150    max(initializer_list<T> t, Compare comp);
1151
1152template<class ForwardIterator>
1153    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++14
1154    minmax_element(ForwardIterator first, ForwardIterator last);
1155
1156template<class ForwardIterator, class Compare>
1157    constexpr pair<ForwardIterator, ForwardIterator>  // constexpr in C++14
1158    minmax_element(ForwardIterator first, ForwardIterator last, Compare comp);
1159
1160template<class T>
1161    constexpr pair<const T&, const T&>  // constexpr in C++14
1162    minmax(const T& a, const T& b);
1163
1164template<class T, class Compare>
1165    constexpr pair<const T&, const T&>  // constexpr in C++14
1166    minmax(const T& a, const T& b, Compare comp);
1167
1168template<class T>
1169    constexpr pair<T, T>                // constexpr in C++14
1170    minmax(initializer_list<T> t);
1171
1172template<class T, class Compare>
1173    constexpr pair<T, T>                // constexpr in C++14
1174    minmax(initializer_list<T> t, Compare comp);
1175
1176template <class InputIterator1, class InputIterator2>
1177    constexpr bool     // constexpr in C++20
1178    lexicographical_compare(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2);
1179
1180template <class InputIterator1, class InputIterator2, class Compare>
1181    constexpr bool     // constexpr in C++20
1182    lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
1183                            InputIterator2 first2, InputIterator2 last2, Compare comp);
1184
1185template <class BidirectionalIterator>
1186    constexpr bool     // constexpr in C++20
1187    next_permutation(BidirectionalIterator first, BidirectionalIterator last);
1188
1189template <class BidirectionalIterator, class Compare>
1190    constexpr bool     // constexpr in C++20
1191    next_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
1192
1193template <class BidirectionalIterator>
1194    constexpr bool     // constexpr in C++20
1195    prev_permutation(BidirectionalIterator first, BidirectionalIterator last);
1196
1197template <class BidirectionalIterator, class Compare>
1198    constexpr bool     // constexpr in C++20
1199    prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
1200}  // std
1201
1202*/
1203
1204#include <__assert> // all public C++ headers provide the assertion handler
1205#include <__bits>
1206#include <__config>
1207#include <__debug>
1208#include <cstddef>
1209#include <cstring>
1210#include <memory>
1211#include <type_traits>
1212#include <version>
1213
1214#include <__algorithm/adjacent_find.h>
1215#include <__algorithm/all_of.h>
1216#include <__algorithm/any_of.h>
1217#include <__algorithm/binary_search.h>
1218#include <__algorithm/clamp.h>
1219#include <__algorithm/comp.h>
1220#include <__algorithm/comp_ref_type.h>
1221#include <__algorithm/copy.h>
1222#include <__algorithm/copy_backward.h>
1223#include <__algorithm/copy_if.h>
1224#include <__algorithm/copy_n.h>
1225#include <__algorithm/count.h>
1226#include <__algorithm/count_if.h>
1227#include <__algorithm/equal.h>
1228#include <__algorithm/equal_range.h>
1229#include <__algorithm/fill.h>
1230#include <__algorithm/fill_n.h>
1231#include <__algorithm/find.h>
1232#include <__algorithm/find_end.h>
1233#include <__algorithm/find_first_of.h>
1234#include <__algorithm/find_if.h>
1235#include <__algorithm/find_if_not.h>
1236#include <__algorithm/for_each.h>
1237#include <__algorithm/for_each_n.h>
1238#include <__algorithm/generate.h>
1239#include <__algorithm/generate_n.h>
1240#include <__algorithm/half_positive.h>
1241#include <__algorithm/in_found_result.h>
1242#include <__algorithm/in_fun_result.h>
1243#include <__algorithm/in_in_out_result.h>
1244#include <__algorithm/in_in_result.h>
1245#include <__algorithm/in_out_out_result.h>
1246#include <__algorithm/in_out_result.h>
1247#include <__algorithm/includes.h>
1248#include <__algorithm/inplace_merge.h>
1249#include <__algorithm/is_heap.h>
1250#include <__algorithm/is_heap_until.h>
1251#include <__algorithm/is_partitioned.h>
1252#include <__algorithm/is_permutation.h>
1253#include <__algorithm/is_sorted.h>
1254#include <__algorithm/is_sorted_until.h>
1255#include <__algorithm/iter_swap.h>
1256#include <__algorithm/lexicographical_compare.h>
1257#include <__algorithm/lower_bound.h>
1258#include <__algorithm/make_heap.h>
1259#include <__algorithm/max.h>
1260#include <__algorithm/max_element.h>
1261#include <__algorithm/merge.h>
1262#include <__algorithm/min.h>
1263#include <__algorithm/min_element.h>
1264#include <__algorithm/min_max_result.h>
1265#include <__algorithm/minmax.h>
1266#include <__algorithm/minmax_element.h>
1267#include <__algorithm/mismatch.h>
1268#include <__algorithm/move.h>
1269#include <__algorithm/move_backward.h>
1270#include <__algorithm/next_permutation.h>
1271#include <__algorithm/none_of.h>
1272#include <__algorithm/nth_element.h>
1273#include <__algorithm/partial_sort.h>
1274#include <__algorithm/partial_sort_copy.h>
1275#include <__algorithm/partition.h>
1276#include <__algorithm/partition_copy.h>
1277#include <__algorithm/partition_point.h>
1278#include <__algorithm/pop_heap.h>
1279#include <__algorithm/prev_permutation.h>
1280#include <__algorithm/push_heap.h>
1281#include <__algorithm/ranges_adjacent_find.h>
1282#include <__algorithm/ranges_all_of.h>
1283#include <__algorithm/ranges_any_of.h>
1284#include <__algorithm/ranges_binary_search.h>
1285#include <__algorithm/ranges_copy.h>
1286#include <__algorithm/ranges_copy_backward.h>
1287#include <__algorithm/ranges_copy_if.h>
1288#include <__algorithm/ranges_copy_n.h>
1289#include <__algorithm/ranges_count.h>
1290#include <__algorithm/ranges_count_if.h>
1291#include <__algorithm/ranges_equal.h>
1292#include <__algorithm/ranges_fill.h>
1293#include <__algorithm/ranges_fill_n.h>
1294#include <__algorithm/ranges_find.h>
1295#include <__algorithm/ranges_find_first_of.h>
1296#include <__algorithm/ranges_find_if.h>
1297#include <__algorithm/ranges_find_if_not.h>
1298#include <__algorithm/ranges_for_each.h>
1299#include <__algorithm/ranges_for_each_n.h>
1300#include <__algorithm/ranges_is_partitioned.h>
1301#include <__algorithm/ranges_is_sorted.h>
1302#include <__algorithm/ranges_is_sorted_until.h>
1303#include <__algorithm/ranges_lexicographical_compare.h>
1304#include <__algorithm/ranges_lower_bound.h>
1305#include <__algorithm/ranges_max.h>
1306#include <__algorithm/ranges_max_element.h>
1307#include <__algorithm/ranges_merge.h>
1308#include <__algorithm/ranges_min.h>
1309#include <__algorithm/ranges_min_element.h>
1310#include <__algorithm/ranges_minmax.h>
1311#include <__algorithm/ranges_minmax_element.h>
1312#include <__algorithm/ranges_mismatch.h>
1313#include <__algorithm/ranges_move.h>
1314#include <__algorithm/ranges_move_backward.h>
1315#include <__algorithm/ranges_none_of.h>
1316#include <__algorithm/ranges_remove.h>
1317#include <__algorithm/ranges_remove_if.h>
1318#include <__algorithm/ranges_replace.h>
1319#include <__algorithm/ranges_replace_if.h>
1320#include <__algorithm/ranges_reverse.h>
1321#include <__algorithm/ranges_set_difference.h>
1322#include <__algorithm/ranges_sort.h>
1323#include <__algorithm/ranges_stable_sort.h>
1324#include <__algorithm/ranges_swap_ranges.h>
1325#include <__algorithm/ranges_transform.h>
1326#include <__algorithm/ranges_upper_bound.h>
1327#include <__algorithm/remove.h>
1328#include <__algorithm/remove_copy.h>
1329#include <__algorithm/remove_copy_if.h>
1330#include <__algorithm/remove_if.h>
1331#include <__algorithm/replace.h>
1332#include <__algorithm/replace_copy.h>
1333#include <__algorithm/replace_copy_if.h>
1334#include <__algorithm/replace_if.h>
1335#include <__algorithm/reverse.h>
1336#include <__algorithm/reverse_copy.h>
1337#include <__algorithm/rotate.h>
1338#include <__algorithm/rotate_copy.h>
1339#include <__algorithm/sample.h>
1340#include <__algorithm/search.h>
1341#include <__algorithm/search_n.h>
1342#include <__algorithm/set_difference.h>
1343#include <__algorithm/set_intersection.h>
1344#include <__algorithm/set_symmetric_difference.h>
1345#include <__algorithm/set_union.h>
1346#include <__algorithm/shift_left.h>
1347#include <__algorithm/shift_right.h>
1348#include <__algorithm/shuffle.h>
1349#include <__algorithm/sift_down.h>
1350#include <__algorithm/sort.h>
1351#include <__algorithm/sort_heap.h>
1352#include <__algorithm/stable_partition.h>
1353#include <__algorithm/stable_sort.h>
1354#include <__algorithm/swap_ranges.h>
1355#include <__algorithm/transform.h>
1356#include <__algorithm/unique.h>
1357#include <__algorithm/unique_copy.h>
1358#include <__algorithm/unwrap_iter.h>
1359#include <__algorithm/upper_bound.h>
1360
1361#ifndef _LIBCPP_REMOVE_TRANSITIVE_INCLUDES
1362#  include <chrono>
1363#  include <iterator>
1364#  include <utility>
1365#endif
1366
1367// standard-mandated includes
1368#include <initializer_list>
1369
1370#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
1371#  pragma GCC system_header
1372#endif
1373
1374#if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
1375#   include <__pstl_algorithm>
1376#endif
1377
1378#endif // _LIBCPP_ALGORITHM
1379