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2c1bc4eb PC |
1 | // Algorithm extensions -*- C++ -*- |
2 | ||
ffe94f83 | 3 | // Copyright (C) 2001, 2002 Free Software Foundation, Inc. |
2c1bc4eb PC |
4 | // |
5 | // This file is part of the GNU ISO C++ Library. This library is free | |
6 | // software; you can redistribute it and/or modify it under the | |
7 | // terms of the GNU General Public License as published by the | |
8 | // Free Software Foundation; either version 2, or (at your option) | |
9 | // any later version. | |
10 | ||
11 | // This library is distributed in the hope that it will be useful, | |
12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | // GNU General Public License for more details. | |
15 | ||
16 | // You should have received a copy of the GNU General Public License along | |
17 | // with this library; see the file COPYING. If not, write to the Free | |
18 | // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, | |
19 | // USA. | |
20 | ||
21 | // As a special exception, you may use this file as part of a free software | |
22 | // library without restriction. Specifically, if other files instantiate | |
23 | // templates or use macros or inline functions from this file, or you compile | |
24 | // this file and link it with other files to produce an executable, this | |
25 | // file does not by itself cause the resulting executable to be covered by | |
26 | // the GNU General Public License. This exception does not however | |
27 | // invalidate any other reasons why the executable file might be covered by | |
28 | // the GNU General Public License. | |
29 | ||
30 | /* | |
31 | * | |
32 | * Copyright (c) 1994 | |
33 | * Hewlett-Packard Company | |
34 | * | |
35 | * Permission to use, copy, modify, distribute and sell this software | |
36 | * and its documentation for any purpose is hereby granted without fee, | |
37 | * provided that the above copyright notice appear in all copies and | |
38 | * that both that copyright notice and this permission notice appear | |
39 | * in supporting documentation. Hewlett-Packard Company makes no | |
40 | * representations about the suitability of this software for any | |
41 | * purpose. It is provided "as is" without express or implied warranty. | |
42 | * | |
43 | * | |
44 | * Copyright (c) 1996 | |
45 | * Silicon Graphics Computer Systems, Inc. | |
46 | * | |
47 | * Permission to use, copy, modify, distribute and sell this software | |
48 | * and its documentation for any purpose is hereby granted without fee, | |
49 | * provided that the above copyright notice appear in all copies and | |
50 | * that both that copyright notice and this permission notice appear | |
51 | * in supporting documentation. Silicon Graphics makes no | |
52 | * representations about the suitability of this software for any | |
53 | * purpose. It is provided "as is" without express or implied warranty. | |
54 | */ | |
55 | ||
ffe94f83 PE |
56 | /** @file ext/algorithm |
57 | * This file is a GNU extension to the Standard C++ Library (possibly | |
58 | * containing extensions from the HP/SGI STL subset). You should only | |
59 | * include this header if you are using GCC 3 or later. | |
60 | */ | |
61 | ||
2c1bc4eb | 62 | #ifndef _EXT_ALGORITHM |
3d7c150e | 63 | #define _EXT_ALGORITHM 1 |
2c1bc4eb | 64 | |
36955a95 | 65 | #pragma GCC system_header |
3d7c150e | 66 | |
54c1bf78 | 67 | #include <algorithm> |
2c1bc4eb PC |
68 | |
69 | namespace __gnu_cxx | |
70 | { | |
f53d0ff1 PC |
71 | using std::ptrdiff_t; |
72 | using std::min; | |
73 | using std::pair; | |
74 | using std::input_iterator_tag; | |
75 | using std::random_access_iterator_tag; | |
76 | using std::iterator_traits; | |
77 | ||
78 | //-------------------------------------------------- | |
79 | // copy_n (not part of the C++ standard) | |
80 | ||
08addde6 PE |
81 | template<typename _InputIterator, typename _Size, typename _OutputIterator> |
82 | pair<_InputIterator, _OutputIterator> | |
83 | __copy_n(_InputIterator __first, _Size __count, | |
84 | _OutputIterator __result, | |
f53d0ff1 PC |
85 | input_iterator_tag) |
86 | { | |
87 | for ( ; __count > 0; --__count) { | |
88 | *__result = *__first; | |
89 | ++__first; | |
90 | ++__result; | |
91 | } | |
08addde6 | 92 | return pair<_InputIterator, _OutputIterator>(__first, __result); |
f53d0ff1 PC |
93 | } |
94 | ||
08addde6 PE |
95 | template<typename _RAIterator, typename _Size, typename _OutputIterator> |
96 | inline pair<_RAIterator, _OutputIterator> | |
97 | __copy_n(_RAIterator __first, _Size __count, | |
98 | _OutputIterator __result, | |
f53d0ff1 PC |
99 | random_access_iterator_tag) |
100 | { | |
08addde6 PE |
101 | _RAIterator __last = __first + __count; |
102 | return pair<_RAIterator, _OutputIterator>(__last, | |
f53d0ff1 PC |
103 | std::copy(__first, __last, __result)); |
104 | } | |
105 | ||
106 | /** | |
107 | * @brief Copies the range [first,first+count) into [result,result+count). | |
108 | * @param first An input iterator. | |
109 | * @param count The number of elements to copy. | |
110 | * @param result An output iterator. | |
111 | * @return A std::pair composed of first+count and result+count. | |
112 | * | |
113 | * This is an SGI extension. | |
114 | * This inline function will boil down to a call to @c memmove whenever | |
115 | * possible. Failing that, if random access iterators are passed, then the | |
116 | * loop count will be known (and therefore a candidate for compiler | |
117 | * optimizations such as unrolling). | |
118 | * @ingroup SGIextensions | |
119 | */ | |
08addde6 PE |
120 | template<typename _InputIterator, typename _Size, typename _OutputIterator> |
121 | inline pair<_InputIterator, _OutputIterator> | |
122 | copy_n(_InputIterator __first, _Size __count, _OutputIterator __result) | |
f53d0ff1 PC |
123 | { |
124 | // concept requirements | |
3d7c150e BK |
125 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) |
126 | __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, | |
08addde6 | 127 | typename iterator_traits<_InputIterator>::value_type>) |
f53d0ff1 PC |
128 | |
129 | return __copy_n(__first, __count, __result, | |
130 | std::__iterator_category(__first)); | |
131 | } | |
132 | ||
08addde6 | 133 | template<typename _InputIterator1, typename _InputIterator2> |
f53d0ff1 | 134 | int |
08addde6 PE |
135 | __lexicographical_compare_3way(_InputIterator1 __first1, _InputIterator1 __last1, |
136 | _InputIterator2 __first2, _InputIterator2 __last2) | |
f53d0ff1 PC |
137 | { |
138 | while (__first1 != __last1 && __first2 != __last2) { | |
139 | if (*__first1 < *__first2) | |
140 | return -1; | |
141 | if (*__first2 < *__first1) | |
142 | return 1; | |
143 | ++__first1; | |
144 | ++__first2; | |
145 | } | |
146 | if (__first2 == __last2) { | |
147 | return !(__first1 == __last1); | |
148 | } | |
149 | else { | |
150 | return -1; | |
151 | } | |
152 | } | |
153 | ||
154 | inline int | |
155 | __lexicographical_compare_3way(const unsigned char* __first1, | |
156 | const unsigned char* __last1, | |
157 | const unsigned char* __first2, | |
158 | const unsigned char* __last2) | |
159 | { | |
160 | const ptrdiff_t __len1 = __last1 - __first1; | |
161 | const ptrdiff_t __len2 = __last2 - __first2; | |
162 | const int __result = std::memcmp(__first1, __first2, min(__len1, __len2)); | |
163 | return __result != 0 ? __result | |
164 | : (__len1 == __len2 ? 0 : (__len1 < __len2 ? -1 : 1)); | |
165 | } | |
166 | ||
167 | inline int | |
168 | __lexicographical_compare_3way(const char* __first1, const char* __last1, | |
169 | const char* __first2, const char* __last2) | |
170 | { | |
171 | #if CHAR_MAX == SCHAR_MAX | |
172 | return __lexicographical_compare_3way( | |
173 | (const signed char*) __first1, | |
174 | (const signed char*) __last1, | |
175 | (const signed char*) __first2, | |
176 | (const signed char*) __last2); | |
177 | #else | |
178 | return __lexicographical_compare_3way((const unsigned char*) __first1, | |
179 | (const unsigned char*) __last1, | |
180 | (const unsigned char*) __first2, | |
181 | (const unsigned char*) __last2); | |
182 | #endif | |
183 | } | |
184 | ||
185 | /** | |
186 | * @brief @c memcmp on steroids. | |
187 | * @param first1 An input iterator. | |
188 | * @param last1 An input iterator. | |
189 | * @param first2 An input iterator. | |
190 | * @param last2 An input iterator. | |
191 | * @return An int, as with @c memcmp. | |
192 | * | |
193 | * The return value will be less than zero if the first range is | |
194 | * "lexigraphically less than" the second, greater than zero if the second | |
195 | * range is "lexigraphically less than" the first, and zero otherwise. | |
196 | * This is an SGI extension. | |
197 | * @ingroup SGIextensions | |
198 | */ | |
08addde6 | 199 | template<typename _InputIterator1, typename _InputIterator2> |
f53d0ff1 | 200 | int |
08addde6 PE |
201 | lexicographical_compare_3way(_InputIterator1 __first1, _InputIterator1 __last1, |
202 | _InputIterator2 __first2, _InputIterator2 __last2) | |
f53d0ff1 PC |
203 | { |
204 | // concept requirements | |
3d7c150e BK |
205 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) |
206 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) | |
207 | __glibcxx_function_requires(_LessThanComparableConcept< | |
08addde6 | 208 | typename iterator_traits<_InputIterator1>::value_type>) |
3d7c150e | 209 | __glibcxx_function_requires(_LessThanComparableConcept< |
08addde6 | 210 | typename iterator_traits<_InputIterator2>::value_type>) |
285b36d6 BK |
211 | __glibcxx_requires_valid_range(__first1, __last1); |
212 | __glibcxx_requires_valid_range(__first2, __last2); | |
f53d0ff1 PC |
213 | |
214 | return __lexicographical_compare_3way(__first1, __last1, __first2, __last2); | |
215 | } | |
216 | ||
2c1bc4eb PC |
217 | // count and count_if: this version, whose return type is void, was present |
218 | // in the HP STL, and is retained as an extension for backward compatibility. | |
219 | ||
08addde6 | 220 | template<typename _InputIterator, typename _Tp, typename _Size> |
2c1bc4eb | 221 | void |
08addde6 | 222 | count(_InputIterator __first, _InputIterator __last, |
2c1bc4eb PC |
223 | const _Tp& __value, |
224 | _Size& __n) | |
225 | { | |
226 | // concept requirements | |
3d7c150e BK |
227 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) |
228 | __glibcxx_function_requires(_EqualityComparableConcept< | |
08addde6 | 229 | typename iterator_traits<_InputIterator>::value_type >) |
3d7c150e | 230 | __glibcxx_function_requires(_EqualityComparableConcept<_Tp>) |
285b36d6 BK |
231 | __glibcxx_requires_valid_range(__first, __last); |
232 | ||
2c1bc4eb PC |
233 | for ( ; __first != __last; ++__first) |
234 | if (*__first == __value) | |
235 | ++__n; | |
236 | } | |
237 | ||
08addde6 | 238 | template<typename _InputIterator, typename _Predicate, typename _Size> |
2c1bc4eb | 239 | void |
08addde6 | 240 | count_if(_InputIterator __first, _InputIterator __last, |
2c1bc4eb PC |
241 | _Predicate __pred, |
242 | _Size& __n) | |
243 | { | |
244 | // concept requirements | |
3d7c150e BK |
245 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) |
246 | __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate, | |
08addde6 | 247 | typename iterator_traits<_InputIterator>::value_type>) |
285b36d6 BK |
248 | __glibcxx_requires_valid_range(__first, __last); |
249 | ||
2c1bc4eb PC |
250 | for ( ; __first != __last; ++__first) |
251 | if (__pred(*__first)) | |
252 | ++__n; | |
253 | } | |
254 | ||
255 | // random_sample and random_sample_n (extensions, not part of the standard). | |
256 | ||
fc7f0a80 PE |
257 | /** |
258 | * This is an SGI extension. | |
259 | * @ingroup SGIextensions | |
260 | * @doctodo | |
261 | */ | |
08addde6 PE |
262 | template<typename _ForwardIterator, typename _OutputIterator, typename _Distance> |
263 | _OutputIterator | |
264 | random_sample_n(_ForwardIterator __first, _ForwardIterator __last, | |
265 | _OutputIterator __out, const _Distance __n) | |
2c1bc4eb PC |
266 | { |
267 | // concept requirements | |
3d7c150e BK |
268 | __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) |
269 | __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, | |
08addde6 | 270 | typename iterator_traits<_ForwardIterator>::value_type>) |
285b36d6 | 271 | __glibcxx_requires_valid_range(__first, __last); |
2c1bc4eb PC |
272 | |
273 | _Distance __remaining = std::distance(__first, __last); | |
f53d0ff1 | 274 | _Distance __m = min(__n, __remaining); |
2c1bc4eb PC |
275 | |
276 | while (__m > 0) { | |
82fa4538 | 277 | if ((std::rand() % __remaining) < __m) { |
2c1bc4eb PC |
278 | *__out = *__first; |
279 | ++__out; | |
280 | --__m; | |
281 | } | |
282 | ||
283 | --__remaining; | |
284 | ++__first; | |
285 | } | |
286 | return __out; | |
287 | } | |
288 | ||
fc7f0a80 PE |
289 | /** |
290 | * This is an SGI extension. | |
291 | * @ingroup SGIextensions | |
292 | * @doctodo | |
293 | */ | |
08addde6 | 294 | template<typename _ForwardIterator, typename _OutputIterator, typename _Distance, |
2c1bc4eb | 295 | typename _RandomNumberGenerator> |
08addde6 PE |
296 | _OutputIterator |
297 | random_sample_n(_ForwardIterator __first, _ForwardIterator __last, | |
298 | _OutputIterator __out, const _Distance __n, | |
2c1bc4eb PC |
299 | _RandomNumberGenerator& __rand) |
300 | { | |
301 | // concept requirements | |
3d7c150e BK |
302 | __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) |
303 | __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, | |
08addde6 | 304 | typename iterator_traits<_ForwardIterator>::value_type>) |
3d7c150e | 305 | __glibcxx_function_requires(_UnaryFunctionConcept< |
2c1bc4eb | 306 | _RandomNumberGenerator, _Distance, _Distance>) |
285b36d6 | 307 | __glibcxx_requires_valid_range(__first, __last); |
2c1bc4eb PC |
308 | |
309 | _Distance __remaining = std::distance(__first, __last); | |
f53d0ff1 | 310 | _Distance __m = min(__n, __remaining); |
2c1bc4eb PC |
311 | |
312 | while (__m > 0) { | |
313 | if (__rand(__remaining) < __m) { | |
314 | *__out = *__first; | |
315 | ++__out; | |
316 | --__m; | |
317 | } | |
318 | ||
319 | --__remaining; | |
320 | ++__first; | |
321 | } | |
322 | return __out; | |
323 | } | |
324 | ||
08addde6 PE |
325 | template<typename _InputIterator, typename _RandomAccessIterator, typename _Distance> |
326 | _RandomAccessIterator | |
327 | __random_sample(_InputIterator __first, _InputIterator __last, | |
328 | _RandomAccessIterator __out, | |
2c1bc4eb PC |
329 | const _Distance __n) |
330 | { | |
331 | _Distance __m = 0; | |
332 | _Distance __t = __n; | |
333 | for ( ; __first != __last && __m < __n; ++__m, ++__first) | |
334 | __out[__m] = *__first; | |
335 | ||
336 | while (__first != __last) { | |
337 | ++__t; | |
82fa4538 | 338 | _Distance __M = std::rand() % (__t); |
2c1bc4eb PC |
339 | if (__M < __n) |
340 | __out[__M] = *__first; | |
341 | ++__first; | |
342 | } | |
343 | ||
344 | return __out + __m; | |
345 | } | |
346 | ||
08addde6 | 347 | template<typename _InputIterator, typename _RandomAccessIterator, |
2c1bc4eb | 348 | typename _RandomNumberGenerator, typename _Distance> |
08addde6 PE |
349 | _RandomAccessIterator |
350 | __random_sample(_InputIterator __first, _InputIterator __last, | |
351 | _RandomAccessIterator __out, | |
2c1bc4eb PC |
352 | _RandomNumberGenerator& __rand, |
353 | const _Distance __n) | |
354 | { | |
355 | // concept requirements | |
3d7c150e | 356 | __glibcxx_function_requires(_UnaryFunctionConcept< |
2c1bc4eb PC |
357 | _RandomNumberGenerator, _Distance, _Distance>) |
358 | ||
359 | _Distance __m = 0; | |
360 | _Distance __t = __n; | |
361 | for ( ; __first != __last && __m < __n; ++__m, ++__first) | |
362 | __out[__m] = *__first; | |
363 | ||
364 | while (__first != __last) { | |
365 | ++__t; | |
366 | _Distance __M = __rand(__t); | |
367 | if (__M < __n) | |
368 | __out[__M] = *__first; | |
369 | ++__first; | |
370 | } | |
371 | ||
372 | return __out + __m; | |
373 | } | |
374 | ||
fc7f0a80 PE |
375 | /** |
376 | * This is an SGI extension. | |
377 | * @ingroup SGIextensions | |
378 | * @doctodo | |
379 | */ | |
08addde6 PE |
380 | template<typename _InputIterator, typename _RandomAccessIterator> |
381 | inline _RandomAccessIterator | |
382 | random_sample(_InputIterator __first, _InputIterator __last, | |
383 | _RandomAccessIterator __out_first, _RandomAccessIterator __out_last) | |
2c1bc4eb PC |
384 | { |
385 | // concept requirements | |
3d7c150e BK |
386 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) |
387 | __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< | |
08addde6 | 388 | _RandomAccessIterator>) |
285b36d6 BK |
389 | __glibcxx_requires_valid_range(__first, __last); |
390 | __glibcxx_requires_valid_range(__out_first, __out_last); | |
2c1bc4eb PC |
391 | |
392 | return __random_sample(__first, __last, | |
393 | __out_first, __out_last - __out_first); | |
394 | } | |
395 | ||
fc7f0a80 PE |
396 | /** |
397 | * This is an SGI extension. | |
398 | * @ingroup SGIextensions | |
399 | * @doctodo | |
400 | */ | |
08addde6 | 401 | template<typename _InputIterator, typename _RandomAccessIterator, |
2c1bc4eb | 402 | typename _RandomNumberGenerator> |
08addde6 PE |
403 | inline _RandomAccessIterator |
404 | random_sample(_InputIterator __first, _InputIterator __last, | |
405 | _RandomAccessIterator __out_first, _RandomAccessIterator __out_last, | |
2c1bc4eb PC |
406 | _RandomNumberGenerator& __rand) |
407 | { | |
408 | // concept requirements | |
3d7c150e BK |
409 | __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) |
410 | __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< | |
08addde6 | 411 | _RandomAccessIterator>) |
285b36d6 BK |
412 | __glibcxx_requires_valid_range(__first, __last); |
413 | __glibcxx_requires_valid_range(__out_first, __out_last); | |
2c1bc4eb PC |
414 | |
415 | return __random_sample(__first, __last, | |
416 | __out_first, __rand, | |
417 | __out_last - __out_first); | |
418 | } | |
419 | ||
fc7f0a80 PE |
420 | /** |
421 | * This is an SGI extension. | |
422 | * @ingroup SGIextensions | |
423 | * @doctodo | |
424 | */ | |
08addde6 | 425 | template<typename _RandomAccessIterator> |
2c1bc4eb | 426 | inline bool |
08addde6 | 427 | is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) |
2c1bc4eb PC |
428 | { |
429 | // concept requirements | |
3d7c150e BK |
430 | __glibcxx_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>) |
431 | __glibcxx_function_requires(_LessThanComparableConcept< | |
08addde6 | 432 | typename iterator_traits<_RandomAccessIterator>::value_type>) |
285b36d6 | 433 | __glibcxx_requires_valid_range(__first, __last); |
2c1bc4eb | 434 | |
285b36d6 | 435 | return std::__is_heap(__first, __last - __first); |
2c1bc4eb PC |
436 | } |
437 | ||
fc7f0a80 PE |
438 | /** |
439 | * This is an SGI extension. | |
440 | * @ingroup SGIextensions | |
441 | * @doctodo | |
442 | */ | |
08addde6 | 443 | template<typename _RandomAccessIterator, typename _StrictWeakOrdering> |
2c1bc4eb | 444 | inline bool |
08addde6 | 445 | is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, |
2c1bc4eb PC |
446 | _StrictWeakOrdering __comp) |
447 | { | |
448 | // concept requirements | |
3d7c150e BK |
449 | __glibcxx_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>) |
450 | __glibcxx_function_requires(_BinaryPredicateConcept<_StrictWeakOrdering, | |
08addde6 PE |
451 | typename iterator_traits<_RandomAccessIterator>::value_type, |
452 | typename iterator_traits<_RandomAccessIterator>::value_type>) | |
285b36d6 | 453 | __glibcxx_requires_valid_range(__first, __last); |
2c1bc4eb | 454 | |
285b36d6 | 455 | return std::__is_heap(__first, __comp, __last - __first); |
2c1bc4eb PC |
456 | } |
457 | ||
458 | // is_sorted, a predicated testing whether a range is sorted in | |
459 | // nondescending order. This is an extension, not part of the C++ | |
460 | // standard. | |
461 | ||
fc7f0a80 PE |
462 | /** |
463 | * This is an SGI extension. | |
464 | * @ingroup SGIextensions | |
465 | * @doctodo | |
466 | */ | |
08addde6 | 467 | template<typename _ForwardIterator> |
2c1bc4eb | 468 | bool |
08addde6 | 469 | is_sorted(_ForwardIterator __first, _ForwardIterator __last) |
2c1bc4eb PC |
470 | { |
471 | // concept requirements | |
3d7c150e BK |
472 | __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) |
473 | __glibcxx_function_requires(_LessThanComparableConcept< | |
08addde6 | 474 | typename iterator_traits<_ForwardIterator>::value_type>) |
285b36d6 | 475 | __glibcxx_requires_valid_range(__first, __last); |
2c1bc4eb PC |
476 | |
477 | if (__first == __last) | |
478 | return true; | |
479 | ||
08addde6 | 480 | _ForwardIterator __next = __first; |
2c1bc4eb PC |
481 | for (++__next; __next != __last; __first = __next, ++__next) { |
482 | if (*__next < *__first) | |
483 | return false; | |
484 | } | |
485 | ||
486 | return true; | |
487 | } | |
488 | ||
fc7f0a80 PE |
489 | /** |
490 | * This is an SGI extension. | |
491 | * @ingroup SGIextensions | |
492 | * @doctodo | |
493 | */ | |
08addde6 | 494 | template<typename _ForwardIterator, typename _StrictWeakOrdering> |
2c1bc4eb | 495 | bool |
08addde6 | 496 | is_sorted(_ForwardIterator __first, _ForwardIterator __last, _StrictWeakOrdering __comp) |
2c1bc4eb PC |
497 | { |
498 | // concept requirements | |
3d7c150e BK |
499 | __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) |
500 | __glibcxx_function_requires(_BinaryPredicateConcept<_StrictWeakOrdering, | |
08addde6 PE |
501 | typename iterator_traits<_ForwardIterator>::value_type, |
502 | typename iterator_traits<_ForwardIterator>::value_type>) | |
285b36d6 | 503 | __glibcxx_requires_valid_range(__first, __last); |
2c1bc4eb PC |
504 | |
505 | if (__first == __last) | |
506 | return true; | |
507 | ||
08addde6 | 508 | _ForwardIterator __next = __first; |
2c1bc4eb PC |
509 | for (++__next; __next != __last; __first = __next, ++__next) { |
510 | if (__comp(*__next, *__first)) | |
511 | return false; | |
512 | } | |
513 | ||
514 | return true; | |
515 | } | |
2c1bc4eb PC |
516 | } // namespace __gnu_cxx |
517 | ||
518 | #endif /* _EXT_ALGORITHM */ |