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stl_move.h (_GLIBCXX_MOVE): Add.
[gcc.git] / libstdc++-v3 / include / bits / stl_algo.h
1 // Algorithm implementation -*- C++ -*-
2
3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 // Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 2, or (at your option)
10 // any later version.
11
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16
17 // You should have received a copy of the GNU General Public License along
18 // with this library; see the file COPYING. If not, write to the Free
19 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
20 // USA.
21
22 // As a special exception, you may use this file as part of a free software
23 // library without restriction. Specifically, if other files instantiate
24 // templates or use macros or inline functions from this file, or you compile
25 // this file and link it with other files to produce an executable, this
26 // file does not by itself cause the resulting executable to be covered by
27 // the GNU General Public License. This exception does not however
28 // invalidate any other reasons why the executable file might be covered by
29 // the GNU General Public License.
30
31 /*
32 *
33 * Copyright (c) 1994
34 * Hewlett-Packard Company
35 *
36 * Permission to use, copy, modify, distribute and sell this software
37 * and its documentation for any purpose is hereby granted without fee,
38 * provided that the above copyright notice appear in all copies and
39 * that both that copyright notice and this permission notice appear
40 * in supporting documentation. Hewlett-Packard Company makes no
41 * representations about the suitability of this software for any
42 * purpose. It is provided "as is" without express or implied warranty.
43 *
44 *
45 * Copyright (c) 1996
46 * Silicon Graphics Computer Systems, Inc.
47 *
48 * Permission to use, copy, modify, distribute and sell this software
49 * and its documentation for any purpose is hereby granted without fee,
50 * provided that the above copyright notice appear in all copies and
51 * that both that copyright notice and this permission notice appear
52 * in supporting documentation. Silicon Graphics makes no
53 * representations about the suitability of this software for any
54 * purpose. It is provided "as is" without express or implied warranty.
55 */
56
57 /** @file stl_algo.h
58 * This is an internal header file, included by other library headers.
59 * You should not attempt to use it directly.
60 */
61
62 #ifndef _STL_ALGO_H
63 #define _STL_ALGO_H 1
64
65 #include <cstdlib> // for rand
66 #include <bits/stl_heap.h>
67 #include <bits/stl_tempbuf.h> // for _Temporary_buffer
68 #include <bits/algorithmfwd.h>
69 #include <debug/debug.h>
70
71 // See concept_check.h for the __glibcxx_*_requires macros.
72
73 _GLIBCXX_BEGIN_NAMESPACE(std)
74
75 /**
76 * @brief Find the median of three values.
77 * @param a A value.
78 * @param b A value.
79 * @param c A value.
80 * @return One of @p a, @p b or @p c.
81 *
82 * If @c {l,m,n} is some convolution of @p {a,b,c} such that @c l<=m<=n
83 * then the value returned will be @c m.
84 * This is an SGI extension.
85 * @ingroup SGIextensions
86 */
87 template<typename _Tp>
88 inline const _Tp&
89 __median(const _Tp& __a, const _Tp& __b, const _Tp& __c)
90 {
91 // concept requirements
92 __glibcxx_function_requires(_LessThanComparableConcept<_Tp>)
93 if (__a < __b)
94 if (__b < __c)
95 return __b;
96 else if (__a < __c)
97 return __c;
98 else
99 return __a;
100 else if (__a < __c)
101 return __a;
102 else if (__b < __c)
103 return __c;
104 else
105 return __b;
106 }
107
108 /**
109 * @brief Find the median of three values using a predicate for comparison.
110 * @param a A value.
111 * @param b A value.
112 * @param c A value.
113 * @param comp A binary predicate.
114 * @return One of @p a, @p b or @p c.
115 *
116 * If @c {l,m,n} is some convolution of @p {a,b,c} such that @p comp(l,m)
117 * and @p comp(m,n) are both true then the value returned will be @c m.
118 * This is an SGI extension.
119 * @ingroup SGIextensions
120 */
121 template<typename _Tp, typename _Compare>
122 inline const _Tp&
123 __median(const _Tp& __a, const _Tp& __b, const _Tp& __c, _Compare __comp)
124 {
125 // concept requirements
126 __glibcxx_function_requires(_BinaryFunctionConcept<_Compare, bool,
127 _Tp, _Tp>)
128 if (__comp(__a, __b))
129 if (__comp(__b, __c))
130 return __b;
131 else if (__comp(__a, __c))
132 return __c;
133 else
134 return __a;
135 else if (__comp(__a, __c))
136 return __a;
137 else if (__comp(__b, __c))
138 return __c;
139 else
140 return __b;
141 }
142
143 // for_each
144
145 /**
146 * @if maint
147 * This is an overload used by find() for the Input Iterator case.
148 * @endif
149 */
150 template<typename _InputIterator, typename _Tp>
151 inline _InputIterator
152 __find(_InputIterator __first, _InputIterator __last,
153 const _Tp& __val, input_iterator_tag)
154 {
155 while (__first != __last && !(*__first == __val))
156 ++__first;
157 return __first;
158 }
159
160 /**
161 * @if maint
162 * This is an overload used by find_if() for the Input Iterator case.
163 * @endif
164 */
165 template<typename _InputIterator, typename _Predicate>
166 inline _InputIterator
167 __find_if(_InputIterator __first, _InputIterator __last,
168 _Predicate __pred, input_iterator_tag)
169 {
170 while (__first != __last && !bool(__pred(*__first)))
171 ++__first;
172 return __first;
173 }
174
175 /**
176 * @if maint
177 * This is an overload used by find() for the RAI case.
178 * @endif
179 */
180 template<typename _RandomAccessIterator, typename _Tp>
181 _RandomAccessIterator
182 __find(_RandomAccessIterator __first, _RandomAccessIterator __last,
183 const _Tp& __val, random_access_iterator_tag)
184 {
185 typename iterator_traits<_RandomAccessIterator>::difference_type
186 __trip_count = (__last - __first) >> 2;
187
188 for (; __trip_count > 0; --__trip_count)
189 {
190 if (*__first == __val)
191 return __first;
192 ++__first;
193
194 if (*__first == __val)
195 return __first;
196 ++__first;
197
198 if (*__first == __val)
199 return __first;
200 ++__first;
201
202 if (*__first == __val)
203 return __first;
204 ++__first;
205 }
206
207 switch (__last - __first)
208 {
209 case 3:
210 if (*__first == __val)
211 return __first;
212 ++__first;
213 case 2:
214 if (*__first == __val)
215 return __first;
216 ++__first;
217 case 1:
218 if (*__first == __val)
219 return __first;
220 ++__first;
221 case 0:
222 default:
223 return __last;
224 }
225 }
226
227 /**
228 * @if maint
229 * This is an overload used by find_if() for the RAI case.
230 * @endif
231 */
232 template<typename _RandomAccessIterator, typename _Predicate>
233 _RandomAccessIterator
234 __find_if(_RandomAccessIterator __first, _RandomAccessIterator __last,
235 _Predicate __pred, random_access_iterator_tag)
236 {
237 typename iterator_traits<_RandomAccessIterator>::difference_type
238 __trip_count = (__last - __first) >> 2;
239
240 for (; __trip_count > 0; --__trip_count)
241 {
242 if (__pred(*__first))
243 return __first;
244 ++__first;
245
246 if (__pred(*__first))
247 return __first;
248 ++__first;
249
250 if (__pred(*__first))
251 return __first;
252 ++__first;
253
254 if (__pred(*__first))
255 return __first;
256 ++__first;
257 }
258
259 switch (__last - __first)
260 {
261 case 3:
262 if (__pred(*__first))
263 return __first;
264 ++__first;
265 case 2:
266 if (__pred(*__first))
267 return __first;
268 ++__first;
269 case 1:
270 if (__pred(*__first))
271 return __first;
272 ++__first;
273 case 0:
274 default:
275 return __last;
276 }
277 }
278
279 // set_difference
280 // set_intersection
281 // set_symmetric_difference
282 // set_union
283 // for_each
284 // find
285 // find_if
286 // find_first_of
287 // adjacent_find
288 // count
289 // count_if
290 // search
291
292 /**
293 * @if maint
294 * This is an uglified
295 * search_n(_ForwardIterator, _ForwardIterator, _Integer, const _Tp&)
296 * overloaded for forward iterators.
297 * @endif
298 */
299 template<typename _ForwardIterator, typename _Integer, typename _Tp>
300 _ForwardIterator
301 __search_n(_ForwardIterator __first, _ForwardIterator __last,
302 _Integer __count, const _Tp& __val,
303 std::forward_iterator_tag)
304 {
305 __first = _GLIBCXX_STD_P::find(__first, __last, __val);
306 while (__first != __last)
307 {
308 typename iterator_traits<_ForwardIterator>::difference_type
309 __n = __count;
310 _ForwardIterator __i = __first;
311 ++__i;
312 while (__i != __last && __n != 1 && *__i == __val)
313 {
314 ++__i;
315 --__n;
316 }
317 if (__n == 1)
318 return __first;
319 if (__i == __last)
320 return __last;
321 __first = _GLIBCXX_STD_P::find(++__i, __last, __val);
322 }
323 return __last;
324 }
325
326 /**
327 * @if maint
328 * This is an uglified
329 * search_n(_ForwardIterator, _ForwardIterator, _Integer, const _Tp&)
330 * overloaded for random access iterators.
331 * @endif
332 */
333 template<typename _RandomAccessIter, typename _Integer, typename _Tp>
334 _RandomAccessIter
335 __search_n(_RandomAccessIter __first, _RandomAccessIter __last,
336 _Integer __count, const _Tp& __val,
337 std::random_access_iterator_tag)
338 {
339
340 typedef typename std::iterator_traits<_RandomAccessIter>::difference_type
341 _DistanceType;
342
343 _DistanceType __tailSize = __last - __first;
344 const _DistanceType __pattSize = __count;
345
346 if (__tailSize < __pattSize)
347 return __last;
348
349 const _DistanceType __skipOffset = __pattSize - 1;
350 _RandomAccessIter __lookAhead = __first + __skipOffset;
351 __tailSize -= __pattSize;
352
353 while (1) // the main loop...
354 {
355 // __lookAhead here is always pointing to the last element of next
356 // possible match.
357 while (!(*__lookAhead == __val)) // the skip loop...
358 {
359 if (__tailSize < __pattSize)
360 return __last; // Failure
361 __lookAhead += __pattSize;
362 __tailSize -= __pattSize;
363 }
364 _DistanceType __remainder = __skipOffset;
365 for (_RandomAccessIter __backTrack = __lookAhead - 1;
366 *__backTrack == __val; --__backTrack)
367 {
368 if (--__remainder == 0)
369 return (__lookAhead - __skipOffset); // Success
370 }
371 if (__remainder > __tailSize)
372 return __last; // Failure
373 __lookAhead += __remainder;
374 __tailSize -= __remainder;
375 }
376 }
377
378 // search_n
379
380 /**
381 * @if maint
382 * This is an uglified
383 * search_n(_ForwardIterator, _ForwardIterator, _Integer, const _Tp&,
384 * _BinaryPredicate)
385 * overloaded for forward iterators.
386 * @endif
387 */
388 template<typename _ForwardIterator, typename _Integer, typename _Tp,
389 typename _BinaryPredicate>
390 _ForwardIterator
391 __search_n(_ForwardIterator __first, _ForwardIterator __last,
392 _Integer __count, const _Tp& __val,
393 _BinaryPredicate __binary_pred, std::forward_iterator_tag)
394 {
395 while (__first != __last && !bool(__binary_pred(*__first, __val)))
396 ++__first;
397
398 while (__first != __last)
399 {
400 typename iterator_traits<_ForwardIterator>::difference_type
401 __n = __count;
402 _ForwardIterator __i = __first;
403 ++__i;
404 while (__i != __last && __n != 1 && bool(__binary_pred(*__i, __val)))
405 {
406 ++__i;
407 --__n;
408 }
409 if (__n == 1)
410 return __first;
411 if (__i == __last)
412 return __last;
413 __first = ++__i;
414 while (__first != __last
415 && !bool(__binary_pred(*__first, __val)))
416 ++__first;
417 }
418 return __last;
419 }
420
421 /**
422 * @if maint
423 * This is an uglified
424 * search_n(_ForwardIterator, _ForwardIterator, _Integer, const _Tp&,
425 * _BinaryPredicate)
426 * overloaded for random access iterators.
427 * @endif
428 */
429 template<typename _RandomAccessIter, typename _Integer, typename _Tp,
430 typename _BinaryPredicate>
431 _RandomAccessIter
432 __search_n(_RandomAccessIter __first, _RandomAccessIter __last,
433 _Integer __count, const _Tp& __val,
434 _BinaryPredicate __binary_pred, std::random_access_iterator_tag)
435 {
436
437 typedef typename std::iterator_traits<_RandomAccessIter>::difference_type
438 _DistanceType;
439
440 _DistanceType __tailSize = __last - __first;
441 const _DistanceType __pattSize = __count;
442
443 if (__tailSize < __pattSize)
444 return __last;
445
446 const _DistanceType __skipOffset = __pattSize - 1;
447 _RandomAccessIter __lookAhead = __first + __skipOffset;
448 __tailSize -= __pattSize;
449
450 while (1) // the main loop...
451 {
452 // __lookAhead here is always pointing to the last element of next
453 // possible match.
454 while (!bool(__binary_pred(*__lookAhead, __val))) // the skip loop...
455 {
456 if (__tailSize < __pattSize)
457 return __last; // Failure
458 __lookAhead += __pattSize;
459 __tailSize -= __pattSize;
460 }
461 _DistanceType __remainder = __skipOffset;
462 for (_RandomAccessIter __backTrack = __lookAhead - 1;
463 __binary_pred(*__backTrack, __val); --__backTrack)
464 {
465 if (--__remainder == 0)
466 return (__lookAhead - __skipOffset); // Success
467 }
468 if (__remainder > __tailSize)
469 return __last; // Failure
470 __lookAhead += __remainder;
471 __tailSize -= __remainder;
472 }
473 }
474
475 // find_end for forward iterators.
476 template<typename _ForwardIterator1, typename _ForwardIterator2>
477 _ForwardIterator1
478 __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
479 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
480 forward_iterator_tag, forward_iterator_tag)
481 {
482 if (__first2 == __last2)
483 return __last1;
484 else
485 {
486 _ForwardIterator1 __result = __last1;
487 while (1)
488 {
489 _ForwardIterator1 __new_result
490 = _GLIBCXX_STD_P::search(__first1, __last1, __first2, __last2);
491 if (__new_result == __last1)
492 return __result;
493 else
494 {
495 __result = __new_result;
496 __first1 = __new_result;
497 ++__first1;
498 }
499 }
500 }
501 }
502
503 template<typename _ForwardIterator1, typename _ForwardIterator2,
504 typename _BinaryPredicate>
505 _ForwardIterator1
506 __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
507 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
508 forward_iterator_tag, forward_iterator_tag,
509 _BinaryPredicate __comp)
510 {
511 if (__first2 == __last2)
512 return __last1;
513 else
514 {
515 _ForwardIterator1 __result = __last1;
516 while (1)
517 {
518 _ForwardIterator1 __new_result
519 = _GLIBCXX_STD_P::search(__first1, __last1, __first2,
520 __last2, __comp);
521 if (__new_result == __last1)
522 return __result;
523 else
524 {
525 __result = __new_result;
526 __first1 = __new_result;
527 ++__first1;
528 }
529 }
530 }
531 }
532
533 // find_end for bidirectional iterators (much faster).
534 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2>
535 _BidirectionalIterator1
536 __find_end(_BidirectionalIterator1 __first1,
537 _BidirectionalIterator1 __last1,
538 _BidirectionalIterator2 __first2,
539 _BidirectionalIterator2 __last2,
540 bidirectional_iterator_tag, bidirectional_iterator_tag)
541 {
542 // concept requirements
543 __glibcxx_function_requires(_BidirectionalIteratorConcept<
544 _BidirectionalIterator1>)
545 __glibcxx_function_requires(_BidirectionalIteratorConcept<
546 _BidirectionalIterator2>)
547
548 typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1;
549 typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2;
550
551 _RevIterator1 __rlast1(__first1);
552 _RevIterator2 __rlast2(__first2);
553 _RevIterator1 __rresult = _GLIBCXX_STD_P::search(_RevIterator1(__last1),
554 __rlast1,
555 _RevIterator2(__last2),
556 __rlast2);
557
558 if (__rresult == __rlast1)
559 return __last1;
560 else
561 {
562 _BidirectionalIterator1 __result = __rresult.base();
563 std::advance(__result, -std::distance(__first2, __last2));
564 return __result;
565 }
566 }
567
568 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
569 typename _BinaryPredicate>
570 _BidirectionalIterator1
571 __find_end(_BidirectionalIterator1 __first1,
572 _BidirectionalIterator1 __last1,
573 _BidirectionalIterator2 __first2,
574 _BidirectionalIterator2 __last2,
575 bidirectional_iterator_tag, bidirectional_iterator_tag,
576 _BinaryPredicate __comp)
577 {
578 // concept requirements
579 __glibcxx_function_requires(_BidirectionalIteratorConcept<
580 _BidirectionalIterator1>)
581 __glibcxx_function_requires(_BidirectionalIteratorConcept<
582 _BidirectionalIterator2>)
583
584 typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1;
585 typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2;
586
587 _RevIterator1 __rlast1(__first1);
588 _RevIterator2 __rlast2(__first2);
589 _RevIterator1 __rresult = std::search(_RevIterator1(__last1), __rlast1,
590 _RevIterator2(__last2), __rlast2,
591 __comp);
592
593 if (__rresult == __rlast1)
594 return __last1;
595 else
596 {
597 _BidirectionalIterator1 __result = __rresult.base();
598 std::advance(__result, -std::distance(__first2, __last2));
599 return __result;
600 }
601 }
602
603 /**
604 * @brief Find last matching subsequence in a sequence.
605 * @param first1 Start of range to search.
606 * @param last1 End of range to search.
607 * @param first2 Start of sequence to match.
608 * @param last2 End of sequence to match.
609 * @return The last iterator @c i in the range
610 * @p [first1,last1-(last2-first2)) such that @c *(i+N) == @p *(first2+N)
611 * for each @c N in the range @p [0,last2-first2), or @p last1 if no
612 * such iterator exists.
613 *
614 * Searches the range @p [first1,last1) for a sub-sequence that compares
615 * equal value-by-value with the sequence given by @p [first2,last2) and
616 * returns an iterator to the first element of the sub-sequence, or
617 * @p last1 if the sub-sequence is not found. The sub-sequence will be the
618 * last such subsequence contained in [first,last1).
619 *
620 * Because the sub-sequence must lie completely within the range
621 * @p [first1,last1) it must start at a position less than
622 * @p last1-(last2-first2) where @p last2-first2 is the length of the
623 * sub-sequence.
624 * This means that the returned iterator @c i will be in the range
625 * @p [first1,last1-(last2-first2))
626 */
627 template<typename _ForwardIterator1, typename _ForwardIterator2>
628 inline _ForwardIterator1
629 find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
630 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
631 {
632 // concept requirements
633 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
634 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
635 __glibcxx_function_requires(_EqualOpConcept<
636 typename iterator_traits<_ForwardIterator1>::value_type,
637 typename iterator_traits<_ForwardIterator2>::value_type>)
638 __glibcxx_requires_valid_range(__first1, __last1);
639 __glibcxx_requires_valid_range(__first2, __last2);
640
641 return std::__find_end(__first1, __last1, __first2, __last2,
642 std::__iterator_category(__first1),
643 std::__iterator_category(__first2));
644 }
645
646 /**
647 * @brief Find last matching subsequence in a sequence using a predicate.
648 * @param first1 Start of range to search.
649 * @param last1 End of range to search.
650 * @param first2 Start of sequence to match.
651 * @param last2 End of sequence to match.
652 * @param comp The predicate to use.
653 * @return The last iterator @c i in the range
654 * @p [first1,last1-(last2-first2)) such that @c predicate(*(i+N), @p
655 * (first2+N)) is true for each @c N in the range @p [0,last2-first2), or
656 * @p last1 if no such iterator exists.
657 *
658 * Searches the range @p [first1,last1) for a sub-sequence that compares
659 * equal value-by-value with the sequence given by @p [first2,last2) using
660 * comp as a predicate and returns an iterator to the first element of the
661 * sub-sequence, or @p last1 if the sub-sequence is not found. The
662 * sub-sequence will be the last such subsequence contained in
663 * [first,last1).
664 *
665 * Because the sub-sequence must lie completely within the range
666 * @p [first1,last1) it must start at a position less than
667 * @p last1-(last2-first2) where @p last2-first2 is the length of the
668 * sub-sequence.
669 * This means that the returned iterator @c i will be in the range
670 * @p [first1,last1-(last2-first2))
671 */
672 template<typename _ForwardIterator1, typename _ForwardIterator2,
673 typename _BinaryPredicate>
674 inline _ForwardIterator1
675 find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
676 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
677 _BinaryPredicate __comp)
678 {
679 // concept requirements
680 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
681 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
682 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
683 typename iterator_traits<_ForwardIterator1>::value_type,
684 typename iterator_traits<_ForwardIterator2>::value_type>)
685 __glibcxx_requires_valid_range(__first1, __last1);
686 __glibcxx_requires_valid_range(__first2, __last2);
687
688 return std::__find_end(__first1, __last1, __first2, __last2,
689 std::__iterator_category(__first1),
690 std::__iterator_category(__first2),
691 __comp);
692 }
693
694
695 /**
696 * @brief Copy a sequence, removing elements of a given value.
697 * @param first An input iterator.
698 * @param last An input iterator.
699 * @param result An output iterator.
700 * @param value The value to be removed.
701 * @return An iterator designating the end of the resulting sequence.
702 *
703 * Copies each element in the range @p [first,last) not equal to @p value
704 * to the range beginning at @p result.
705 * remove_copy() is stable, so the relative order of elements that are
706 * copied is unchanged.
707 */
708 template<typename _InputIterator, typename _OutputIterator, typename _Tp>
709 _OutputIterator
710 remove_copy(_InputIterator __first, _InputIterator __last,
711 _OutputIterator __result, const _Tp& __value)
712 {
713 // concept requirements
714 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
715 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
716 typename iterator_traits<_InputIterator>::value_type>)
717 __glibcxx_function_requires(_EqualOpConcept<
718 typename iterator_traits<_InputIterator>::value_type, _Tp>)
719 __glibcxx_requires_valid_range(__first, __last);
720
721 for (; __first != __last; ++__first)
722 if (!(*__first == __value))
723 {
724 *__result = *__first;
725 ++__result;
726 }
727 return __result;
728 }
729
730 /**
731 * @brief Copy a sequence, removing elements for which a predicate is true.
732 * @param first An input iterator.
733 * @param last An input iterator.
734 * @param result An output iterator.
735 * @param pred A predicate.
736 * @return An iterator designating the end of the resulting sequence.
737 *
738 * Copies each element in the range @p [first,last) for which
739 * @p pred returns true to the range beginning at @p result.
740 *
741 * remove_copy_if() is stable, so the relative order of elements that are
742 * copied is unchanged.
743 */
744 template<typename _InputIterator, typename _OutputIterator,
745 typename _Predicate>
746 _OutputIterator
747 remove_copy_if(_InputIterator __first, _InputIterator __last,
748 _OutputIterator __result, _Predicate __pred)
749 {
750 // concept requirements
751 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
752 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
753 typename iterator_traits<_InputIterator>::value_type>)
754 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
755 typename iterator_traits<_InputIterator>::value_type>)
756 __glibcxx_requires_valid_range(__first, __last);
757
758 for (; __first != __last; ++__first)
759 if (!bool(__pred(*__first)))
760 {
761 *__result = *__first;
762 ++__result;
763 }
764 return __result;
765 }
766
767 /**
768 * @brief Remove elements from a sequence.
769 * @param first An input iterator.
770 * @param last An input iterator.
771 * @param value The value to be removed.
772 * @return An iterator designating the end of the resulting sequence.
773 *
774 * All elements equal to @p value are removed from the range
775 * @p [first,last).
776 *
777 * remove() is stable, so the relative order of elements that are
778 * not removed is unchanged.
779 *
780 * Elements between the end of the resulting sequence and @p last
781 * are still present, but their value is unspecified.
782 */
783 template<typename _ForwardIterator, typename _Tp>
784 _ForwardIterator
785 remove(_ForwardIterator __first, _ForwardIterator __last,
786 const _Tp& __value)
787 {
788 // concept requirements
789 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
790 _ForwardIterator>)
791 __glibcxx_function_requires(_EqualOpConcept<
792 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
793 __glibcxx_requires_valid_range(__first, __last);
794
795 __first = _GLIBCXX_STD_P::find(__first, __last, __value);
796 if(__first == __last)
797 return __first;
798 _ForwardIterator __result = __first;
799 ++__first;
800 for(; __first != __last; ++__first)
801 if(!(*__first == __value))
802 {
803 *__result = _GLIBCXX_MOVE(*__first);
804 ++__result;
805 }
806 return __result;
807 }
808
809 /**
810 * @brief Remove elements from a sequence using a predicate.
811 * @param first A forward iterator.
812 * @param last A forward iterator.
813 * @param pred A predicate.
814 * @return An iterator designating the end of the resulting sequence.
815 *
816 * All elements for which @p pred returns true are removed from the range
817 * @p [first,last).
818 *
819 * remove_if() is stable, so the relative order of elements that are
820 * not removed is unchanged.
821 *
822 * Elements between the end of the resulting sequence and @p last
823 * are still present, but their value is unspecified.
824 */
825 template<typename _ForwardIterator, typename _Predicate>
826 _ForwardIterator
827 remove_if(_ForwardIterator __first, _ForwardIterator __last,
828 _Predicate __pred)
829 {
830 // concept requirements
831 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
832 _ForwardIterator>)
833 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
834 typename iterator_traits<_ForwardIterator>::value_type>)
835 __glibcxx_requires_valid_range(__first, __last);
836
837 __first = _GLIBCXX_STD_P::find_if(__first, __last, __pred);
838 if(__first == __last)
839 return __first;
840 _ForwardIterator __result = __first;
841 ++__first;
842 for(; __first != __last; ++__first)
843 if(!__pred(*__first))
844 {
845 *__result = _GLIBCXX_MOVE(*__first);
846 ++__result;
847 }
848 return __result;
849 }
850
851 /**
852 * @brief Remove consecutive duplicate values from a sequence.
853 * @param first A forward iterator.
854 * @param last A forward iterator.
855 * @return An iterator designating the end of the resulting sequence.
856 *
857 * Removes all but the first element from each group of consecutive
858 * values that compare equal.
859 * unique() is stable, so the relative order of elements that are
860 * not removed is unchanged.
861 * Elements between the end of the resulting sequence and @p last
862 * are still present, but their value is unspecified.
863 */
864 template<typename _ForwardIterator>
865 _ForwardIterator
866 unique(_ForwardIterator __first, _ForwardIterator __last)
867 {
868 // concept requirements
869 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
870 _ForwardIterator>)
871 __glibcxx_function_requires(_EqualityComparableConcept<
872 typename iterator_traits<_ForwardIterator>::value_type>)
873 __glibcxx_requires_valid_range(__first, __last);
874
875 // Skip the beginning, if already unique.
876 __first = _GLIBCXX_STD_P::adjacent_find(__first, __last);
877 if (__first == __last)
878 return __last;
879
880 // Do the real copy work.
881 _ForwardIterator __dest = __first;
882 ++__first;
883 while (++__first != __last)
884 if (!(*__dest == *__first))
885 *++__dest = _GLIBCXX_MOVE(*__first);
886 return ++__dest;
887 }
888
889 /**
890 * @brief Remove consecutive values from a sequence using a predicate.
891 * @param first A forward iterator.
892 * @param last A forward iterator.
893 * @param binary_pred A binary predicate.
894 * @return An iterator designating the end of the resulting sequence.
895 *
896 * Removes all but the first element from each group of consecutive
897 * values for which @p binary_pred returns true.
898 * unique() is stable, so the relative order of elements that are
899 * not removed is unchanged.
900 * Elements between the end of the resulting sequence and @p last
901 * are still present, but their value is unspecified.
902 */
903 template<typename _ForwardIterator, typename _BinaryPredicate>
904 _ForwardIterator
905 unique(_ForwardIterator __first, _ForwardIterator __last,
906 _BinaryPredicate __binary_pred)
907 {
908 // concept requirements
909 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
910 _ForwardIterator>)
911 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
912 typename iterator_traits<_ForwardIterator>::value_type,
913 typename iterator_traits<_ForwardIterator>::value_type>)
914 __glibcxx_requires_valid_range(__first, __last);
915
916 // Skip the beginning, if already unique.
917 __first = _GLIBCXX_STD_P::adjacent_find(__first, __last, __binary_pred);
918 if (__first == __last)
919 return __last;
920
921 // Do the real copy work.
922 _ForwardIterator __dest = __first;
923 ++__first;
924 while (++__first != __last)
925 if (!bool(__binary_pred(*__dest, *__first)))
926 *++__dest = _GLIBCXX_MOVE(*__first);
927 return ++__dest;
928 }
929
930 /**
931 * @if maint
932 * This is an uglified unique_copy(_InputIterator, _InputIterator,
933 * _OutputIterator)
934 * overloaded for forward iterators and output iterator as result.
935 * @endif
936 */
937 template<typename _ForwardIterator, typename _OutputIterator>
938 _OutputIterator
939 __unique_copy(_ForwardIterator __first, _ForwardIterator __last,
940 _OutputIterator __result,
941 forward_iterator_tag, output_iterator_tag)
942 {
943 // concept requirements -- taken care of in dispatching function
944 _ForwardIterator __next = __first;
945 *__result = *__first;
946 while (++__next != __last)
947 if (!(*__first == *__next))
948 {
949 __first = __next;
950 *++__result = *__first;
951 }
952 return ++__result;
953 }
954
955 /**
956 * @if maint
957 * This is an uglified unique_copy(_InputIterator, _InputIterator,
958 * _OutputIterator)
959 * overloaded for input iterators and output iterator as result.
960 * @endif
961 */
962 template<typename _InputIterator, typename _OutputIterator>
963 _OutputIterator
964 __unique_copy(_InputIterator __first, _InputIterator __last,
965 _OutputIterator __result,
966 input_iterator_tag, output_iterator_tag)
967 {
968 // concept requirements -- taken care of in dispatching function
969 typename iterator_traits<_InputIterator>::value_type __value = *__first;
970 *__result = __value;
971 while (++__first != __last)
972 if (!(__value == *__first))
973 {
974 __value = *__first;
975 *++__result = __value;
976 }
977 return ++__result;
978 }
979
980 /**
981 * @if maint
982 * This is an uglified unique_copy(_InputIterator, _InputIterator,
983 * _OutputIterator)
984 * overloaded for input iterators and forward iterator as result.
985 * @endif
986 */
987 template<typename _InputIterator, typename _ForwardIterator>
988 _ForwardIterator
989 __unique_copy(_InputIterator __first, _InputIterator __last,
990 _ForwardIterator __result,
991 input_iterator_tag, forward_iterator_tag)
992 {
993 // concept requirements -- taken care of in dispatching function
994 *__result = *__first;
995 while (++__first != __last)
996 if (!(*__result == *__first))
997 *++__result = *__first;
998 return ++__result;
999 }
1000
1001 /**
1002 * @if maint
1003 * This is an uglified
1004 * unique_copy(_InputIterator, _InputIterator, _OutputIterator,
1005 * _BinaryPredicate)
1006 * overloaded for forward iterators and output iterator as result.
1007 * @endif
1008 */
1009 template<typename _ForwardIterator, typename _OutputIterator,
1010 typename _BinaryPredicate>
1011 _OutputIterator
1012 __unique_copy(_ForwardIterator __first, _ForwardIterator __last,
1013 _OutputIterator __result, _BinaryPredicate __binary_pred,
1014 forward_iterator_tag, output_iterator_tag)
1015 {
1016 // concept requirements -- iterators already checked
1017 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1018 typename iterator_traits<_ForwardIterator>::value_type,
1019 typename iterator_traits<_ForwardIterator>::value_type>)
1020
1021 _ForwardIterator __next = __first;
1022 *__result = *__first;
1023 while (++__next != __last)
1024 if (!bool(__binary_pred(*__first, *__next)))
1025 {
1026 __first = __next;
1027 *++__result = *__first;
1028 }
1029 return ++__result;
1030 }
1031
1032 /**
1033 * @if maint
1034 * This is an uglified
1035 * unique_copy(_InputIterator, _InputIterator, _OutputIterator,
1036 * _BinaryPredicate)
1037 * overloaded for input iterators and output iterator as result.
1038 * @endif
1039 */
1040 template<typename _InputIterator, typename _OutputIterator,
1041 typename _BinaryPredicate>
1042 _OutputIterator
1043 __unique_copy(_InputIterator __first, _InputIterator __last,
1044 _OutputIterator __result, _BinaryPredicate __binary_pred,
1045 input_iterator_tag, output_iterator_tag)
1046 {
1047 // concept requirements -- iterators already checked
1048 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1049 typename iterator_traits<_InputIterator>::value_type,
1050 typename iterator_traits<_InputIterator>::value_type>)
1051
1052 typename iterator_traits<_InputIterator>::value_type __value = *__first;
1053 *__result = __value;
1054 while (++__first != __last)
1055 if (!bool(__binary_pred(__value, *__first)))
1056 {
1057 __value = *__first;
1058 *++__result = __value;
1059 }
1060 return ++__result;
1061 }
1062
1063 /**
1064 * @if maint
1065 * This is an uglified
1066 * unique_copy(_InputIterator, _InputIterator, _OutputIterator,
1067 * _BinaryPredicate)
1068 * overloaded for input iterators and forward iterator as result.
1069 * @endif
1070 */
1071 template<typename _InputIterator, typename _ForwardIterator,
1072 typename _BinaryPredicate>
1073 _ForwardIterator
1074 __unique_copy(_InputIterator __first, _InputIterator __last,
1075 _ForwardIterator __result, _BinaryPredicate __binary_pred,
1076 input_iterator_tag, forward_iterator_tag)
1077 {
1078 // concept requirements -- iterators already checked
1079 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
1080 typename iterator_traits<_ForwardIterator>::value_type,
1081 typename iterator_traits<_InputIterator>::value_type>)
1082
1083 *__result = *__first;
1084 while (++__first != __last)
1085 if (!bool(__binary_pred(*__result, *__first)))
1086 *++__result = *__first;
1087 return ++__result;
1088 }
1089
1090 /**
1091 * @if maint
1092 * This is an uglified reverse(_BidirectionalIterator,
1093 * _BidirectionalIterator)
1094 * overloaded for bidirectional iterators.
1095 * @endif
1096 */
1097 template<typename _BidirectionalIterator>
1098 void
1099 __reverse(_BidirectionalIterator __first, _BidirectionalIterator __last,
1100 bidirectional_iterator_tag)
1101 {
1102 while (true)
1103 if (__first == __last || __first == --__last)
1104 return;
1105 else
1106 {
1107 std::iter_swap(__first, __last);
1108 ++__first;
1109 }
1110 }
1111
1112 /**
1113 * @if maint
1114 * This is an uglified reverse(_BidirectionalIterator,
1115 * _BidirectionalIterator)
1116 * overloaded for random access iterators.
1117 * @endif
1118 */
1119 template<typename _RandomAccessIterator>
1120 void
1121 __reverse(_RandomAccessIterator __first, _RandomAccessIterator __last,
1122 random_access_iterator_tag)
1123 {
1124 if (__first == __last)
1125 return;
1126 --__last;
1127 while (__first < __last)
1128 {
1129 std::iter_swap(__first, __last);
1130 ++__first;
1131 --__last;
1132 }
1133 }
1134
1135 /**
1136 * @brief Reverse a sequence.
1137 * @param first A bidirectional iterator.
1138 * @param last A bidirectional iterator.
1139 * @return reverse() returns no value.
1140 *
1141 * Reverses the order of the elements in the range @p [first,last),
1142 * so that the first element becomes the last etc.
1143 * For every @c i such that @p 0<=i<=(last-first)/2), @p reverse()
1144 * swaps @p *(first+i) and @p *(last-(i+1))
1145 */
1146 template<typename _BidirectionalIterator>
1147 inline void
1148 reverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
1149 {
1150 // concept requirements
1151 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
1152 _BidirectionalIterator>)
1153 __glibcxx_requires_valid_range(__first, __last);
1154 std::__reverse(__first, __last, std::__iterator_category(__first));
1155 }
1156
1157 /**
1158 * @brief Copy a sequence, reversing its elements.
1159 * @param first A bidirectional iterator.
1160 * @param last A bidirectional iterator.
1161 * @param result An output iterator.
1162 * @return An iterator designating the end of the resulting sequence.
1163 *
1164 * Copies the elements in the range @p [first,last) to the range
1165 * @p [result,result+(last-first)) such that the order of the
1166 * elements is reversed.
1167 * For every @c i such that @p 0<=i<=(last-first), @p reverse_copy()
1168 * performs the assignment @p *(result+(last-first)-i) = *(first+i).
1169 * The ranges @p [first,last) and @p [result,result+(last-first))
1170 * must not overlap.
1171 */
1172 template<typename _BidirectionalIterator, typename _OutputIterator>
1173 _OutputIterator
1174 reverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last,
1175 _OutputIterator __result)
1176 {
1177 // concept requirements
1178 __glibcxx_function_requires(_BidirectionalIteratorConcept<
1179 _BidirectionalIterator>)
1180 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
1181 typename iterator_traits<_BidirectionalIterator>::value_type>)
1182 __glibcxx_requires_valid_range(__first, __last);
1183
1184 while (__first != __last)
1185 {
1186 --__last;
1187 *__result = *__last;
1188 ++__result;
1189 }
1190 return __result;
1191 }
1192
1193 /**
1194 * @if maint
1195 * This is a helper function for the rotate algorithm specialized on RAIs.
1196 * It returns the greatest common divisor of two integer values.
1197 * @endif
1198 */
1199 template<typename _EuclideanRingElement>
1200 _EuclideanRingElement
1201 __gcd(_EuclideanRingElement __m, _EuclideanRingElement __n)
1202 {
1203 while (__n != 0)
1204 {
1205 _EuclideanRingElement __t = __m % __n;
1206 __m = __n;
1207 __n = __t;
1208 }
1209 return __m;
1210 }
1211
1212 /**
1213 * @if maint
1214 * This is a helper function for the rotate algorithm.
1215 * @endif
1216 */
1217 template<typename _ForwardIterator>
1218 void
1219 __rotate(_ForwardIterator __first,
1220 _ForwardIterator __middle,
1221 _ForwardIterator __last,
1222 forward_iterator_tag)
1223 {
1224 if (__first == __middle || __last == __middle)
1225 return;
1226
1227 _ForwardIterator __first2 = __middle;
1228 do
1229 {
1230 std::iter_swap(__first, __first2);
1231 ++__first;
1232 ++__first2;
1233 if (__first == __middle)
1234 __middle = __first2;
1235 }
1236 while (__first2 != __last);
1237
1238 __first2 = __middle;
1239
1240 while (__first2 != __last)
1241 {
1242 std::iter_swap(__first, __first2);
1243 ++__first;
1244 ++__first2;
1245 if (__first == __middle)
1246 __middle = __first2;
1247 else if (__first2 == __last)
1248 __first2 = __middle;
1249 }
1250 }
1251
1252 /**
1253 * @if maint
1254 * This is a helper function for the rotate algorithm.
1255 * @endif
1256 */
1257 template<typename _BidirectionalIterator>
1258 void
1259 __rotate(_BidirectionalIterator __first,
1260 _BidirectionalIterator __middle,
1261 _BidirectionalIterator __last,
1262 bidirectional_iterator_tag)
1263 {
1264 // concept requirements
1265 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
1266 _BidirectionalIterator>)
1267
1268 if (__first == __middle || __last == __middle)
1269 return;
1270
1271 std::__reverse(__first, __middle, bidirectional_iterator_tag());
1272 std::__reverse(__middle, __last, bidirectional_iterator_tag());
1273
1274 while (__first != __middle && __middle != __last)
1275 {
1276 std::iter_swap(__first, --__last);
1277 ++__first;
1278 }
1279
1280 if (__first == __middle)
1281 std::__reverse(__middle, __last, bidirectional_iterator_tag());
1282 else
1283 std::__reverse(__first, __middle, bidirectional_iterator_tag());
1284 }
1285
1286 /**
1287 * @if maint
1288 * This is a helper function for the rotate algorithm.
1289 * @endif
1290 */
1291 template<typename _RandomAccessIterator>
1292 void
1293 __rotate(_RandomAccessIterator __first,
1294 _RandomAccessIterator __middle,
1295 _RandomAccessIterator __last,
1296 random_access_iterator_tag)
1297 {
1298 // concept requirements
1299 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
1300 _RandomAccessIterator>)
1301
1302 if (__first == __middle || __last == __middle)
1303 return;
1304
1305 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
1306 _Distance;
1307 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1308 _ValueType;
1309
1310 const _Distance __n = __last - __first;
1311 const _Distance __k = __middle - __first;
1312 const _Distance __l = __n - __k;
1313
1314 if (__k == __l)
1315 {
1316 std::swap_ranges(__first, __middle, __middle);
1317 return;
1318 }
1319
1320 const _Distance __d = std::__gcd(__n, __k);
1321
1322 for (_Distance __i = 0; __i < __d; __i++)
1323 {
1324 _ValueType __tmp = _GLIBCXX_MOVE(*__first);
1325 _RandomAccessIterator __p = __first;
1326
1327 if (__k < __l)
1328 {
1329 for (_Distance __j = 0; __j < __l / __d; __j++)
1330 {
1331 if (__p > __first + __l)
1332 {
1333 *__p = _GLIBCXX_MOVE(*(__p - __l));
1334 __p -= __l;
1335 }
1336
1337 *__p = _GLIBCXX_MOVE(*(__p + __k));
1338 __p += __k;
1339 }
1340 }
1341 else
1342 {
1343 for (_Distance __j = 0; __j < __k / __d - 1; __j ++)
1344 {
1345 if (__p < __last - __k)
1346 {
1347 *__p = _GLIBCXX_MOVE(*(__p + __k));
1348 __p += __k;
1349 }
1350 *__p = _GLIBCXX_MOVE(*(__p - __l));
1351 __p -= __l;
1352 }
1353 }
1354
1355 *__p = _GLIBCXX_MOVE(__tmp);
1356 ++__first;
1357 }
1358 }
1359
1360 /**
1361 * @brief Rotate the elements of a sequence.
1362 * @param first A forward iterator.
1363 * @param middle A forward iterator.
1364 * @param last A forward iterator.
1365 * @return Nothing.
1366 *
1367 * Rotates the elements of the range @p [first,last) by @p (middle-first)
1368 * positions so that the element at @p middle is moved to @p first, the
1369 * element at @p middle+1 is moved to @first+1 and so on for each element
1370 * in the range @p [first,last).
1371 *
1372 * This effectively swaps the ranges @p [first,middle) and
1373 * @p [middle,last).
1374 *
1375 * Performs @p *(first+(n+(last-middle))%(last-first))=*(first+n) for
1376 * each @p n in the range @p [0,last-first).
1377 */
1378 template<typename _ForwardIterator>
1379 inline void
1380 rotate(_ForwardIterator __first, _ForwardIterator __middle,
1381 _ForwardIterator __last)
1382 {
1383 // concept requirements
1384 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
1385 _ForwardIterator>)
1386 __glibcxx_requires_valid_range(__first, __middle);
1387 __glibcxx_requires_valid_range(__middle, __last);
1388
1389 typedef typename iterator_traits<_ForwardIterator>::iterator_category
1390 _IterType;
1391 std::__rotate(__first, __middle, __last, _IterType());
1392 }
1393
1394 /**
1395 * @brief Copy a sequence, rotating its elements.
1396 * @param first A forward iterator.
1397 * @param middle A forward iterator.
1398 * @param last A forward iterator.
1399 * @param result An output iterator.
1400 * @return An iterator designating the end of the resulting sequence.
1401 *
1402 * Copies the elements of the range @p [first,last) to the range
1403 * beginning at @result, rotating the copied elements by @p (middle-first)
1404 * positions so that the element at @p middle is moved to @p result, the
1405 * element at @p middle+1 is moved to @result+1 and so on for each element
1406 * in the range @p [first,last).
1407 *
1408 * Performs @p *(result+(n+(last-middle))%(last-first))=*(first+n) for
1409 * each @p n in the range @p [0,last-first).
1410 */
1411 template<typename _ForwardIterator, typename _OutputIterator>
1412 _OutputIterator
1413 rotate_copy(_ForwardIterator __first, _ForwardIterator __middle,
1414 _ForwardIterator __last, _OutputIterator __result)
1415 {
1416 // concept requirements
1417 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
1418 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
1419 typename iterator_traits<_ForwardIterator>::value_type>)
1420 __glibcxx_requires_valid_range(__first, __middle);
1421 __glibcxx_requires_valid_range(__middle, __last);
1422
1423 return std::copy(__first, __middle,
1424 std::copy(__middle, __last, __result));
1425 }
1426
1427 /**
1428 * @if maint
1429 * This is a helper function...
1430 * @endif
1431 */
1432 template<typename _ForwardIterator, typename _Predicate>
1433 _ForwardIterator
1434 __partition(_ForwardIterator __first, _ForwardIterator __last,
1435 _Predicate __pred, forward_iterator_tag)
1436 {
1437 if (__first == __last)
1438 return __first;
1439
1440 while (__pred(*__first))
1441 if (++__first == __last)
1442 return __first;
1443
1444 _ForwardIterator __next = __first;
1445
1446 while (++__next != __last)
1447 if (__pred(*__next))
1448 {
1449 std::iter_swap(__first, __next);
1450 ++__first;
1451 }
1452
1453 return __first;
1454 }
1455
1456 /**
1457 * @if maint
1458 * This is a helper function...
1459 * @endif
1460 */
1461 template<typename _BidirectionalIterator, typename _Predicate>
1462 _BidirectionalIterator
1463 __partition(_BidirectionalIterator __first, _BidirectionalIterator __last,
1464 _Predicate __pred, bidirectional_iterator_tag)
1465 {
1466 while (true)
1467 {
1468 while (true)
1469 if (__first == __last)
1470 return __first;
1471 else if (__pred(*__first))
1472 ++__first;
1473 else
1474 break;
1475 --__last;
1476 while (true)
1477 if (__first == __last)
1478 return __first;
1479 else if (!bool(__pred(*__last)))
1480 --__last;
1481 else
1482 break;
1483 std::iter_swap(__first, __last);
1484 ++__first;
1485 }
1486 }
1487
1488 // partition
1489
1490 /**
1491 * @if maint
1492 * This is a helper function...
1493 * @endif
1494 */
1495 template<typename _ForwardIterator, typename _Predicate, typename _Distance>
1496 _ForwardIterator
1497 __inplace_stable_partition(_ForwardIterator __first,
1498 _ForwardIterator __last,
1499 _Predicate __pred, _Distance __len)
1500 {
1501 if (__len == 1)
1502 return __pred(*__first) ? __last : __first;
1503 _ForwardIterator __middle = __first;
1504 std::advance(__middle, __len / 2);
1505 _ForwardIterator __begin = std::__inplace_stable_partition(__first,
1506 __middle,
1507 __pred,
1508 __len / 2);
1509 _ForwardIterator __end = std::__inplace_stable_partition(__middle, __last,
1510 __pred,
1511 __len
1512 - __len / 2);
1513 std::rotate(__begin, __middle, __end);
1514 std::advance(__begin, std::distance(__middle, __end));
1515 return __begin;
1516 }
1517
1518 /**
1519 * @if maint
1520 * This is a helper function...
1521 * @endif
1522 */
1523 template<typename _ForwardIterator, typename _Pointer, typename _Predicate,
1524 typename _Distance>
1525 _ForwardIterator
1526 __stable_partition_adaptive(_ForwardIterator __first,
1527 _ForwardIterator __last,
1528 _Predicate __pred, _Distance __len,
1529 _Pointer __buffer,
1530 _Distance __buffer_size)
1531 {
1532 if (__len <= __buffer_size)
1533 {
1534 _ForwardIterator __result1 = __first;
1535 _Pointer __result2 = __buffer;
1536 for (; __first != __last; ++__first)
1537 if (__pred(*__first))
1538 {
1539 *__result1 = *__first;
1540 ++__result1;
1541 }
1542 else
1543 {
1544 *__result2 = *__first;
1545 ++__result2;
1546 }
1547 std::copy(__buffer, __result2, __result1);
1548 return __result1;
1549 }
1550 else
1551 {
1552 _ForwardIterator __middle = __first;
1553 std::advance(__middle, __len / 2);
1554 _ForwardIterator __begin =
1555 std::__stable_partition_adaptive(__first, __middle, __pred,
1556 __len / 2, __buffer,
1557 __buffer_size);
1558 _ForwardIterator __end =
1559 std::__stable_partition_adaptive(__middle, __last, __pred,
1560 __len - __len / 2,
1561 __buffer, __buffer_size);
1562 std::rotate(__begin, __middle, __end);
1563 std::advance(__begin, std::distance(__middle, __end));
1564 return __begin;
1565 }
1566 }
1567
1568 /**
1569 * @brief Move elements for which a predicate is true to the beginning
1570 * of a sequence, preserving relative ordering.
1571 * @param first A forward iterator.
1572 * @param last A forward iterator.
1573 * @param pred A predicate functor.
1574 * @return An iterator @p middle such that @p pred(i) is true for each
1575 * iterator @p i in the range @p [first,middle) and false for each @p i
1576 * in the range @p [middle,last).
1577 *
1578 * Performs the same function as @p partition() with the additional
1579 * guarantee that the relative ordering of elements in each group is
1580 * preserved, so any two elements @p x and @p y in the range
1581 * @p [first,last) such that @p pred(x)==pred(y) will have the same
1582 * relative ordering after calling @p stable_partition().
1583 */
1584 template<typename _ForwardIterator, typename _Predicate>
1585 _ForwardIterator
1586 stable_partition(_ForwardIterator __first, _ForwardIterator __last,
1587 _Predicate __pred)
1588 {
1589 // concept requirements
1590 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
1591 _ForwardIterator>)
1592 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
1593 typename iterator_traits<_ForwardIterator>::value_type>)
1594 __glibcxx_requires_valid_range(__first, __last);
1595
1596 if (__first == __last)
1597 return __first;
1598 else
1599 {
1600 typedef typename iterator_traits<_ForwardIterator>::value_type
1601 _ValueType;
1602 typedef typename iterator_traits<_ForwardIterator>::difference_type
1603 _DistanceType;
1604
1605 _Temporary_buffer<_ForwardIterator, _ValueType> __buf(__first,
1606 __last);
1607 if (__buf.size() > 0)
1608 return
1609 std::__stable_partition_adaptive(__first, __last, __pred,
1610 _DistanceType(__buf.requested_size()),
1611 __buf.begin(),
1612 _DistanceType(__buf.size()));
1613 else
1614 return
1615 std::__inplace_stable_partition(__first, __last, __pred,
1616 _DistanceType(__buf.requested_size()));
1617 }
1618 }
1619
1620 /**
1621 * @if maint
1622 * This is a helper function for the sort routines.
1623 * @endif
1624 */
1625 template<typename _RandomAccessIterator>
1626 void
1627 __heap_select(_RandomAccessIterator __first,
1628 _RandomAccessIterator __middle,
1629 _RandomAccessIterator __last)
1630 {
1631 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1632 _ValueType;
1633
1634 std::make_heap(__first, __middle);
1635 for (_RandomAccessIterator __i = __middle; __i < __last; ++__i)
1636 if (*__i < *__first)
1637 std::__pop_heap(__first, __middle, __i, _ValueType(*__i));
1638 }
1639
1640 /**
1641 * @if maint
1642 * This is a helper function for the sort routines.
1643 * @endif
1644 */
1645 template<typename _RandomAccessIterator, typename _Compare>
1646 void
1647 __heap_select(_RandomAccessIterator __first,
1648 _RandomAccessIterator __middle,
1649 _RandomAccessIterator __last, _Compare __comp)
1650 {
1651 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1652 _ValueType;
1653
1654 std::make_heap(__first, __middle, __comp);
1655 for (_RandomAccessIterator __i = __middle; __i < __last; ++__i)
1656 if (__comp(*__i, *__first))
1657 std::__pop_heap(__first, __middle, __i, _ValueType(*__i), __comp);
1658 }
1659
1660 // partial_sort
1661
1662 /**
1663 * @brief Copy the smallest elements of a sequence.
1664 * @param first An iterator.
1665 * @param last Another iterator.
1666 * @param result_first A random-access iterator.
1667 * @param result_last Another random-access iterator.
1668 * @return An iterator indicating the end of the resulting sequence.
1669 *
1670 * Copies and sorts the smallest N values from the range @p [first,last)
1671 * to the range beginning at @p result_first, where the number of
1672 * elements to be copied, @p N, is the smaller of @p (last-first) and
1673 * @p (result_last-result_first).
1674 * After the sort if @p i and @j are iterators in the range
1675 * @p [result_first,result_first+N) such that @i precedes @j then
1676 * @p *j<*i is false.
1677 * The value returned is @p result_first+N.
1678 */
1679 template<typename _InputIterator, typename _RandomAccessIterator>
1680 _RandomAccessIterator
1681 partial_sort_copy(_InputIterator __first, _InputIterator __last,
1682 _RandomAccessIterator __result_first,
1683 _RandomAccessIterator __result_last)
1684 {
1685 typedef typename iterator_traits<_InputIterator>::value_type
1686 _InputValueType;
1687 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1688 _OutputValueType;
1689 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
1690 _DistanceType;
1691
1692 // concept requirements
1693 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
1694 __glibcxx_function_requires(_ConvertibleConcept<_InputValueType,
1695 _OutputValueType>)
1696 __glibcxx_function_requires(_LessThanOpConcept<_InputValueType,
1697 _OutputValueType>)
1698 __glibcxx_function_requires(_LessThanComparableConcept<_OutputValueType>)
1699 __glibcxx_requires_valid_range(__first, __last);
1700 __glibcxx_requires_valid_range(__result_first, __result_last);
1701
1702 if (__result_first == __result_last)
1703 return __result_last;
1704 _RandomAccessIterator __result_real_last = __result_first;
1705 while(__first != __last && __result_real_last != __result_last)
1706 {
1707 *__result_real_last = *__first;
1708 ++__result_real_last;
1709 ++__first;
1710 }
1711 std::make_heap(__result_first, __result_real_last);
1712 while (__first != __last)
1713 {
1714 if (*__first < *__result_first)
1715 std::__adjust_heap(__result_first, _DistanceType(0),
1716 _DistanceType(__result_real_last
1717 - __result_first),
1718 _InputValueType(*__first));
1719 ++__first;
1720 }
1721 std::sort_heap(__result_first, __result_real_last);
1722 return __result_real_last;
1723 }
1724
1725 /**
1726 * @brief Copy the smallest elements of a sequence using a predicate for
1727 * comparison.
1728 * @param first An input iterator.
1729 * @param last Another input iterator.
1730 * @param result_first A random-access iterator.
1731 * @param result_last Another random-access iterator.
1732 * @param comp A comparison functor.
1733 * @return An iterator indicating the end of the resulting sequence.
1734 *
1735 * Copies and sorts the smallest N values from the range @p [first,last)
1736 * to the range beginning at @p result_first, where the number of
1737 * elements to be copied, @p N, is the smaller of @p (last-first) and
1738 * @p (result_last-result_first).
1739 * After the sort if @p i and @j are iterators in the range
1740 * @p [result_first,result_first+N) such that @i precedes @j then
1741 * @p comp(*j,*i) is false.
1742 * The value returned is @p result_first+N.
1743 */
1744 template<typename _InputIterator, typename _RandomAccessIterator, typename _Compare>
1745 _RandomAccessIterator
1746 partial_sort_copy(_InputIterator __first, _InputIterator __last,
1747 _RandomAccessIterator __result_first,
1748 _RandomAccessIterator __result_last,
1749 _Compare __comp)
1750 {
1751 typedef typename iterator_traits<_InputIterator>::value_type
1752 _InputValueType;
1753 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1754 _OutputValueType;
1755 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
1756 _DistanceType;
1757
1758 // concept requirements
1759 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
1760 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
1761 _RandomAccessIterator>)
1762 __glibcxx_function_requires(_ConvertibleConcept<_InputValueType,
1763 _OutputValueType>)
1764 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
1765 _InputValueType, _OutputValueType>)
1766 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
1767 _OutputValueType, _OutputValueType>)
1768 __glibcxx_requires_valid_range(__first, __last);
1769 __glibcxx_requires_valid_range(__result_first, __result_last);
1770
1771 if (__result_first == __result_last)
1772 return __result_last;
1773 _RandomAccessIterator __result_real_last = __result_first;
1774 while(__first != __last && __result_real_last != __result_last)
1775 {
1776 *__result_real_last = *__first;
1777 ++__result_real_last;
1778 ++__first;
1779 }
1780 std::make_heap(__result_first, __result_real_last, __comp);
1781 while (__first != __last)
1782 {
1783 if (__comp(*__first, *__result_first))
1784 std::__adjust_heap(__result_first, _DistanceType(0),
1785 _DistanceType(__result_real_last
1786 - __result_first),
1787 _InputValueType(*__first),
1788 __comp);
1789 ++__first;
1790 }
1791 std::sort_heap(__result_first, __result_real_last, __comp);
1792 return __result_real_last;
1793 }
1794
1795 /**
1796 * @if maint
1797 * This is a helper function for the sort routine.
1798 * @endif
1799 */
1800 template<typename _RandomAccessIterator, typename _Tp>
1801 void
1802 __unguarded_linear_insert(_RandomAccessIterator __last, _Tp __val)
1803 {
1804 _RandomAccessIterator __next = __last;
1805 --__next;
1806 while (__val < *__next)
1807 {
1808 *__last = *__next;
1809 __last = __next;
1810 --__next;
1811 }
1812 *__last = __val;
1813 }
1814
1815 /**
1816 * @if maint
1817 * This is a helper function for the sort routine.
1818 * @endif
1819 */
1820 template<typename _RandomAccessIterator, typename _Tp, typename _Compare>
1821 void
1822 __unguarded_linear_insert(_RandomAccessIterator __last, _Tp __val,
1823 _Compare __comp)
1824 {
1825 _RandomAccessIterator __next = __last;
1826 --__next;
1827 while (__comp(__val, *__next))
1828 {
1829 *__last = *__next;
1830 __last = __next;
1831 --__next;
1832 }
1833 *__last = __val;
1834 }
1835
1836 /**
1837 * @if maint
1838 * This is a helper function for the sort routine.
1839 * @endif
1840 */
1841 template<typename _RandomAccessIterator>
1842 void
1843 __insertion_sort(_RandomAccessIterator __first,
1844 _RandomAccessIterator __last)
1845 {
1846 if (__first == __last)
1847 return;
1848
1849 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
1850 {
1851 typename iterator_traits<_RandomAccessIterator>::value_type
1852 __val = *__i;
1853 if (__val < *__first)
1854 {
1855 std::copy_backward(__first, __i, __i + 1);
1856 *__first = __val;
1857 }
1858 else
1859 std::__unguarded_linear_insert(__i, __val);
1860 }
1861 }
1862
1863 /**
1864 * @if maint
1865 * This is a helper function for the sort routine.
1866 * @endif
1867 */
1868 template<typename _RandomAccessIterator, typename _Compare>
1869 void
1870 __insertion_sort(_RandomAccessIterator __first,
1871 _RandomAccessIterator __last, _Compare __comp)
1872 {
1873 if (__first == __last) return;
1874
1875 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
1876 {
1877 typename iterator_traits<_RandomAccessIterator>::value_type
1878 __val = *__i;
1879 if (__comp(__val, *__first))
1880 {
1881 std::copy_backward(__first, __i, __i + 1);
1882 *__first = __val;
1883 }
1884 else
1885 std::__unguarded_linear_insert(__i, __val, __comp);
1886 }
1887 }
1888
1889 /**
1890 * @if maint
1891 * This is a helper function for the sort routine.
1892 * @endif
1893 */
1894 template<typename _RandomAccessIterator>
1895 inline void
1896 __unguarded_insertion_sort(_RandomAccessIterator __first,
1897 _RandomAccessIterator __last)
1898 {
1899 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1900 _ValueType;
1901
1902 for (_RandomAccessIterator __i = __first; __i != __last; ++__i)
1903 std::__unguarded_linear_insert(__i, _ValueType(*__i));
1904 }
1905
1906 /**
1907 * @if maint
1908 * This is a helper function for the sort routine.
1909 * @endif
1910 */
1911 template<typename _RandomAccessIterator, typename _Compare>
1912 inline void
1913 __unguarded_insertion_sort(_RandomAccessIterator __first,
1914 _RandomAccessIterator __last, _Compare __comp)
1915 {
1916 typedef typename iterator_traits<_RandomAccessIterator>::value_type
1917 _ValueType;
1918
1919 for (_RandomAccessIterator __i = __first; __i != __last; ++__i)
1920 std::__unguarded_linear_insert(__i, _ValueType(*__i), __comp);
1921 }
1922
1923 /**
1924 * @if maint
1925 * @doctodo
1926 * This controls some aspect of the sort routines.
1927 * @endif
1928 */
1929 enum { _S_threshold = 16 };
1930
1931 /**
1932 * @if maint
1933 * This is a helper function for the sort routine.
1934 * @endif
1935 */
1936 template<typename _RandomAccessIterator>
1937 void
1938 __final_insertion_sort(_RandomAccessIterator __first,
1939 _RandomAccessIterator __last)
1940 {
1941 if (__last - __first > int(_S_threshold))
1942 {
1943 std::__insertion_sort(__first, __first + int(_S_threshold));
1944 std::__unguarded_insertion_sort(__first + int(_S_threshold), __last);
1945 }
1946 else
1947 std::__insertion_sort(__first, __last);
1948 }
1949
1950 /**
1951 * @if maint
1952 * This is a helper function for the sort routine.
1953 * @endif
1954 */
1955 template<typename _RandomAccessIterator, typename _Compare>
1956 void
1957 __final_insertion_sort(_RandomAccessIterator __first,
1958 _RandomAccessIterator __last, _Compare __comp)
1959 {
1960 if (__last - __first > int(_S_threshold))
1961 {
1962 std::__insertion_sort(__first, __first + int(_S_threshold), __comp);
1963 std::__unguarded_insertion_sort(__first + int(_S_threshold), __last,
1964 __comp);
1965 }
1966 else
1967 std::__insertion_sort(__first, __last, __comp);
1968 }
1969
1970 /**
1971 * @if maint
1972 * This is a helper function...
1973 * @endif
1974 */
1975 template<typename _RandomAccessIterator, typename _Tp>
1976 _RandomAccessIterator
1977 __unguarded_partition(_RandomAccessIterator __first,
1978 _RandomAccessIterator __last, _Tp __pivot)
1979 {
1980 while (true)
1981 {
1982 while (*__first < __pivot)
1983 ++__first;
1984 --__last;
1985 while (__pivot < *__last)
1986 --__last;
1987 if (!(__first < __last))
1988 return __first;
1989 std::iter_swap(__first, __last);
1990 ++__first;
1991 }
1992 }
1993
1994 /**
1995 * @if maint
1996 * This is a helper function...
1997 * @endif
1998 */
1999 template<typename _RandomAccessIterator, typename _Tp, typename _Compare>
2000 _RandomAccessIterator
2001 __unguarded_partition(_RandomAccessIterator __first,
2002 _RandomAccessIterator __last,
2003 _Tp __pivot, _Compare __comp)
2004 {
2005 while (true)
2006 {
2007 while (__comp(*__first, __pivot))
2008 ++__first;
2009 --__last;
2010 while (__comp(__pivot, *__last))
2011 --__last;
2012 if (!(__first < __last))
2013 return __first;
2014 std::iter_swap(__first, __last);
2015 ++__first;
2016 }
2017 }
2018
2019 /**
2020 * @if maint
2021 * This is a helper function for the sort routine.
2022 * @endif
2023 */
2024 template<typename _RandomAccessIterator, typename _Size>
2025 void
2026 __introsort_loop(_RandomAccessIterator __first,
2027 _RandomAccessIterator __last,
2028 _Size __depth_limit)
2029 {
2030 typedef typename iterator_traits<_RandomAccessIterator>::value_type
2031 _ValueType;
2032
2033 while (__last - __first > int(_S_threshold))
2034 {
2035 if (__depth_limit == 0)
2036 {
2037 _GLIBCXX_STD_P:partial_sort(__first, __last, __last);
2038 return;
2039 }
2040 --__depth_limit;
2041 _RandomAccessIterator __cut =
2042 std::__unguarded_partition(__first, __last,
2043 _ValueType(std::__median(*__first,
2044 *(__first
2045 + (__last
2046 - __first)
2047 / 2),
2048 *(__last
2049 - 1))));
2050 std::__introsort_loop(__cut, __last, __depth_limit);
2051 __last = __cut;
2052 }
2053 }
2054
2055 /**
2056 * @if maint
2057 * This is a helper function for the sort routine.
2058 * @endif
2059 */
2060 template<typename _RandomAccessIterator, typename _Size, typename _Compare>
2061 void
2062 __introsort_loop(_RandomAccessIterator __first,
2063 _RandomAccessIterator __last,
2064 _Size __depth_limit, _Compare __comp)
2065 {
2066 typedef typename iterator_traits<_RandomAccessIterator>::value_type
2067 _ValueType;
2068
2069 while (__last - __first > int(_S_threshold))
2070 {
2071 if (__depth_limit == 0)
2072 {
2073 _GLIBCXX_STD_P::partial_sort(__first, __last, __last, __comp);
2074 return;
2075 }
2076 --__depth_limit;
2077 _RandomAccessIterator __cut =
2078 std::__unguarded_partition(__first, __last,
2079 _ValueType(std::__median(*__first,
2080 *(__first
2081 + (__last
2082 - __first)
2083 / 2),
2084 *(__last - 1),
2085 __comp)),
2086 __comp);
2087 std::__introsort_loop(__cut, __last, __depth_limit, __comp);
2088 __last = __cut;
2089 }
2090 }
2091
2092 /**
2093 * @if maint
2094 * This is a helper function for the sort routines.
2095 * @endif
2096 */
2097 template<typename _Size>
2098 inline _Size
2099 __lg(_Size __n)
2100 {
2101 _Size __k;
2102 for (__k = 0; __n != 1; __n >>= 1)
2103 ++__k;
2104 return __k;
2105 }
2106
2107 // sort
2108
2109 template<typename _RandomAccessIterator, typename _Size>
2110 void
2111 __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth,
2112 _RandomAccessIterator __last, _Size __depth_limit)
2113 {
2114 typedef typename iterator_traits<_RandomAccessIterator>::value_type
2115 _ValueType;
2116
2117 while (__last - __first > 3)
2118 {
2119 if (__depth_limit == 0)
2120 {
2121 std::__heap_select(__first, __nth + 1, __last);
2122 // Place the nth largest element in its final position.
2123 std::iter_swap(__first, __nth);
2124 return;
2125 }
2126 --__depth_limit;
2127 _RandomAccessIterator __cut =
2128 std::__unguarded_partition(__first, __last,
2129 _ValueType(std::__median(*__first,
2130 *(__first
2131 + (__last
2132 - __first)
2133 / 2),
2134 *(__last
2135 - 1))));
2136 if (__cut <= __nth)
2137 __first = __cut;
2138 else
2139 __last = __cut;
2140 }
2141 std::__insertion_sort(__first, __last);
2142 }
2143
2144 template<typename _RandomAccessIterator, typename _Size, typename _Compare>
2145 void
2146 __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth,
2147 _RandomAccessIterator __last, _Size __depth_limit,
2148 _Compare __comp)
2149 {
2150 typedef typename iterator_traits<_RandomAccessIterator>::value_type
2151 _ValueType;
2152
2153 while (__last - __first > 3)
2154 {
2155 if (__depth_limit == 0)
2156 {
2157 std::__heap_select(__first, __nth + 1, __last, __comp);
2158 // Place the nth largest element in its final position.
2159 std::iter_swap(__first, __nth);
2160 return;
2161 }
2162 --__depth_limit;
2163 _RandomAccessIterator __cut =
2164 std::__unguarded_partition(__first, __last,
2165 _ValueType(std::__median(*__first,
2166 *(__first
2167 + (__last
2168 - __first)
2169 / 2),
2170 *(__last - 1),
2171 __comp)),
2172 __comp);
2173 if (__cut <= __nth)
2174 __first = __cut;
2175 else
2176 __last = __cut;
2177 }
2178 std::__insertion_sort(__first, __last, __comp);
2179 }
2180
2181 // nth_element
2182
2183 /**
2184 * @brief Finds the first position in which @a val could be inserted
2185 * without changing the ordering.
2186 * @param first An iterator.
2187 * @param last Another iterator.
2188 * @param val The search term.
2189 * @return An iterator pointing to the first element "not less
2190 * than" @a val, or end() if every element is less than
2191 * @a val.
2192 * @ingroup binarysearch
2193 */
2194 template<typename _ForwardIterator, typename _Tp>
2195 _ForwardIterator
2196 lower_bound(_ForwardIterator __first, _ForwardIterator __last,
2197 const _Tp& __val)
2198 {
2199 typedef typename iterator_traits<_ForwardIterator>::value_type
2200 _ValueType;
2201 typedef typename iterator_traits<_ForwardIterator>::difference_type
2202 _DistanceType;
2203
2204 // concept requirements
2205 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2206 __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>)
2207 __glibcxx_requires_partitioned_lower(__first, __last, __val);
2208
2209 _DistanceType __len = std::distance(__first, __last);
2210 _DistanceType __half;
2211 _ForwardIterator __middle;
2212
2213 while (__len > 0)
2214 {
2215 __half = __len >> 1;
2216 __middle = __first;
2217 std::advance(__middle, __half);
2218 if (*__middle < __val)
2219 {
2220 __first = __middle;
2221 ++__first;
2222 __len = __len - __half - 1;
2223 }
2224 else
2225 __len = __half;
2226 }
2227 return __first;
2228 }
2229
2230 /**
2231 * @brief Finds the first position in which @a val could be inserted
2232 * without changing the ordering.
2233 * @param first An iterator.
2234 * @param last Another iterator.
2235 * @param val The search term.
2236 * @param comp A functor to use for comparisons.
2237 * @return An iterator pointing to the first element "not less than" @a val,
2238 * or end() if every element is less than @a val.
2239 * @ingroup binarysearch
2240 *
2241 * The comparison function should have the same effects on ordering as
2242 * the function used for the initial sort.
2243 */
2244 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2245 _ForwardIterator
2246 lower_bound(_ForwardIterator __first, _ForwardIterator __last,
2247 const _Tp& __val, _Compare __comp)
2248 {
2249 typedef typename iterator_traits<_ForwardIterator>::value_type
2250 _ValueType;
2251 typedef typename iterator_traits<_ForwardIterator>::difference_type
2252 _DistanceType;
2253
2254 // concept requirements
2255 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2256 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2257 _ValueType, _Tp>)
2258 __glibcxx_requires_partitioned_lower_pred(__first, __last,
2259 __val, __comp);
2260
2261 _DistanceType __len = std::distance(__first, __last);
2262 _DistanceType __half;
2263 _ForwardIterator __middle;
2264
2265 while (__len > 0)
2266 {
2267 __half = __len >> 1;
2268 __middle = __first;
2269 std::advance(__middle, __half);
2270 if (__comp(*__middle, __val))
2271 {
2272 __first = __middle;
2273 ++__first;
2274 __len = __len - __half - 1;
2275 }
2276 else
2277 __len = __half;
2278 }
2279 return __first;
2280 }
2281
2282 /**
2283 * @brief Finds the last position in which @a val could be inserted
2284 * without changing the ordering.
2285 * @param first An iterator.
2286 * @param last Another iterator.
2287 * @param val The search term.
2288 * @return An iterator pointing to the first element greater than @a val,
2289 * or end() if no elements are greater than @a val.
2290 * @ingroup binarysearch
2291 */
2292 template<typename _ForwardIterator, typename _Tp>
2293 _ForwardIterator
2294 upper_bound(_ForwardIterator __first, _ForwardIterator __last,
2295 const _Tp& __val)
2296 {
2297 typedef typename iterator_traits<_ForwardIterator>::value_type
2298 _ValueType;
2299 typedef typename iterator_traits<_ForwardIterator>::difference_type
2300 _DistanceType;
2301
2302 // concept requirements
2303 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2304 __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>)
2305 __glibcxx_requires_partitioned_upper(__first, __last, __val);
2306
2307 _DistanceType __len = std::distance(__first, __last);
2308 _DistanceType __half;
2309 _ForwardIterator __middle;
2310
2311 while (__len > 0)
2312 {
2313 __half = __len >> 1;
2314 __middle = __first;
2315 std::advance(__middle, __half);
2316 if (__val < *__middle)
2317 __len = __half;
2318 else
2319 {
2320 __first = __middle;
2321 ++__first;
2322 __len = __len - __half - 1;
2323 }
2324 }
2325 return __first;
2326 }
2327
2328 /**
2329 * @brief Finds the last position in which @a val could be inserted
2330 * without changing the ordering.
2331 * @param first An iterator.
2332 * @param last Another iterator.
2333 * @param val The search term.
2334 * @param comp A functor to use for comparisons.
2335 * @return An iterator pointing to the first element greater than @a val,
2336 * or end() if no elements are greater than @a val.
2337 * @ingroup binarysearch
2338 *
2339 * The comparison function should have the same effects on ordering as
2340 * the function used for the initial sort.
2341 */
2342 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2343 _ForwardIterator
2344 upper_bound(_ForwardIterator __first, _ForwardIterator __last,
2345 const _Tp& __val, _Compare __comp)
2346 {
2347 typedef typename iterator_traits<_ForwardIterator>::value_type
2348 _ValueType;
2349 typedef typename iterator_traits<_ForwardIterator>::difference_type
2350 _DistanceType;
2351
2352 // concept requirements
2353 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2354 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2355 _Tp, _ValueType>)
2356 __glibcxx_requires_partitioned_upper_pred(__first, __last,
2357 __val, __comp);
2358
2359 _DistanceType __len = std::distance(__first, __last);
2360 _DistanceType __half;
2361 _ForwardIterator __middle;
2362
2363 while (__len > 0)
2364 {
2365 __half = __len >> 1;
2366 __middle = __first;
2367 std::advance(__middle, __half);
2368 if (__comp(__val, *__middle))
2369 __len = __half;
2370 else
2371 {
2372 __first = __middle;
2373 ++__first;
2374 __len = __len - __half - 1;
2375 }
2376 }
2377 return __first;
2378 }
2379
2380 /**
2381 * @brief Finds the largest subrange in which @a val could be inserted
2382 * at any place in it without changing the ordering.
2383 * @param first An iterator.
2384 * @param last Another iterator.
2385 * @param val The search term.
2386 * @return An pair of iterators defining the subrange.
2387 * @ingroup binarysearch
2388 *
2389 * This is equivalent to
2390 * @code
2391 * std::make_pair(lower_bound(first, last, val),
2392 * upper_bound(first, last, val))
2393 * @endcode
2394 * but does not actually call those functions.
2395 */
2396 template<typename _ForwardIterator, typename _Tp>
2397 pair<_ForwardIterator, _ForwardIterator>
2398 equal_range(_ForwardIterator __first, _ForwardIterator __last,
2399 const _Tp& __val)
2400 {
2401 typedef typename iterator_traits<_ForwardIterator>::value_type
2402 _ValueType;
2403 typedef typename iterator_traits<_ForwardIterator>::difference_type
2404 _DistanceType;
2405
2406 // concept requirements
2407 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2408 __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>)
2409 __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>)
2410 __glibcxx_requires_partitioned_lower(__first, __last, __val);
2411 __glibcxx_requires_partitioned_upper(__first, __last, __val);
2412
2413 _DistanceType __len = std::distance(__first, __last);
2414 _DistanceType __half;
2415 _ForwardIterator __middle, __left, __right;
2416
2417 while (__len > 0)
2418 {
2419 __half = __len >> 1;
2420 __middle = __first;
2421 std::advance(__middle, __half);
2422 if (*__middle < __val)
2423 {
2424 __first = __middle;
2425 ++__first;
2426 __len = __len - __half - 1;
2427 }
2428 else if (__val < *__middle)
2429 __len = __half;
2430 else
2431 {
2432 __left = std::lower_bound(__first, __middle, __val);
2433 std::advance(__first, __len);
2434 __right = std::upper_bound(++__middle, __first, __val);
2435 return pair<_ForwardIterator, _ForwardIterator>(__left, __right);
2436 }
2437 }
2438 return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
2439 }
2440
2441 /**
2442 * @brief Finds the largest subrange in which @a val could be inserted
2443 * at any place in it without changing the ordering.
2444 * @param first An iterator.
2445 * @param last Another iterator.
2446 * @param val The search term.
2447 * @param comp A functor to use for comparisons.
2448 * @return An pair of iterators defining the subrange.
2449 * @ingroup binarysearch
2450 *
2451 * This is equivalent to
2452 * @code
2453 * std::make_pair(lower_bound(first, last, val, comp),
2454 * upper_bound(first, last, val, comp))
2455 * @endcode
2456 * but does not actually call those functions.
2457 */
2458 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2459 pair<_ForwardIterator, _ForwardIterator>
2460 equal_range(_ForwardIterator __first, _ForwardIterator __last,
2461 const _Tp& __val,
2462 _Compare __comp)
2463 {
2464 typedef typename iterator_traits<_ForwardIterator>::value_type
2465 _ValueType;
2466 typedef typename iterator_traits<_ForwardIterator>::difference_type
2467 _DistanceType;
2468
2469 // concept requirements
2470 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2471 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2472 _ValueType, _Tp>)
2473 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2474 _Tp, _ValueType>)
2475 __glibcxx_requires_partitioned_lower_pred(__first, __last,
2476 __val, __comp);
2477 __glibcxx_requires_partitioned_upper_pred(__first, __last,
2478 __val, __comp);
2479
2480 _DistanceType __len = std::distance(__first, __last);
2481 _DistanceType __half;
2482 _ForwardIterator __middle, __left, __right;
2483
2484 while (__len > 0)
2485 {
2486 __half = __len >> 1;
2487 __middle = __first;
2488 std::advance(__middle, __half);
2489 if (__comp(*__middle, __val))
2490 {
2491 __first = __middle;
2492 ++__first;
2493 __len = __len - __half - 1;
2494 }
2495 else if (__comp(__val, *__middle))
2496 __len = __half;
2497 else
2498 {
2499 __left = std::lower_bound(__first, __middle, __val, __comp);
2500 std::advance(__first, __len);
2501 __right = std::upper_bound(++__middle, __first, __val, __comp);
2502 return pair<_ForwardIterator, _ForwardIterator>(__left, __right);
2503 }
2504 }
2505 return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
2506 }
2507
2508 /**
2509 * @brief Determines whether an element exists in a range.
2510 * @param first An iterator.
2511 * @param last Another iterator.
2512 * @param val The search term.
2513 * @return True if @a val (or its equivelent) is in [@a first,@a last ].
2514 * @ingroup binarysearch
2515 *
2516 * Note that this does not actually return an iterator to @a val. For
2517 * that, use std::find or a container's specialized find member functions.
2518 */
2519 template<typename _ForwardIterator, typename _Tp>
2520 bool
2521 binary_search(_ForwardIterator __first, _ForwardIterator __last,
2522 const _Tp& __val)
2523 {
2524 typedef typename iterator_traits<_ForwardIterator>::value_type
2525 _ValueType;
2526
2527 // concept requirements
2528 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2529 __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>)
2530 __glibcxx_requires_partitioned_lower(__first, __last, __val);
2531 __glibcxx_requires_partitioned_upper(__first, __last, __val);
2532
2533 _ForwardIterator __i = std::lower_bound(__first, __last, __val);
2534 return __i != __last && !(__val < *__i);
2535 }
2536
2537 /**
2538 * @brief Determines whether an element exists in a range.
2539 * @param first An iterator.
2540 * @param last Another iterator.
2541 * @param val The search term.
2542 * @param comp A functor to use for comparisons.
2543 * @return True if @a val (or its equivelent) is in [@a first,@a last ].
2544 * @ingroup binarysearch
2545 *
2546 * Note that this does not actually return an iterator to @a val. For
2547 * that, use std::find or a container's specialized find member functions.
2548 *
2549 * The comparison function should have the same effects on ordering as
2550 * the function used for the initial sort.
2551 */
2552 template<typename _ForwardIterator, typename _Tp, typename _Compare>
2553 bool
2554 binary_search(_ForwardIterator __first, _ForwardIterator __last,
2555 const _Tp& __val, _Compare __comp)
2556 {
2557 typedef typename iterator_traits<_ForwardIterator>::value_type
2558 _ValueType;
2559
2560 // concept requirements
2561 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
2562 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2563 _Tp, _ValueType>)
2564 __glibcxx_requires_partitioned_lower_pred(__first, __last,
2565 __val, __comp);
2566 __glibcxx_requires_partitioned_upper_pred(__first, __last,
2567 __val, __comp);
2568
2569 _ForwardIterator __i = std::lower_bound(__first, __last, __val, __comp);
2570 return __i != __last && !bool(__comp(__val, *__i));
2571 }
2572
2573 // merge
2574
2575 /**
2576 * @if maint
2577 * This is a helper function for the merge routines.
2578 * @endif
2579 */
2580 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
2581 typename _BidirectionalIterator3>
2582 _BidirectionalIterator3
2583 __merge_backward(_BidirectionalIterator1 __first1,
2584 _BidirectionalIterator1 __last1,
2585 _BidirectionalIterator2 __first2,
2586 _BidirectionalIterator2 __last2,
2587 _BidirectionalIterator3 __result)
2588 {
2589 if (__first1 == __last1)
2590 return std::copy_backward(__first2, __last2, __result);
2591 if (__first2 == __last2)
2592 return std::copy_backward(__first1, __last1, __result);
2593 --__last1;
2594 --__last2;
2595 while (true)
2596 {
2597 if (*__last2 < *__last1)
2598 {
2599 *--__result = *__last1;
2600 if (__first1 == __last1)
2601 return std::copy_backward(__first2, ++__last2, __result);
2602 --__last1;
2603 }
2604 else
2605 {
2606 *--__result = *__last2;
2607 if (__first2 == __last2)
2608 return std::copy_backward(__first1, ++__last1, __result);
2609 --__last2;
2610 }
2611 }
2612 }
2613
2614 /**
2615 * @if maint
2616 * This is a helper function for the merge routines.
2617 * @endif
2618 */
2619 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
2620 typename _BidirectionalIterator3, typename _Compare>
2621 _BidirectionalIterator3
2622 __merge_backward(_BidirectionalIterator1 __first1,
2623 _BidirectionalIterator1 __last1,
2624 _BidirectionalIterator2 __first2,
2625 _BidirectionalIterator2 __last2,
2626 _BidirectionalIterator3 __result,
2627 _Compare __comp)
2628 {
2629 if (__first1 == __last1)
2630 return std::copy_backward(__first2, __last2, __result);
2631 if (__first2 == __last2)
2632 return std::copy_backward(__first1, __last1, __result);
2633 --__last1;
2634 --__last2;
2635 while (true)
2636 {
2637 if (__comp(*__last2, *__last1))
2638 {
2639 *--__result = *__last1;
2640 if (__first1 == __last1)
2641 return std::copy_backward(__first2, ++__last2, __result);
2642 --__last1;
2643 }
2644 else
2645 {
2646 *--__result = *__last2;
2647 if (__first2 == __last2)
2648 return std::copy_backward(__first1, ++__last1, __result);
2649 --__last2;
2650 }
2651 }
2652 }
2653
2654 /**
2655 * @if maint
2656 * This is a helper function for the merge routines.
2657 * @endif
2658 */
2659 template<typename _BidirectionalIterator1, typename _BidirectionalIterator2,
2660 typename _Distance>
2661 _BidirectionalIterator1
2662 __rotate_adaptive(_BidirectionalIterator1 __first,
2663 _BidirectionalIterator1 __middle,
2664 _BidirectionalIterator1 __last,
2665 _Distance __len1, _Distance __len2,
2666 _BidirectionalIterator2 __buffer,
2667 _Distance __buffer_size)
2668 {
2669 _BidirectionalIterator2 __buffer_end;
2670 if (__len1 > __len2 && __len2 <= __buffer_size)
2671 {
2672 __buffer_end = std::copy(__middle, __last, __buffer);
2673 std::copy_backward(__first, __middle, __last);
2674 return std::copy(__buffer, __buffer_end, __first);
2675 }
2676 else if (__len1 <= __buffer_size)
2677 {
2678 __buffer_end = std::copy(__first, __middle, __buffer);
2679 std::copy(__middle, __last, __first);
2680 return std::copy_backward(__buffer, __buffer_end, __last);
2681 }
2682 else
2683 {
2684 std::rotate(__first, __middle, __last);
2685 std::advance(__first, std::distance(__middle, __last));
2686 return __first;
2687 }
2688 }
2689
2690 /**
2691 * @if maint
2692 * This is a helper function for the merge routines.
2693 * @endif
2694 */
2695 template<typename _BidirectionalIterator, typename _Distance,
2696 typename _Pointer>
2697 void
2698 __merge_adaptive(_BidirectionalIterator __first,
2699 _BidirectionalIterator __middle,
2700 _BidirectionalIterator __last,
2701 _Distance __len1, _Distance __len2,
2702 _Pointer __buffer, _Distance __buffer_size)
2703 {
2704 if (__len1 <= __len2 && __len1 <= __buffer_size)
2705 {
2706 _Pointer __buffer_end = std::copy(__first, __middle, __buffer);
2707 _GLIBCXX_STD_P::merge(__buffer, __buffer_end, __middle, __last,
2708 __first);
2709 }
2710 else if (__len2 <= __buffer_size)
2711 {
2712 _Pointer __buffer_end = std::copy(__middle, __last, __buffer);
2713 std::__merge_backward(__first, __middle, __buffer,
2714 __buffer_end, __last);
2715 }
2716 else
2717 {
2718 _BidirectionalIterator __first_cut = __first;
2719 _BidirectionalIterator __second_cut = __middle;
2720 _Distance __len11 = 0;
2721 _Distance __len22 = 0;
2722 if (__len1 > __len2)
2723 {
2724 __len11 = __len1 / 2;
2725 std::advance(__first_cut, __len11);
2726 __second_cut = std::lower_bound(__middle, __last,
2727 *__first_cut);
2728 __len22 = std::distance(__middle, __second_cut);
2729 }
2730 else
2731 {
2732 __len22 = __len2 / 2;
2733 std::advance(__second_cut, __len22);
2734 __first_cut = std::upper_bound(__first, __middle,
2735 *__second_cut);
2736 __len11 = std::distance(__first, __first_cut);
2737 }
2738 _BidirectionalIterator __new_middle =
2739 std::__rotate_adaptive(__first_cut, __middle, __second_cut,
2740 __len1 - __len11, __len22, __buffer,
2741 __buffer_size);
2742 std::__merge_adaptive(__first, __first_cut, __new_middle, __len11,
2743 __len22, __buffer, __buffer_size);
2744 std::__merge_adaptive(__new_middle, __second_cut, __last,
2745 __len1 - __len11,
2746 __len2 - __len22, __buffer, __buffer_size);
2747 }
2748 }
2749
2750 /**
2751 * @if maint
2752 * This is a helper function for the merge routines.
2753 * @endif
2754 */
2755 template<typename _BidirectionalIterator, typename _Distance,
2756 typename _Pointer, typename _Compare>
2757 void
2758 __merge_adaptive(_BidirectionalIterator __first,
2759 _BidirectionalIterator __middle,
2760 _BidirectionalIterator __last,
2761 _Distance __len1, _Distance __len2,
2762 _Pointer __buffer, _Distance __buffer_size,
2763 _Compare __comp)
2764 {
2765 if (__len1 <= __len2 && __len1 <= __buffer_size)
2766 {
2767 _Pointer __buffer_end = std::copy(__first, __middle, __buffer);
2768 _GLIBCXX_STD_P::merge(__buffer, __buffer_end, __middle, __last,
2769 __first, __comp);
2770 }
2771 else if (__len2 <= __buffer_size)
2772 {
2773 _Pointer __buffer_end = std::copy(__middle, __last, __buffer);
2774 std::__merge_backward(__first, __middle, __buffer, __buffer_end,
2775 __last, __comp);
2776 }
2777 else
2778 {
2779 _BidirectionalIterator __first_cut = __first;
2780 _BidirectionalIterator __second_cut = __middle;
2781 _Distance __len11 = 0;
2782 _Distance __len22 = 0;
2783 if (__len1 > __len2)
2784 {
2785 __len11 = __len1 / 2;
2786 std::advance(__first_cut, __len11);
2787 __second_cut = std::lower_bound(__middle, __last, *__first_cut,
2788 __comp);
2789 __len22 = std::distance(__middle, __second_cut);
2790 }
2791 else
2792 {
2793 __len22 = __len2 / 2;
2794 std::advance(__second_cut, __len22);
2795 __first_cut = std::upper_bound(__first, __middle, *__second_cut,
2796 __comp);
2797 __len11 = std::distance(__first, __first_cut);
2798 }
2799 _BidirectionalIterator __new_middle =
2800 std::__rotate_adaptive(__first_cut, __middle, __second_cut,
2801 __len1 - __len11, __len22, __buffer,
2802 __buffer_size);
2803 std::__merge_adaptive(__first, __first_cut, __new_middle, __len11,
2804 __len22, __buffer, __buffer_size, __comp);
2805 std::__merge_adaptive(__new_middle, __second_cut, __last,
2806 __len1 - __len11,
2807 __len2 - __len22, __buffer,
2808 __buffer_size, __comp);
2809 }
2810 }
2811
2812 /**
2813 * @if maint
2814 * This is a helper function for the merge routines.
2815 * @endif
2816 */
2817 template<typename _BidirectionalIterator, typename _Distance>
2818 void
2819 __merge_without_buffer(_BidirectionalIterator __first,
2820 _BidirectionalIterator __middle,
2821 _BidirectionalIterator __last,
2822 _Distance __len1, _Distance __len2)
2823 {
2824 if (__len1 == 0 || __len2 == 0)
2825 return;
2826 if (__len1 + __len2 == 2)
2827 {
2828 if (*__middle < *__first)
2829 std::iter_swap(__first, __middle);
2830 return;
2831 }
2832 _BidirectionalIterator __first_cut = __first;
2833 _BidirectionalIterator __second_cut = __middle;
2834 _Distance __len11 = 0;
2835 _Distance __len22 = 0;
2836 if (__len1 > __len2)
2837 {
2838 __len11 = __len1 / 2;
2839 std::advance(__first_cut, __len11);
2840 __second_cut = std::lower_bound(__middle, __last, *__first_cut);
2841 __len22 = std::distance(__middle, __second_cut);
2842 }
2843 else
2844 {
2845 __len22 = __len2 / 2;
2846 std::advance(__second_cut, __len22);
2847 __first_cut = std::upper_bound(__first, __middle, *__second_cut);
2848 __len11 = std::distance(__first, __first_cut);
2849 }
2850 std::rotate(__first_cut, __middle, __second_cut);
2851 _BidirectionalIterator __new_middle = __first_cut;
2852 std::advance(__new_middle, std::distance(__middle, __second_cut));
2853 std::__merge_without_buffer(__first, __first_cut, __new_middle,
2854 __len11, __len22);
2855 std::__merge_without_buffer(__new_middle, __second_cut, __last,
2856 __len1 - __len11, __len2 - __len22);
2857 }
2858
2859 /**
2860 * @if maint
2861 * This is a helper function for the merge routines.
2862 * @endif
2863 */
2864 template<typename _BidirectionalIterator, typename _Distance,
2865 typename _Compare>
2866 void
2867 __merge_without_buffer(_BidirectionalIterator __first,
2868 _BidirectionalIterator __middle,
2869 _BidirectionalIterator __last,
2870 _Distance __len1, _Distance __len2,
2871 _Compare __comp)
2872 {
2873 if (__len1 == 0 || __len2 == 0)
2874 return;
2875 if (__len1 + __len2 == 2)
2876 {
2877 if (__comp(*__middle, *__first))
2878 std::iter_swap(__first, __middle);
2879 return;
2880 }
2881 _BidirectionalIterator __first_cut = __first;
2882 _BidirectionalIterator __second_cut = __middle;
2883 _Distance __len11 = 0;
2884 _Distance __len22 = 0;
2885 if (__len1 > __len2)
2886 {
2887 __len11 = __len1 / 2;
2888 std::advance(__first_cut, __len11);
2889 __second_cut = std::lower_bound(__middle, __last, *__first_cut,
2890 __comp);
2891 __len22 = std::distance(__middle, __second_cut);
2892 }
2893 else
2894 {
2895 __len22 = __len2 / 2;
2896 std::advance(__second_cut, __len22);
2897 __first_cut = std::upper_bound(__first, __middle, *__second_cut,
2898 __comp);
2899 __len11 = std::distance(__first, __first_cut);
2900 }
2901 std::rotate(__first_cut, __middle, __second_cut);
2902 _BidirectionalIterator __new_middle = __first_cut;
2903 std::advance(__new_middle, std::distance(__middle, __second_cut));
2904 std::__merge_without_buffer(__first, __first_cut, __new_middle,
2905 __len11, __len22, __comp);
2906 std::__merge_without_buffer(__new_middle, __second_cut, __last,
2907 __len1 - __len11, __len2 - __len22, __comp);
2908 }
2909
2910 /**
2911 * @brief Merges two sorted ranges in place.
2912 * @param first An iterator.
2913 * @param middle Another iterator.
2914 * @param last Another iterator.
2915 * @return Nothing.
2916 *
2917 * Merges two sorted and consecutive ranges, [first,middle) and
2918 * [middle,last), and puts the result in [first,last). The output will
2919 * be sorted. The sort is @e stable, that is, for equivalent
2920 * elements in the two ranges, elements from the first range will always
2921 * come before elements from the second.
2922 *
2923 * If enough additional memory is available, this takes (last-first)-1
2924 * comparisons. Otherwise an NlogN algorithm is used, where N is
2925 * distance(first,last).
2926 */
2927 template<typename _BidirectionalIterator>
2928 void
2929 inplace_merge(_BidirectionalIterator __first,
2930 _BidirectionalIterator __middle,
2931 _BidirectionalIterator __last)
2932 {
2933 typedef typename iterator_traits<_BidirectionalIterator>::value_type
2934 _ValueType;
2935 typedef typename iterator_traits<_BidirectionalIterator>::difference_type
2936 _DistanceType;
2937
2938 // concept requirements
2939 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
2940 _BidirectionalIterator>)
2941 __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
2942 __glibcxx_requires_sorted(__first, __middle);
2943 __glibcxx_requires_sorted(__middle, __last);
2944
2945 if (__first == __middle || __middle == __last)
2946 return;
2947
2948 _DistanceType __len1 = std::distance(__first, __middle);
2949 _DistanceType __len2 = std::distance(__middle, __last);
2950
2951 _Temporary_buffer<_BidirectionalIterator, _ValueType> __buf(__first,
2952 __last);
2953 if (__buf.begin() == 0)
2954 std::__merge_without_buffer(__first, __middle, __last, __len1, __len2);
2955 else
2956 std::__merge_adaptive(__first, __middle, __last, __len1, __len2,
2957 __buf.begin(), _DistanceType(__buf.size()));
2958 }
2959
2960 /**
2961 * @brief Merges two sorted ranges in place.
2962 * @param first An iterator.
2963 * @param middle Another iterator.
2964 * @param last Another iterator.
2965 * @param comp A functor to use for comparisons.
2966 * @return Nothing.
2967 *
2968 * Merges two sorted and consecutive ranges, [first,middle) and
2969 * [middle,last), and puts the result in [first,last). The output will
2970 * be sorted. The sort is @e stable, that is, for equivalent
2971 * elements in the two ranges, elements from the first range will always
2972 * come before elements from the second.
2973 *
2974 * If enough additional memory is available, this takes (last-first)-1
2975 * comparisons. Otherwise an NlogN algorithm is used, where N is
2976 * distance(first,last).
2977 *
2978 * The comparison function should have the same effects on ordering as
2979 * the function used for the initial sort.
2980 */
2981 template<typename _BidirectionalIterator, typename _Compare>
2982 void
2983 inplace_merge(_BidirectionalIterator __first,
2984 _BidirectionalIterator __middle,
2985 _BidirectionalIterator __last,
2986 _Compare __comp)
2987 {
2988 typedef typename iterator_traits<_BidirectionalIterator>::value_type
2989 _ValueType;
2990 typedef typename iterator_traits<_BidirectionalIterator>::difference_type
2991 _DistanceType;
2992
2993 // concept requirements
2994 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<
2995 _BidirectionalIterator>)
2996 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
2997 _ValueType, _ValueType>)
2998 __glibcxx_requires_sorted_pred(__first, __middle, __comp);
2999 __glibcxx_requires_sorted_pred(__middle, __last, __comp);
3000
3001 if (__first == __middle || __middle == __last)
3002 return;
3003
3004 const _DistanceType __len1 = std::distance(__first, __middle);
3005 const _DistanceType __len2 = std::distance(__middle, __last);
3006
3007 _Temporary_buffer<_BidirectionalIterator, _ValueType> __buf(__first,
3008 __last);
3009 if (__buf.begin() == 0)
3010 std::__merge_without_buffer(__first, __middle, __last, __len1,
3011 __len2, __comp);
3012 else
3013 std::__merge_adaptive(__first, __middle, __last, __len1, __len2,
3014 __buf.begin(), _DistanceType(__buf.size()),
3015 __comp);
3016 }
3017
3018 template<typename _RandomAccessIterator1, typename _RandomAccessIterator2,
3019 typename _Distance>
3020 void
3021 __merge_sort_loop(_RandomAccessIterator1 __first,
3022 _RandomAccessIterator1 __last,
3023 _RandomAccessIterator2 __result,
3024 _Distance __step_size)
3025 {
3026 const _Distance __two_step = 2 * __step_size;
3027
3028 while (__last - __first >= __two_step)
3029 {
3030 __result = _GLIBCXX_STD_P::merge(__first, __first + __step_size,
3031 __first + __step_size, __first + __two_step,
3032 __result);
3033 __first += __two_step;
3034 }
3035
3036 __step_size = std::min(_Distance(__last - __first), __step_size);
3037 _GLIBCXX_STD_P::merge(__first, __first + __step_size,
3038 __first + __step_size, __last,
3039 __result);
3040 }
3041
3042 template<typename _RandomAccessIterator1, typename _RandomAccessIterator2,
3043 typename _Distance, typename _Compare>
3044 void
3045 __merge_sort_loop(_RandomAccessIterator1 __first,
3046 _RandomAccessIterator1 __last,
3047 _RandomAccessIterator2 __result, _Distance __step_size,
3048 _Compare __comp)
3049 {
3050 const _Distance __two_step = 2 * __step_size;
3051
3052 while (__last - __first >= __two_step)
3053 {
3054 __result = _GLIBCXX_STD_P::merge(__first, __first + __step_size,
3055 __first + __step_size, __first + __two_step,
3056 __result,
3057 __comp);
3058 __first += __two_step;
3059 }
3060 __step_size = std::min(_Distance(__last - __first), __step_size);
3061
3062 _GLIBCXX_STD_P::merge(__first, __first + __step_size,
3063 __first + __step_size, __last, __result, __comp);
3064 }
3065
3066 template<typename _RandomAccessIterator, typename _Distance>
3067 void
3068 __chunk_insertion_sort(_RandomAccessIterator __first,
3069 _RandomAccessIterator __last,
3070 _Distance __chunk_size)
3071 {
3072 while (__last - __first >= __chunk_size)
3073 {
3074 std::__insertion_sort(__first, __first + __chunk_size);
3075 __first += __chunk_size;
3076 }
3077 std::__insertion_sort(__first, __last);
3078 }
3079
3080 template<typename _RandomAccessIterator, typename _Distance,
3081 typename _Compare>
3082 void
3083 __chunk_insertion_sort(_RandomAccessIterator __first,
3084 _RandomAccessIterator __last,
3085 _Distance __chunk_size, _Compare __comp)
3086 {
3087 while (__last - __first >= __chunk_size)
3088 {
3089 std::__insertion_sort(__first, __first + __chunk_size, __comp);
3090 __first += __chunk_size;
3091 }
3092 std::__insertion_sort(__first, __last, __comp);
3093 }
3094
3095 enum { _S_chunk_size = 7 };
3096
3097 template<typename _RandomAccessIterator, typename _Pointer>
3098 void
3099 __merge_sort_with_buffer(_RandomAccessIterator __first,
3100 _RandomAccessIterator __last,
3101 _Pointer __buffer)
3102 {
3103 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
3104 _Distance;
3105
3106 const _Distance __len = __last - __first;
3107 const _Pointer __buffer_last = __buffer + __len;
3108
3109 _Distance __step_size = _S_chunk_size;
3110 std::__chunk_insertion_sort(__first, __last, __step_size);
3111
3112 while (__step_size < __len)
3113 {
3114 std::__merge_sort_loop(__first, __last, __buffer, __step_size);
3115 __step_size *= 2;
3116 std::__merge_sort_loop(__buffer, __buffer_last, __first, __step_size);
3117 __step_size *= 2;
3118 }
3119 }
3120
3121 template<typename _RandomAccessIterator, typename _Pointer, typename _Compare>
3122 void
3123 __merge_sort_with_buffer(_RandomAccessIterator __first,
3124 _RandomAccessIterator __last,
3125 _Pointer __buffer, _Compare __comp)
3126 {
3127 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
3128 _Distance;
3129
3130 const _Distance __len = __last - __first;
3131 const _Pointer __buffer_last = __buffer + __len;
3132
3133 _Distance __step_size = _S_chunk_size;
3134 std::__chunk_insertion_sort(__first, __last, __step_size, __comp);
3135
3136 while (__step_size < __len)
3137 {
3138 std::__merge_sort_loop(__first, __last, __buffer,
3139 __step_size, __comp);
3140 __step_size *= 2;
3141 std::__merge_sort_loop(__buffer, __buffer_last, __first,
3142 __step_size, __comp);
3143 __step_size *= 2;
3144 }
3145 }
3146
3147 template<typename _RandomAccessIterator, typename _Pointer,
3148 typename _Distance>
3149 void
3150 __stable_sort_adaptive(_RandomAccessIterator __first,
3151 _RandomAccessIterator __last,
3152 _Pointer __buffer, _Distance __buffer_size)
3153 {
3154 const _Distance __len = (__last - __first + 1) / 2;
3155 const _RandomAccessIterator __middle = __first + __len;
3156 if (__len > __buffer_size)
3157 {
3158 std::__stable_sort_adaptive(__first, __middle,
3159 __buffer, __buffer_size);
3160 std::__stable_sort_adaptive(__middle, __last,
3161 __buffer, __buffer_size);
3162 }
3163 else
3164 {
3165 std::__merge_sort_with_buffer(__first, __middle, __buffer);
3166 std::__merge_sort_with_buffer(__middle, __last, __buffer);
3167 }
3168 std::__merge_adaptive(__first, __middle, __last,
3169 _Distance(__middle - __first),
3170 _Distance(__last - __middle),
3171 __buffer, __buffer_size);
3172 }
3173
3174 template<typename _RandomAccessIterator, typename _Pointer,
3175 typename _Distance, typename _Compare>
3176 void
3177 __stable_sort_adaptive(_RandomAccessIterator __first,
3178 _RandomAccessIterator __last,
3179 _Pointer __buffer, _Distance __buffer_size,
3180 _Compare __comp)
3181 {
3182 const _Distance __len = (__last - __first + 1) / 2;
3183 const _RandomAccessIterator __middle = __first + __len;
3184 if (__len > __buffer_size)
3185 {
3186 std::__stable_sort_adaptive(__first, __middle, __buffer,
3187 __buffer_size, __comp);
3188 std::__stable_sort_adaptive(__middle, __last, __buffer,
3189 __buffer_size, __comp);
3190 }
3191 else
3192 {
3193 std::__merge_sort_with_buffer(__first, __middle, __buffer, __comp);
3194 std::__merge_sort_with_buffer(__middle, __last, __buffer, __comp);
3195 }
3196 std::__merge_adaptive(__first, __middle, __last,
3197 _Distance(__middle - __first),
3198 _Distance(__last - __middle),
3199 __buffer, __buffer_size,
3200 __comp);
3201 }
3202
3203 /**
3204 * @if maint
3205 * This is a helper function for the stable sorting routines.
3206 * @endif
3207 */
3208 template<typename _RandomAccessIterator>
3209 void
3210 __inplace_stable_sort(_RandomAccessIterator __first,
3211 _RandomAccessIterator __last)
3212 {
3213 if (__last - __first < 15)
3214 {
3215 std::__insertion_sort(__first, __last);
3216 return;
3217 }
3218 _RandomAccessIterator __middle = __first + (__last - __first) / 2;
3219 std::__inplace_stable_sort(__first, __middle);
3220 std::__inplace_stable_sort(__middle, __last);
3221 std::__merge_without_buffer(__first, __middle, __last,
3222 __middle - __first,
3223 __last - __middle);
3224 }
3225
3226 /**
3227 * @if maint
3228 * This is a helper function for the stable sorting routines.
3229 * @endif
3230 */
3231 template<typename _RandomAccessIterator, typename _Compare>
3232 void
3233 __inplace_stable_sort(_RandomAccessIterator __first,
3234 _RandomAccessIterator __last, _Compare __comp)
3235 {
3236 if (__last - __first < 15)
3237 {
3238 std::__insertion_sort(__first, __last, __comp);
3239 return;
3240 }
3241 _RandomAccessIterator __middle = __first + (__last - __first) / 2;
3242 std::__inplace_stable_sort(__first, __middle, __comp);
3243 std::__inplace_stable_sort(__middle, __last, __comp);
3244 std::__merge_without_buffer(__first, __middle, __last,
3245 __middle - __first,
3246 __last - __middle,
3247 __comp);
3248 }
3249
3250 // stable_sort
3251
3252 // Set algorithms: includes, set_union, set_intersection, set_difference,
3253 // set_symmetric_difference. All of these algorithms have the precondition
3254 // that their input ranges are sorted and the postcondition that their output
3255 // ranges are sorted.
3256
3257 /**
3258 * @brief Determines whether all elements of a sequence exists in a range.
3259 * @param first1 Start of search range.
3260 * @param last1 End of search range.
3261 * @param first2 Start of sequence
3262 * @param last2 End of sequence.
3263 * @return True if each element in [first2,last2) is contained in order
3264 * within [first1,last1). False otherwise.
3265 * @ingroup setoperations
3266 *
3267 * This operation expects both [first1,last1) and [first2,last2) to be
3268 * sorted. Searches for the presence of each element in [first2,last2)
3269 * within [first1,last1). The iterators over each range only move forward,
3270 * so this is a linear algorithm. If an element in [first2,last2) is not
3271 * found before the search iterator reaches @a last2, false is returned.
3272 */
3273 template<typename _InputIterator1, typename _InputIterator2>
3274 bool
3275 includes(_InputIterator1 __first1, _InputIterator1 __last1,
3276 _InputIterator2 __first2, _InputIterator2 __last2)
3277 {
3278 typedef typename iterator_traits<_InputIterator1>::value_type
3279 _ValueType1;
3280 typedef typename iterator_traits<_InputIterator2>::value_type
3281 _ValueType2;
3282
3283 // concept requirements
3284 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
3285 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
3286 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
3287 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
3288 __glibcxx_requires_sorted(__first1, __last1);
3289 __glibcxx_requires_sorted(__first2, __last2);
3290
3291 while (__first1 != __last1 && __first2 != __last2)
3292 if (*__first2 < *__first1)
3293 return false;
3294 else if(*__first1 < *__first2)
3295 ++__first1;
3296 else
3297 ++__first1, ++__first2;
3298
3299 return __first2 == __last2;
3300 }
3301
3302 /**
3303 * @brief Determines whether all elements of a sequence exists in a range
3304 * using comparison.
3305 * @param first1 Start of search range.
3306 * @param last1 End of search range.
3307 * @param first2 Start of sequence
3308 * @param last2 End of sequence.
3309 * @param comp Comparison function to use.
3310 * @return True if each element in [first2,last2) is contained in order
3311 * within [first1,last1) according to comp. False otherwise.
3312 * @ingroup setoperations
3313 *
3314 * This operation expects both [first1,last1) and [first2,last2) to be
3315 * sorted. Searches for the presence of each element in [first2,last2)
3316 * within [first1,last1), using comp to decide. The iterators over each
3317 * range only move forward, so this is a linear algorithm. If an element
3318 * in [first2,last2) is not found before the search iterator reaches @a
3319 * last2, false is returned.
3320 */
3321 template<typename _InputIterator1, typename _InputIterator2,
3322 typename _Compare>
3323 bool
3324 includes(_InputIterator1 __first1, _InputIterator1 __last1,
3325 _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
3326 {
3327 typedef typename iterator_traits<_InputIterator1>::value_type
3328 _ValueType1;
3329 typedef typename iterator_traits<_InputIterator2>::value_type
3330 _ValueType2;
3331
3332 // concept requirements
3333 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
3334 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
3335 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3336 _ValueType1, _ValueType2>)
3337 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3338 _ValueType2, _ValueType1>)
3339 __glibcxx_requires_sorted_pred(__first1, __last1, __comp);
3340 __glibcxx_requires_sorted_pred(__first2, __last2, __comp);
3341
3342 while (__first1 != __last1 && __first2 != __last2)
3343 if (__comp(*__first2, *__first1))
3344 return false;
3345 else if(__comp(*__first1, *__first2))
3346 ++__first1;
3347 else
3348 ++__first1, ++__first2;
3349
3350 return __first2 == __last2;
3351 }
3352
3353 // nth_element
3354 // merge
3355 // set_difference
3356 // set_intersection
3357 // set_union
3358 // stable_sort
3359 // set_symmetric_difference
3360 // min_element
3361 // max_element
3362
3363 /**
3364 * @brief Permute range into the next "dictionary" ordering.
3365 * @param first Start of range.
3366 * @param last End of range.
3367 * @return False if wrapped to first permutation, true otherwise.
3368 *
3369 * Treats all permutations of the range as a set of "dictionary" sorted
3370 * sequences. Permutes the current sequence into the next one of this set.
3371 * Returns true if there are more sequences to generate. If the sequence
3372 * is the largest of the set, the smallest is generated and false returned.
3373 */
3374 template<typename _BidirectionalIterator>
3375 bool
3376 next_permutation(_BidirectionalIterator __first,
3377 _BidirectionalIterator __last)
3378 {
3379 // concept requirements
3380 __glibcxx_function_requires(_BidirectionalIteratorConcept<
3381 _BidirectionalIterator>)
3382 __glibcxx_function_requires(_LessThanComparableConcept<
3383 typename iterator_traits<_BidirectionalIterator>::value_type>)
3384 __glibcxx_requires_valid_range(__first, __last);
3385
3386 if (__first == __last)
3387 return false;
3388 _BidirectionalIterator __i = __first;
3389 ++__i;
3390 if (__i == __last)
3391 return false;
3392 __i = __last;
3393 --__i;
3394
3395 for(;;)
3396 {
3397 _BidirectionalIterator __ii = __i;
3398 --__i;
3399 if (*__i < *__ii)
3400 {
3401 _BidirectionalIterator __j = __last;
3402 while (!(*__i < *--__j))
3403 {}
3404 std::iter_swap(__i, __j);
3405 std::reverse(__ii, __last);
3406 return true;
3407 }
3408 if (__i == __first)
3409 {
3410 std::reverse(__first, __last);
3411 return false;
3412 }
3413 }
3414 }
3415
3416 /**
3417 * @brief Permute range into the next "dictionary" ordering using
3418 * comparison functor.
3419 * @param first Start of range.
3420 * @param last End of range.
3421 * @param comp
3422 * @return False if wrapped to first permutation, true otherwise.
3423 *
3424 * Treats all permutations of the range [first,last) as a set of
3425 * "dictionary" sorted sequences ordered by @a comp. Permutes the current
3426 * sequence into the next one of this set. Returns true if there are more
3427 * sequences to generate. If the sequence is the largest of the set, the
3428 * smallest is generated and false returned.
3429 */
3430 template<typename _BidirectionalIterator, typename _Compare>
3431 bool
3432 next_permutation(_BidirectionalIterator __first,
3433 _BidirectionalIterator __last, _Compare __comp)
3434 {
3435 // concept requirements
3436 __glibcxx_function_requires(_BidirectionalIteratorConcept<
3437 _BidirectionalIterator>)
3438 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3439 typename iterator_traits<_BidirectionalIterator>::value_type,
3440 typename iterator_traits<_BidirectionalIterator>::value_type>)
3441 __glibcxx_requires_valid_range(__first, __last);
3442
3443 if (__first == __last)
3444 return false;
3445 _BidirectionalIterator __i = __first;
3446 ++__i;
3447 if (__i == __last)
3448 return false;
3449 __i = __last;
3450 --__i;
3451
3452 for(;;)
3453 {
3454 _BidirectionalIterator __ii = __i;
3455 --__i;
3456 if (__comp(*__i, *__ii))
3457 {
3458 _BidirectionalIterator __j = __last;
3459 while (!bool(__comp(*__i, *--__j)))
3460 {}
3461 std::iter_swap(__i, __j);
3462 std::reverse(__ii, __last);
3463 return true;
3464 }
3465 if (__i == __first)
3466 {
3467 std::reverse(__first, __last);
3468 return false;
3469 }
3470 }
3471 }
3472
3473 /**
3474 * @brief Permute range into the previous "dictionary" ordering.
3475 * @param first Start of range.
3476 * @param last End of range.
3477 * @return False if wrapped to last permutation, true otherwise.
3478 *
3479 * Treats all permutations of the range as a set of "dictionary" sorted
3480 * sequences. Permutes the current sequence into the previous one of this
3481 * set. Returns true if there are more sequences to generate. If the
3482 * sequence is the smallest of the set, the largest is generated and false
3483 * returned.
3484 */
3485 template<typename _BidirectionalIterator>
3486 bool
3487 prev_permutation(_BidirectionalIterator __first,
3488 _BidirectionalIterator __last)
3489 {
3490 // concept requirements
3491 __glibcxx_function_requires(_BidirectionalIteratorConcept<
3492 _BidirectionalIterator>)
3493 __glibcxx_function_requires(_LessThanComparableConcept<
3494 typename iterator_traits<_BidirectionalIterator>::value_type>)
3495 __glibcxx_requires_valid_range(__first, __last);
3496
3497 if (__first == __last)
3498 return false;
3499 _BidirectionalIterator __i = __first;
3500 ++__i;
3501 if (__i == __last)
3502 return false;
3503 __i = __last;
3504 --__i;
3505
3506 for(;;)
3507 {
3508 _BidirectionalIterator __ii = __i;
3509 --__i;
3510 if (*__ii < *__i)
3511 {
3512 _BidirectionalIterator __j = __last;
3513 while (!(*--__j < *__i))
3514 {}
3515 std::iter_swap(__i, __j);
3516 std::reverse(__ii, __last);
3517 return true;
3518 }
3519 if (__i == __first)
3520 {
3521 std::reverse(__first, __last);
3522 return false;
3523 }
3524 }
3525 }
3526
3527 /**
3528 * @brief Permute range into the previous "dictionary" ordering using
3529 * comparison functor.
3530 * @param first Start of range.
3531 * @param last End of range.
3532 * @param comp
3533 * @return False if wrapped to last permutation, true otherwise.
3534 *
3535 * Treats all permutations of the range [first,last) as a set of
3536 * "dictionary" sorted sequences ordered by @a comp. Permutes the current
3537 * sequence into the previous one of this set. Returns true if there are
3538 * more sequences to generate. If the sequence is the smallest of the set,
3539 * the largest is generated and false returned.
3540 */
3541 template<typename _BidirectionalIterator, typename _Compare>
3542 bool
3543 prev_permutation(_BidirectionalIterator __first,
3544 _BidirectionalIterator __last, _Compare __comp)
3545 {
3546 // concept requirements
3547 __glibcxx_function_requires(_BidirectionalIteratorConcept<
3548 _BidirectionalIterator>)
3549 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
3550 typename iterator_traits<_BidirectionalIterator>::value_type,
3551 typename iterator_traits<_BidirectionalIterator>::value_type>)
3552 __glibcxx_requires_valid_range(__first, __last);
3553
3554 if (__first == __last)
3555 return false;
3556 _BidirectionalIterator __i = __first;
3557 ++__i;
3558 if (__i == __last)
3559 return false;
3560 __i = __last;
3561 --__i;
3562
3563 for(;;)
3564 {
3565 _BidirectionalIterator __ii = __i;
3566 --__i;
3567 if (__comp(*__ii, *__i))
3568 {
3569 _BidirectionalIterator __j = __last;
3570 while (!bool(__comp(*--__j, *__i)))
3571 {}
3572 std::iter_swap(__i, __j);
3573 std::reverse(__ii, __last);
3574 return true;
3575 }
3576 if (__i == __first)
3577 {
3578 std::reverse(__first, __last);
3579 return false;
3580 }
3581 }
3582 }
3583
3584 // replace
3585 // replace_if
3586
3587 /**
3588 * @brief Copy a sequence, replacing each element of one value with another
3589 * value.
3590 * @param first An input iterator.
3591 * @param last An input iterator.
3592 * @param result An output iterator.
3593 * @param old_value The value to be replaced.
3594 * @param new_value The replacement value.
3595 * @return The end of the output sequence, @p result+(last-first).
3596 *
3597 * Copies each element in the input range @p [first,last) to the
3598 * output range @p [result,result+(last-first)) replacing elements
3599 * equal to @p old_value with @p new_value.
3600 */
3601 template<typename _InputIterator, typename _OutputIterator, typename _Tp>
3602 _OutputIterator
3603 replace_copy(_InputIterator __first, _InputIterator __last,
3604 _OutputIterator __result,
3605 const _Tp& __old_value, const _Tp& __new_value)
3606 {
3607 // concept requirements
3608 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3609 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
3610 typename iterator_traits<_InputIterator>::value_type>)
3611 __glibcxx_function_requires(_EqualOpConcept<
3612 typename iterator_traits<_InputIterator>::value_type, _Tp>)
3613 __glibcxx_requires_valid_range(__first, __last);
3614
3615 for (; __first != __last; ++__first, ++__result)
3616 if (*__first == __old_value)
3617 *__result = __new_value;
3618 else
3619 *__result = *__first;
3620 return __result;
3621 }
3622
3623 /**
3624 * @brief Copy a sequence, replacing each value for which a predicate
3625 * returns true with another value.
3626 * @param first An input iterator.
3627 * @param last An input iterator.
3628 * @param result An output iterator.
3629 * @param pred A predicate.
3630 * @param new_value The replacement value.
3631 * @return The end of the output sequence, @p result+(last-first).
3632 *
3633 * Copies each element in the range @p [first,last) to the range
3634 * @p [result,result+(last-first)) replacing elements for which
3635 * @p pred returns true with @p new_value.
3636 */
3637 template<typename _InputIterator, typename _OutputIterator,
3638 typename _Predicate, typename _Tp>
3639 _OutputIterator
3640 replace_copy_if(_InputIterator __first, _InputIterator __last,
3641 _OutputIterator __result,
3642 _Predicate __pred, const _Tp& __new_value)
3643 {
3644 // concept requirements
3645 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3646 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
3647 typename iterator_traits<_InputIterator>::value_type>)
3648 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
3649 typename iterator_traits<_InputIterator>::value_type>)
3650 __glibcxx_requires_valid_range(__first, __last);
3651
3652 for (; __first != __last; ++__first, ++__result)
3653 if (__pred(*__first))
3654 *__result = __new_value;
3655 else
3656 *__result = *__first;
3657 return __result;
3658 }
3659
3660 _GLIBCXX_END_NAMESPACE
3661
3662 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_P)
3663
3664 /**
3665 * @brief Apply a function to every element of a sequence.
3666 * @param first An input iterator.
3667 * @param last An input iterator.
3668 * @param f A unary function object.
3669 * @return @p f.
3670 *
3671 * Applies the function object @p f to each element in the range
3672 * @p [first,last). @p f must not modify the order of the sequence.
3673 * If @p f has a return value it is ignored.
3674 */
3675 template<typename _InputIterator, typename _Function>
3676 _Function
3677 for_each(_InputIterator __first, _InputIterator __last, _Function __f)
3678 {
3679 // concept requirements
3680 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3681 __glibcxx_requires_valid_range(__first, __last);
3682 for (; __first != __last; ++__first)
3683 __f(*__first);
3684 return __f;
3685 }
3686
3687 /**
3688 * @brief Find the first occurrence of a value in a sequence.
3689 * @param first An input iterator.
3690 * @param last An input iterator.
3691 * @param val The value to find.
3692 * @return The first iterator @c i in the range @p [first,last)
3693 * such that @c *i == @p val, or @p last if no such iterator exists.
3694 */
3695 template<typename _InputIterator, typename _Tp>
3696 inline _InputIterator
3697 find(_InputIterator __first, _InputIterator __last,
3698 const _Tp& __val)
3699 {
3700 // concept requirements
3701 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3702 __glibcxx_function_requires(_EqualOpConcept<
3703 typename iterator_traits<_InputIterator>::value_type, _Tp>)
3704 __glibcxx_requires_valid_range(__first, __last);
3705 return std::__find(__first, __last, __val,
3706 std::__iterator_category(__first));
3707 }
3708
3709 /**
3710 * @brief Find the first element in a sequence for which a
3711 * predicate is true.
3712 * @param first An input iterator.
3713 * @param last An input iterator.
3714 * @param pred A predicate.
3715 * @return The first iterator @c i in the range @p [first,last)
3716 * such that @p pred(*i) is true, or @p last if no such iterator exists.
3717 */
3718 template<typename _InputIterator, typename _Predicate>
3719 inline _InputIterator
3720 find_if(_InputIterator __first, _InputIterator __last,
3721 _Predicate __pred)
3722 {
3723 // concept requirements
3724 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3725 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
3726 typename iterator_traits<_InputIterator>::value_type>)
3727 __glibcxx_requires_valid_range(__first, __last);
3728 return std::__find_if(__first, __last, __pred,
3729 std::__iterator_category(__first));
3730 }
3731
3732 /**
3733 * @brief Find element from a set in a sequence.
3734 * @param first1 Start of range to search.
3735 * @param last1 End of range to search.
3736 * @param first2 Start of match candidates.
3737 * @param last2 End of match candidates.
3738 * @return The first iterator @c i in the range
3739 * @p [first1,last1) such that @c *i == @p *(i2) such that i2 is an
3740 * interator in [first2,last2), or @p last1 if no such iterator exists.
3741 *
3742 * Searches the range @p [first1,last1) for an element that is equal to
3743 * some element in the range [first2,last2). If found, returns an iterator
3744 * in the range [first1,last1), otherwise returns @p last1.
3745 */
3746 template<typename _InputIterator, typename _ForwardIterator>
3747 _InputIterator
3748 find_first_of(_InputIterator __first1, _InputIterator __last1,
3749 _ForwardIterator __first2, _ForwardIterator __last2)
3750 {
3751 // concept requirements
3752 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3753 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3754 __glibcxx_function_requires(_EqualOpConcept<
3755 typename iterator_traits<_InputIterator>::value_type,
3756 typename iterator_traits<_ForwardIterator>::value_type>)
3757 __glibcxx_requires_valid_range(__first1, __last1);
3758 __glibcxx_requires_valid_range(__first2, __last2);
3759
3760 for (; __first1 != __last1; ++__first1)
3761 for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter)
3762 if (*__first1 == *__iter)
3763 return __first1;
3764 return __last1;
3765 }
3766
3767 /**
3768 * @brief Find element from a set in a sequence using a predicate.
3769 * @param first1 Start of range to search.
3770 * @param last1 End of range to search.
3771 * @param first2 Start of match candidates.
3772 * @param last2 End of match candidates.
3773 * @param comp Predicate to use.
3774 * @return The first iterator @c i in the range
3775 * @p [first1,last1) such that @c comp(*i, @p *(i2)) is true and i2 is an
3776 * interator in [first2,last2), or @p last1 if no such iterator exists.
3777 *
3778
3779 * Searches the range @p [first1,last1) for an element that is
3780 * equal to some element in the range [first2,last2). If found,
3781 * returns an iterator in the range [first1,last1), otherwise
3782 * returns @p last1.
3783 */
3784 template<typename _InputIterator, typename _ForwardIterator,
3785 typename _BinaryPredicate>
3786 _InputIterator
3787 find_first_of(_InputIterator __first1, _InputIterator __last1,
3788 _ForwardIterator __first2, _ForwardIterator __last2,
3789 _BinaryPredicate __comp)
3790 {
3791 // concept requirements
3792 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3793 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3794 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
3795 typename iterator_traits<_InputIterator>::value_type,
3796 typename iterator_traits<_ForwardIterator>::value_type>)
3797 __glibcxx_requires_valid_range(__first1, __last1);
3798 __glibcxx_requires_valid_range(__first2, __last2);
3799
3800 for (; __first1 != __last1; ++__first1)
3801 for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter)
3802 if (__comp(*__first1, *__iter))
3803 return __first1;
3804 return __last1;
3805 }
3806
3807 /**
3808 * @brief Find two adjacent values in a sequence that are equal.
3809 * @param first A forward iterator.
3810 * @param last A forward iterator.
3811 * @return The first iterator @c i such that @c i and @c i+1 are both
3812 * valid iterators in @p [first,last) and such that @c *i == @c *(i+1),
3813 * or @p last if no such iterator exists.
3814 */
3815 template<typename _ForwardIterator>
3816 _ForwardIterator
3817 adjacent_find(_ForwardIterator __first, _ForwardIterator __last)
3818 {
3819 // concept requirements
3820 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3821 __glibcxx_function_requires(_EqualityComparableConcept<
3822 typename iterator_traits<_ForwardIterator>::value_type>)
3823 __glibcxx_requires_valid_range(__first, __last);
3824 if (__first == __last)
3825 return __last;
3826 _ForwardIterator __next = __first;
3827 while(++__next != __last)
3828 {
3829 if (*__first == *__next)
3830 return __first;
3831 __first = __next;
3832 }
3833 return __last;
3834 }
3835
3836 /**
3837 * @brief Find two adjacent values in a sequence using a predicate.
3838 * @param first A forward iterator.
3839 * @param last A forward iterator.
3840 * @param binary_pred A binary predicate.
3841 * @return The first iterator @c i such that @c i and @c i+1 are both
3842 * valid iterators in @p [first,last) and such that
3843 * @p binary_pred(*i,*(i+1)) is true, or @p last if no such iterator
3844 * exists.
3845 */
3846 template<typename _ForwardIterator, typename _BinaryPredicate>
3847 _ForwardIterator
3848 adjacent_find(_ForwardIterator __first, _ForwardIterator __last,
3849 _BinaryPredicate __binary_pred)
3850 {
3851 // concept requirements
3852 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
3853 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
3854 typename iterator_traits<_ForwardIterator>::value_type,
3855 typename iterator_traits<_ForwardIterator>::value_type>)
3856 __glibcxx_requires_valid_range(__first, __last);
3857 if (__first == __last)
3858 return __last;
3859 _ForwardIterator __next = __first;
3860 while(++__next != __last)
3861 {
3862 if (__binary_pred(*__first, *__next))
3863 return __first;
3864 __first = __next;
3865 }
3866 return __last;
3867 }
3868
3869 /**
3870 * @brief Count the number of copies of a value in a sequence.
3871 * @param first An input iterator.
3872 * @param last An input iterator.
3873 * @param value The value to be counted.
3874 * @return The number of iterators @c i in the range @p [first,last)
3875 * for which @c *i == @p value
3876 */
3877 template<typename _InputIterator, typename _Tp>
3878 typename iterator_traits<_InputIterator>::difference_type
3879 count(_InputIterator __first, _InputIterator __last, const _Tp& __value)
3880 {
3881 // concept requirements
3882 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3883 __glibcxx_function_requires(_EqualOpConcept<
3884 typename iterator_traits<_InputIterator>::value_type, _Tp>)
3885 __glibcxx_requires_valid_range(__first, __last);
3886 typename iterator_traits<_InputIterator>::difference_type __n = 0;
3887 for (; __first != __last; ++__first)
3888 if (*__first == __value)
3889 ++__n;
3890 return __n;
3891 }
3892
3893 /**
3894 * @brief Count the elements of a sequence for which a predicate is true.
3895 * @param first An input iterator.
3896 * @param last An input iterator.
3897 * @param pred A predicate.
3898 * @return The number of iterators @c i in the range @p [first,last)
3899 * for which @p pred(*i) is true.
3900 */
3901 template<typename _InputIterator, typename _Predicate>
3902 typename iterator_traits<_InputIterator>::difference_type
3903 count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
3904 {
3905 // concept requirements
3906 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
3907 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
3908 typename iterator_traits<_InputIterator>::value_type>)
3909 __glibcxx_requires_valid_range(__first, __last);
3910 typename iterator_traits<_InputIterator>::difference_type __n = 0;
3911 for (; __first != __last; ++__first)
3912 if (__pred(*__first))
3913 ++__n;
3914 return __n;
3915 }
3916
3917 /**
3918 * @brief Search a sequence for a matching sub-sequence.
3919 * @param first1 A forward iterator.
3920 * @param last1 A forward iterator.
3921 * @param first2 A forward iterator.
3922 * @param last2 A forward iterator.
3923 * @return The first iterator @c i in the range
3924 * @p [first1,last1-(last2-first2)) such that @c *(i+N) == @p *(first2+N)
3925 * for each @c N in the range @p [0,last2-first2), or @p last1 if no
3926 * such iterator exists.
3927 *
3928 * Searches the range @p [first1,last1) for a sub-sequence that compares
3929 * equal value-by-value with the sequence given by @p [first2,last2) and
3930 * returns an iterator to the first element of the sub-sequence, or
3931 * @p last1 if the sub-sequence is not found.
3932 *
3933 * Because the sub-sequence must lie completely within the range
3934 * @p [first1,last1) it must start at a position less than
3935 * @p last1-(last2-first2) where @p last2-first2 is the length of the
3936 * sub-sequence.
3937 * This means that the returned iterator @c i will be in the range
3938 * @p [first1,last1-(last2-first2))
3939 */
3940 template<typename _ForwardIterator1, typename _ForwardIterator2>
3941 _ForwardIterator1
3942 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
3943 _ForwardIterator2 __first2, _ForwardIterator2 __last2)
3944 {
3945 // concept requirements
3946 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
3947 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
3948 __glibcxx_function_requires(_EqualOpConcept<
3949 typename iterator_traits<_ForwardIterator1>::value_type,
3950 typename iterator_traits<_ForwardIterator2>::value_type>)
3951 __glibcxx_requires_valid_range(__first1, __last1);
3952 __glibcxx_requires_valid_range(__first2, __last2);
3953
3954 // Test for empty ranges
3955 if (__first1 == __last1 || __first2 == __last2)
3956 return __first1;
3957
3958 // Test for a pattern of length 1.
3959 _ForwardIterator2 __p1(__first2);
3960 if (++__p1 == __last2)
3961 return _GLIBCXX_STD_P::find(__first1, __last1, *__first2);
3962
3963 // General case.
3964 _ForwardIterator2 __p;
3965 _ForwardIterator1 __current = __first1;
3966
3967 for (;;)
3968 {
3969 __first1 = _GLIBCXX_STD_P::find(__first1, __last1, *__first2);
3970 if (__first1 == __last1)
3971 return __last1;
3972
3973 __p = __p1;
3974 __current = __first1;
3975 if (++__current == __last1)
3976 return __last1;
3977
3978 while (*__current == *__p)
3979 {
3980 if (++__p == __last2)
3981 return __first1;
3982 if (++__current == __last1)
3983 return __last1;
3984 }
3985 ++__first1;
3986 }
3987 return __first1;
3988 }
3989
3990 /**
3991 * @brief Search a sequence for a matching sub-sequence using a predicate.
3992 * @param first1 A forward iterator.
3993 * @param last1 A forward iterator.
3994 * @param first2 A forward iterator.
3995 * @param last2 A forward iterator.
3996 * @param predicate A binary predicate.
3997 * @return The first iterator @c i in the range
3998 * @p [first1,last1-(last2-first2)) such that
3999 * @p predicate(*(i+N),*(first2+N)) is true for each @c N in the range
4000 * @p [0,last2-first2), or @p last1 if no such iterator exists.
4001 *
4002 * Searches the range @p [first1,last1) for a sub-sequence that compares
4003 * equal value-by-value with the sequence given by @p [first2,last2),
4004 * using @p predicate to determine equality, and returns an iterator
4005 * to the first element of the sub-sequence, or @p last1 if no such
4006 * iterator exists.
4007 *
4008 * @see search(_ForwardIter1, _ForwardIter1, _ForwardIter2, _ForwardIter2)
4009 */
4010 template<typename _ForwardIterator1, typename _ForwardIterator2,
4011 typename _BinaryPredicate>
4012 _ForwardIterator1
4013 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
4014 _ForwardIterator2 __first2, _ForwardIterator2 __last2,
4015 _BinaryPredicate __predicate)
4016 {
4017 // concept requirements
4018 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>)
4019 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>)
4020 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
4021 typename iterator_traits<_ForwardIterator1>::value_type,
4022 typename iterator_traits<_ForwardIterator2>::value_type>)
4023 __glibcxx_requires_valid_range(__first1, __last1);
4024 __glibcxx_requires_valid_range(__first2, __last2);
4025
4026 // Test for empty ranges
4027 if (__first1 == __last1 || __first2 == __last2)
4028 return __first1;
4029
4030 // Test for a pattern of length 1.
4031 _ForwardIterator2 __p1(__first2);
4032 if (++__p1 == __last2)
4033 {
4034 while (__first1 != __last1
4035 && !bool(__predicate(*__first1, *__first2)))
4036 ++__first1;
4037 return __first1;
4038 }
4039
4040 // General case.
4041 _ForwardIterator2 __p;
4042 _ForwardIterator1 __current = __first1;
4043
4044 for (;;)
4045 {
4046 while (__first1 != __last1
4047 && !bool(__predicate(*__first1, *__first2)))
4048 ++__first1;
4049 if (__first1 == __last1)
4050 return __last1;
4051
4052 __p = __p1;
4053 __current = __first1;
4054 if (++__current == __last1)
4055 return __last1;
4056
4057 while (__predicate(*__current, *__p))
4058 {
4059 if (++__p == __last2)
4060 return __first1;
4061 if (++__current == __last1)
4062 return __last1;
4063 }
4064 ++__first1;
4065 }
4066 return __first1;
4067 }
4068
4069
4070 /**
4071 * @brief Search a sequence for a number of consecutive values.
4072 * @param first A forward iterator.
4073 * @param last A forward iterator.
4074 * @param count The number of consecutive values.
4075 * @param val The value to find.
4076 * @return The first iterator @c i in the range @p [first,last-count)
4077 * such that @c *(i+N) == @p val for each @c N in the range @p [0,count),
4078 * or @p last if no such iterator exists.
4079 *
4080 * Searches the range @p [first,last) for @p count consecutive elements
4081 * equal to @p val.
4082 */
4083 template<typename _ForwardIterator, typename _Integer, typename _Tp>
4084 _ForwardIterator
4085 search_n(_ForwardIterator __first, _ForwardIterator __last,
4086 _Integer __count, const _Tp& __val)
4087 {
4088 // concept requirements
4089 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
4090 __glibcxx_function_requires(_EqualOpConcept<
4091 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
4092 __glibcxx_requires_valid_range(__first, __last);
4093
4094 if (__count <= 0)
4095 return __first;
4096 if (__count == 1)
4097 return _GLIBCXX_STD_P::find(__first, __last, __val);
4098 return std::__search_n(__first, __last, __count, __val,
4099 std::__iterator_category(__first));
4100 }
4101
4102
4103 /**
4104 * @brief Search a sequence for a number of consecutive values using a
4105 * predicate.
4106 * @param first A forward iterator.
4107 * @param last A forward iterator.
4108 * @param count The number of consecutive values.
4109 * @param val The value to find.
4110 * @param binary_pred A binary predicate.
4111 * @return The first iterator @c i in the range @p [first,last-count)
4112 * such that @p binary_pred(*(i+N),val) is true for each @c N in the
4113 * range @p [0,count), or @p last if no such iterator exists.
4114 *
4115 * Searches the range @p [first,last) for @p count consecutive elements
4116 * for which the predicate returns true.
4117 */
4118 template<typename _ForwardIterator, typename _Integer, typename _Tp,
4119 typename _BinaryPredicate>
4120 _ForwardIterator
4121 search_n(_ForwardIterator __first, _ForwardIterator __last,
4122 _Integer __count, const _Tp& __val,
4123 _BinaryPredicate __binary_pred)
4124 {
4125 // concept requirements
4126 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
4127 __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate,
4128 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
4129 __glibcxx_requires_valid_range(__first, __last);
4130
4131 if (__count <= 0)
4132 return __first;
4133 if (__count == 1)
4134 {
4135 while (__first != __last && !bool(__binary_pred(*__first, __val)))
4136 ++__first;
4137 return __first;
4138 }
4139 return std::__search_n(__first, __last, __count, __val, __binary_pred,
4140 std::__iterator_category(__first));
4141 }
4142
4143
4144 /**
4145 * @brief Perform an operation on a sequence.
4146 * @param first An input iterator.
4147 * @param last An input iterator.
4148 * @param result An output iterator.
4149 * @param unary_op A unary operator.
4150 * @return An output iterator equal to @p result+(last-first).
4151 *
4152 * Applies the operator to each element in the input range and assigns
4153 * the results to successive elements of the output sequence.
4154 * Evaluates @p *(result+N)=unary_op(*(first+N)) for each @c N in the
4155 * range @p [0,last-first).
4156 *
4157 * @p unary_op must not alter its argument.
4158 */
4159 template<typename _InputIterator, typename _OutputIterator,
4160 typename _UnaryOperation>
4161 _OutputIterator
4162 transform(_InputIterator __first, _InputIterator __last,
4163 _OutputIterator __result, _UnaryOperation __unary_op)
4164 {
4165 // concept requirements
4166 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
4167 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4168 // "the type returned by a _UnaryOperation"
4169 __typeof__(__unary_op(*__first))>)
4170 __glibcxx_requires_valid_range(__first, __last);
4171
4172 for (; __first != __last; ++__first, ++__result)
4173 *__result = __unary_op(*__first);
4174 return __result;
4175 }
4176
4177 /**
4178 * @brief Perform an operation on corresponding elements of two sequences.
4179 * @param first1 An input iterator.
4180 * @param last1 An input iterator.
4181 * @param first2 An input iterator.
4182 * @param result An output iterator.
4183 * @param binary_op A binary operator.
4184 * @return An output iterator equal to @p result+(last-first).
4185 *
4186 * Applies the operator to the corresponding elements in the two
4187 * input ranges and assigns the results to successive elements of the
4188 * output sequence.
4189 * Evaluates @p *(result+N)=binary_op(*(first1+N),*(first2+N)) for each
4190 * @c N in the range @p [0,last1-first1).
4191 *
4192 * @p binary_op must not alter either of its arguments.
4193 */
4194 template<typename _InputIterator1, typename _InputIterator2,
4195 typename _OutputIterator, typename _BinaryOperation>
4196 _OutputIterator
4197 transform(_InputIterator1 __first1, _InputIterator1 __last1,
4198 _InputIterator2 __first2, _OutputIterator __result,
4199 _BinaryOperation __binary_op)
4200 {
4201 // concept requirements
4202 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4203 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4204 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4205 // "the type returned by a _BinaryOperation"
4206 __typeof__(__binary_op(*__first1,*__first2))>)
4207 __glibcxx_requires_valid_range(__first1, __last1);
4208
4209 for (; __first1 != __last1; ++__first1, ++__first2, ++__result)
4210 *__result = __binary_op(*__first1, *__first2);
4211 return __result;
4212 }
4213
4214 /**
4215 * @brief Replace each occurrence of one value in a sequence with another
4216 * value.
4217 * @param first A forward iterator.
4218 * @param last A forward iterator.
4219 * @param old_value The value to be replaced.
4220 * @param new_value The replacement value.
4221 * @return replace() returns no value.
4222 *
4223 * For each iterator @c i in the range @p [first,last) if @c *i ==
4224 * @p old_value then the assignment @c *i = @p new_value is performed.
4225 */
4226 template<typename _ForwardIterator, typename _Tp>
4227 void
4228 replace(_ForwardIterator __first, _ForwardIterator __last,
4229 const _Tp& __old_value, const _Tp& __new_value)
4230 {
4231 // concept requirements
4232 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
4233 _ForwardIterator>)
4234 __glibcxx_function_requires(_EqualOpConcept<
4235 typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
4236 __glibcxx_function_requires(_ConvertibleConcept<_Tp,
4237 typename iterator_traits<_ForwardIterator>::value_type>)
4238 __glibcxx_requires_valid_range(__first, __last);
4239
4240 for (; __first != __last; ++__first)
4241 if (*__first == __old_value)
4242 *__first = __new_value;
4243 }
4244
4245 /**
4246 * @brief Replace each value in a sequence for which a predicate returns
4247 * true with another value.
4248 * @param first A forward iterator.
4249 * @param last A forward iterator.
4250 * @param pred A predicate.
4251 * @param new_value The replacement value.
4252 * @return replace_if() returns no value.
4253 *
4254 * For each iterator @c i in the range @p [first,last) if @p pred(*i)
4255 * is true then the assignment @c *i = @p new_value is performed.
4256 */
4257 template<typename _ForwardIterator, typename _Predicate, typename _Tp>
4258 void
4259 replace_if(_ForwardIterator __first, _ForwardIterator __last,
4260 _Predicate __pred, const _Tp& __new_value)
4261 {
4262 // concept requirements
4263 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
4264 _ForwardIterator>)
4265 __glibcxx_function_requires(_ConvertibleConcept<_Tp,
4266 typename iterator_traits<_ForwardIterator>::value_type>)
4267 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
4268 typename iterator_traits<_ForwardIterator>::value_type>)
4269 __glibcxx_requires_valid_range(__first, __last);
4270
4271 for (; __first != __last; ++__first)
4272 if (__pred(*__first))
4273 *__first = __new_value;
4274 }
4275
4276 /**
4277 * @brief Assign the result of a function object to each value in a
4278 * sequence.
4279 * @param first A forward iterator.
4280 * @param last A forward iterator.
4281 * @param gen A function object taking no arguments and returning
4282 * std::iterator_traits<_ForwardIterator>::value_type
4283 * @return generate() returns no value.
4284 *
4285 * Performs the assignment @c *i = @p gen() for each @c i in the range
4286 * @p [first,last).
4287 */
4288 template<typename _ForwardIterator, typename _Generator>
4289 void
4290 generate(_ForwardIterator __first, _ForwardIterator __last,
4291 _Generator __gen)
4292 {
4293 // concept requirements
4294 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
4295 __glibcxx_function_requires(_GeneratorConcept<_Generator,
4296 typename iterator_traits<_ForwardIterator>::value_type>)
4297 __glibcxx_requires_valid_range(__first, __last);
4298
4299 for (; __first != __last; ++__first)
4300 *__first = __gen();
4301 }
4302
4303 /**
4304 * @brief Assign the result of a function object to each value in a
4305 * sequence.
4306 * @param first A forward iterator.
4307 * @param n The length of the sequence.
4308 * @param gen A function object taking no arguments and returning
4309 * std::iterator_traits<_ForwardIterator>::value_type
4310 * @return The end of the sequence, @p first+n
4311 *
4312 * Performs the assignment @c *i = @p gen() for each @c i in the range
4313 * @p [first,first+n).
4314 */
4315 template<typename _OutputIterator, typename _Size, typename _Generator>
4316 _OutputIterator
4317 generate_n(_OutputIterator __first, _Size __n, _Generator __gen)
4318 {
4319 // concept requirements
4320 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4321 // "the type returned by a _Generator"
4322 __typeof__(__gen())>)
4323
4324 for (; __n > 0; --__n, ++__first)
4325 *__first = __gen();
4326 return __first;
4327 }
4328
4329
4330 /**
4331 * @brief Copy a sequence, removing consecutive duplicate values.
4332 * @param first An input iterator.
4333 * @param last An input iterator.
4334 * @param result An output iterator.
4335 * @return An iterator designating the end of the resulting sequence.
4336 *
4337 * Copies each element in the range @p [first,last) to the range
4338 * beginning at @p result, except that only the first element is copied
4339 * from groups of consecutive elements that compare equal.
4340 * unique_copy() is stable, so the relative order of elements that are
4341 * copied is unchanged.
4342 *
4343 * @if maint
4344 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4345 * DR 241. Does unique_copy() require CopyConstructible and Assignable?
4346 *
4347 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4348 * DR 538. 241 again: Does unique_copy() require CopyConstructible and
4349 * Assignable?
4350 * @endif
4351 */
4352 template<typename _InputIterator, typename _OutputIterator>
4353 inline _OutputIterator
4354 unique_copy(_InputIterator __first, _InputIterator __last,
4355 _OutputIterator __result)
4356 {
4357 // concept requirements
4358 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
4359 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4360 typename iterator_traits<_InputIterator>::value_type>)
4361 __glibcxx_function_requires(_EqualityComparableConcept<
4362 typename iterator_traits<_InputIterator>::value_type>)
4363 __glibcxx_requires_valid_range(__first, __last);
4364
4365 if (__first == __last)
4366 return __result;
4367 return std::__unique_copy(__first, __last, __result,
4368 std::__iterator_category(__first),
4369 std::__iterator_category(__result));
4370 }
4371
4372 /**
4373 * @brief Copy a sequence, removing consecutive values using a predicate.
4374 * @param first An input iterator.
4375 * @param last An input iterator.
4376 * @param result An output iterator.
4377 * @param binary_pred A binary predicate.
4378 * @return An iterator designating the end of the resulting sequence.
4379 *
4380 * Copies each element in the range @p [first,last) to the range
4381 * beginning at @p result, except that only the first element is copied
4382 * from groups of consecutive elements for which @p binary_pred returns
4383 * true.
4384 * unique_copy() is stable, so the relative order of elements that are
4385 * copied is unchanged.
4386 *
4387 * @if maint
4388 * _GLIBCXX_RESOLVE_LIB_DEFECTS
4389 * DR 241. Does unique_copy() require CopyConstructible and Assignable?
4390 * @endif
4391 */
4392 template<typename _InputIterator, typename _OutputIterator,
4393 typename _BinaryPredicate>
4394 inline _OutputIterator
4395 unique_copy(_InputIterator __first, _InputIterator __last,
4396 _OutputIterator __result,
4397 _BinaryPredicate __binary_pred)
4398 {
4399 // concept requirements -- predicates checked later
4400 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
4401 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4402 typename iterator_traits<_InputIterator>::value_type>)
4403 __glibcxx_requires_valid_range(__first, __last);
4404
4405 if (__first == __last)
4406 return __result;
4407 return std::__unique_copy(__first, __last, __result, __binary_pred,
4408 std::__iterator_category(__first),
4409 std::__iterator_category(__result));
4410 }
4411
4412
4413 /**
4414 * @brief Randomly shuffle the elements of a sequence.
4415 * @param first A forward iterator.
4416 * @param last A forward iterator.
4417 * @return Nothing.
4418 *
4419 * Reorder the elements in the range @p [first,last) using a random
4420 * distribution, so that every possible ordering of the sequence is
4421 * equally likely.
4422 */
4423 template<typename _RandomAccessIterator>
4424 inline void
4425 random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
4426 {
4427 // concept requirements
4428 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4429 _RandomAccessIterator>)
4430 __glibcxx_requires_valid_range(__first, __last);
4431
4432 if (__first != __last)
4433 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
4434 std::iter_swap(__i, __first + (std::rand() % ((__i - __first) + 1)));
4435 }
4436
4437 /**
4438 * @brief Shuffle the elements of a sequence using a random number
4439 * generator.
4440 * @param first A forward iterator.
4441 * @param last A forward iterator.
4442 * @param rand The RNG functor or function.
4443 * @return Nothing.
4444 *
4445 * Reorders the elements in the range @p [first,last) using @p rand to
4446 * provide a random distribution. Calling @p rand(N) for a positive
4447 * integer @p N should return a randomly chosen integer from the
4448 * range [0,N).
4449 */
4450 template<typename _RandomAccessIterator, typename _RandomNumberGenerator>
4451 void
4452 random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
4453 _RandomNumberGenerator& __rand)
4454 {
4455 // concept requirements
4456 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4457 _RandomAccessIterator>)
4458 __glibcxx_requires_valid_range(__first, __last);
4459
4460 if (__first == __last)
4461 return;
4462 for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
4463 std::iter_swap(__i, __first + __rand((__i - __first) + 1));
4464 }
4465
4466
4467 /**
4468 * @brief Move elements for which a predicate is true to the beginning
4469 * of a sequence.
4470 * @param first A forward iterator.
4471 * @param last A forward iterator.
4472 * @param pred A predicate functor.
4473 * @return An iterator @p middle such that @p pred(i) is true for each
4474 * iterator @p i in the range @p [first,middle) and false for each @p i
4475 * in the range @p [middle,last).
4476 *
4477 * @p pred must not modify its operand. @p partition() does not preserve
4478 * the relative ordering of elements in each group, use
4479 * @p stable_partition() if this is needed.
4480 */
4481 template<typename _ForwardIterator, typename _Predicate>
4482 inline _ForwardIterator
4483 partition(_ForwardIterator __first, _ForwardIterator __last,
4484 _Predicate __pred)
4485 {
4486 // concept requirements
4487 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
4488 _ForwardIterator>)
4489 __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
4490 typename iterator_traits<_ForwardIterator>::value_type>)
4491 __glibcxx_requires_valid_range(__first, __last);
4492
4493 return std::__partition(__first, __last, __pred,
4494 std::__iterator_category(__first));
4495 }
4496
4497
4498
4499 /**
4500 * @brief Sort the smallest elements of a sequence.
4501 * @param first An iterator.
4502 * @param middle Another iterator.
4503 * @param last Another iterator.
4504 * @return Nothing.
4505 *
4506 * Sorts the smallest @p (middle-first) elements in the range
4507 * @p [first,last) and moves them to the range @p [first,middle). The
4508 * order of the remaining elements in the range @p [middle,last) is
4509 * undefined.
4510 * After the sort if @p i and @j are iterators in the range
4511 * @p [first,middle) such that @i precedes @j and @k is an iterator in
4512 * the range @p [middle,last) then @p *j<*i and @p *k<*i are both false.
4513 */
4514 template<typename _RandomAccessIterator>
4515 inline void
4516 partial_sort(_RandomAccessIterator __first,
4517 _RandomAccessIterator __middle,
4518 _RandomAccessIterator __last)
4519 {
4520 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4521 _ValueType;
4522
4523 // concept requirements
4524 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4525 _RandomAccessIterator>)
4526 __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
4527 __glibcxx_requires_valid_range(__first, __middle);
4528 __glibcxx_requires_valid_range(__middle, __last);
4529
4530 std::__heap_select(__first, __middle, __last);
4531 std::sort_heap(__first, __middle);
4532 }
4533
4534 /**
4535 * @brief Sort the smallest elements of a sequence using a predicate
4536 * for comparison.
4537 * @param first An iterator.
4538 * @param middle Another iterator.
4539 * @param last Another iterator.
4540 * @param comp A comparison functor.
4541 * @return Nothing.
4542 *
4543 * Sorts the smallest @p (middle-first) elements in the range
4544 * @p [first,last) and moves them to the range @p [first,middle). The
4545 * order of the remaining elements in the range @p [middle,last) is
4546 * undefined.
4547 * After the sort if @p i and @j are iterators in the range
4548 * @p [first,middle) such that @i precedes @j and @k is an iterator in
4549 * the range @p [middle,last) then @p *comp(j,*i) and @p comp(*k,*i)
4550 * are both false.
4551 */
4552 template<typename _RandomAccessIterator, typename _Compare>
4553 inline void
4554 partial_sort(_RandomAccessIterator __first,
4555 _RandomAccessIterator __middle,
4556 _RandomAccessIterator __last,
4557 _Compare __comp)
4558 {
4559 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4560 _ValueType;
4561
4562 // concept requirements
4563 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4564 _RandomAccessIterator>)
4565 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4566 _ValueType, _ValueType>)
4567 __glibcxx_requires_valid_range(__first, __middle);
4568 __glibcxx_requires_valid_range(__middle, __last);
4569
4570 std::__heap_select(__first, __middle, __last, __comp);
4571 std::sort_heap(__first, __middle, __comp);
4572 }
4573
4574 /**
4575 * @brief Sort a sequence just enough to find a particular position.
4576 * @param first An iterator.
4577 * @param nth Another iterator.
4578 * @param last Another iterator.
4579 * @return Nothing.
4580 *
4581 * Rearranges the elements in the range @p [first,last) so that @p *nth
4582 * is the same element that would have been in that position had the
4583 * whole sequence been sorted.
4584 * whole sequence been sorted. The elements either side of @p *nth are
4585 * not completely sorted, but for any iterator @i in the range
4586 * @p [first,nth) and any iterator @j in the range @p [nth,last) it
4587 * holds that @p *j<*i is false.
4588 */
4589 template<typename _RandomAccessIterator>
4590 inline void
4591 nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth,
4592 _RandomAccessIterator __last)
4593 {
4594 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4595 _ValueType;
4596
4597 // concept requirements
4598 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4599 _RandomAccessIterator>)
4600 __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
4601 __glibcxx_requires_valid_range(__first, __nth);
4602 __glibcxx_requires_valid_range(__nth, __last);
4603
4604 if (__first == __last || __nth == __last)
4605 return;
4606
4607 std::__introselect(__first, __nth, __last,
4608 std::__lg(__last - __first) * 2);
4609 }
4610
4611 /**
4612 * @brief Sort a sequence just enough to find a particular position
4613 * using a predicate for comparison.
4614 * @param first An iterator.
4615 * @param nth Another iterator.
4616 * @param last Another iterator.
4617 * @param comp A comparison functor.
4618 * @return Nothing.
4619 *
4620 * Rearranges the elements in the range @p [first,last) so that @p *nth
4621 * is the same element that would have been in that position had the
4622 * whole sequence been sorted. The elements either side of @p *nth are
4623 * not completely sorted, but for any iterator @i in the range
4624 * @p [first,nth) and any iterator @j in the range @p [nth,last) it
4625 * holds that @p comp(*j,*i) is false.
4626 */
4627 template<typename _RandomAccessIterator, typename _Compare>
4628 inline void
4629 nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth,
4630 _RandomAccessIterator __last, _Compare __comp)
4631 {
4632 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4633 _ValueType;
4634
4635 // concept requirements
4636 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4637 _RandomAccessIterator>)
4638 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4639 _ValueType, _ValueType>)
4640 __glibcxx_requires_valid_range(__first, __nth);
4641 __glibcxx_requires_valid_range(__nth, __last);
4642
4643 if (__first == __last || __nth == __last)
4644 return;
4645
4646 std::__introselect(__first, __nth, __last,
4647 std::__lg(__last - __first) * 2, __comp);
4648 }
4649
4650
4651 /**
4652 * @brief Sort the elements of a sequence.
4653 * @param first An iterator.
4654 * @param last Another iterator.
4655 * @return Nothing.
4656 *
4657 * Sorts the elements in the range @p [first,last) in ascending order,
4658 * such that @p *(i+1)<*i is false for each iterator @p i in the range
4659 * @p [first,last-1).
4660 *
4661 * The relative ordering of equivalent elements is not preserved, use
4662 * @p stable_sort() if this is needed.
4663 */
4664 template<typename _RandomAccessIterator>
4665 inline void
4666 sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
4667 {
4668 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4669 _ValueType;
4670
4671 // concept requirements
4672 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4673 _RandomAccessIterator>)
4674 __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
4675 __glibcxx_requires_valid_range(__first, __last);
4676
4677 if (__first != __last)
4678 {
4679 std::__introsort_loop(__first, __last,
4680 std::__lg(__last - __first) * 2);
4681 std::__final_insertion_sort(__first, __last);
4682 }
4683 }
4684
4685 /**
4686 * @brief Sort the elements of a sequence using a predicate for comparison.
4687 * @param first An iterator.
4688 * @param last Another iterator.
4689 * @param comp A comparison functor.
4690 * @return Nothing.
4691 *
4692 * Sorts the elements in the range @p [first,last) in ascending order,
4693 * such that @p comp(*(i+1),*i) is false for every iterator @p i in the
4694 * range @p [first,last-1).
4695 *
4696 * The relative ordering of equivalent elements is not preserved, use
4697 * @p stable_sort() if this is needed.
4698 */
4699 template<typename _RandomAccessIterator, typename _Compare>
4700 inline void
4701 sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
4702 _Compare __comp)
4703 {
4704 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4705 _ValueType;
4706
4707 // concept requirements
4708 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4709 _RandomAccessIterator>)
4710 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, _ValueType,
4711 _ValueType>)
4712 __glibcxx_requires_valid_range(__first, __last);
4713
4714 if (__first != __last)
4715 {
4716 std::__introsort_loop(__first, __last,
4717 std::__lg(__last - __first) * 2, __comp);
4718 std::__final_insertion_sort(__first, __last, __comp);
4719 }
4720 }
4721
4722 /**
4723 * @brief Merges two sorted ranges.
4724 * @param first1 An iterator.
4725 * @param first2 Another iterator.
4726 * @param last1 Another iterator.
4727 * @param last2 Another iterator.
4728 * @param result An iterator pointing to the end of the merged range.
4729 * @return An iterator pointing to the first element "not less
4730 * than" @a val.
4731 *
4732 * Merges the ranges [first1,last1) and [first2,last2) into the sorted range
4733 * [result, result + (last1-first1) + (last2-first2)). Both input ranges
4734 * must be sorted, and the output range must not overlap with either of
4735 * the input ranges. The sort is @e stable, that is, for equivalent
4736 * elements in the two ranges, elements from the first range will always
4737 * come before elements from the second.
4738 */
4739 template<typename _InputIterator1, typename _InputIterator2,
4740 typename _OutputIterator>
4741 _OutputIterator
4742 merge(_InputIterator1 __first1, _InputIterator1 __last1,
4743 _InputIterator2 __first2, _InputIterator2 __last2,
4744 _OutputIterator __result)
4745 {
4746 typedef typename iterator_traits<_InputIterator1>::value_type
4747 _ValueType1;
4748 typedef typename iterator_traits<_InputIterator2>::value_type
4749 _ValueType2;
4750
4751 // concept requirements
4752 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4753 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4754 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4755 _ValueType1>)
4756 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4757 _ValueType2>)
4758 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
4759 __glibcxx_requires_sorted(__first1, __last1);
4760 __glibcxx_requires_sorted(__first2, __last2);
4761
4762 while (__first1 != __last1 && __first2 != __last2)
4763 {
4764 if (*__first2 < *__first1)
4765 {
4766 *__result = *__first2;
4767 ++__first2;
4768 }
4769 else
4770 {
4771 *__result = *__first1;
4772 ++__first1;
4773 }
4774 ++__result;
4775 }
4776 return std::copy(__first2, __last2, std::copy(__first1, __last1,
4777 __result));
4778 }
4779
4780 /**
4781 * @brief Merges two sorted ranges.
4782 * @param first1 An iterator.
4783 * @param first2 Another iterator.
4784 * @param last1 Another iterator.
4785 * @param last2 Another iterator.
4786 * @param result An iterator pointing to the end of the merged range.
4787 * @param comp A functor to use for comparisons.
4788 * @return An iterator pointing to the first element "not less
4789 * than" @a val.
4790 *
4791 * Merges the ranges [first1,last1) and [first2,last2) into the sorted range
4792 * [result, result + (last1-first1) + (last2-first2)). Both input ranges
4793 * must be sorted, and the output range must not overlap with either of
4794 * the input ranges. The sort is @e stable, that is, for equivalent
4795 * elements in the two ranges, elements from the first range will always
4796 * come before elements from the second.
4797 *
4798 * The comparison function should have the same effects on ordering as
4799 * the function used for the initial sort.
4800 */
4801 template<typename _InputIterator1, typename _InputIterator2,
4802 typename _OutputIterator, typename _Compare>
4803 _OutputIterator
4804 merge(_InputIterator1 __first1, _InputIterator1 __last1,
4805 _InputIterator2 __first2, _InputIterator2 __last2,
4806 _OutputIterator __result, _Compare __comp)
4807 {
4808 typedef typename iterator_traits<_InputIterator1>::value_type
4809 _ValueType1;
4810 typedef typename iterator_traits<_InputIterator2>::value_type
4811 _ValueType2;
4812
4813 // concept requirements
4814 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4815 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4816 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4817 _ValueType1>)
4818 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4819 _ValueType2>)
4820 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4821 _ValueType2, _ValueType1>)
4822 __glibcxx_requires_sorted_pred(__first1, __last1, __comp);
4823 __glibcxx_requires_sorted_pred(__first2, __last2, __comp);
4824
4825 while (__first1 != __last1 && __first2 != __last2)
4826 {
4827 if (__comp(*__first2, *__first1))
4828 {
4829 *__result = *__first2;
4830 ++__first2;
4831 }
4832 else
4833 {
4834 *__result = *__first1;
4835 ++__first1;
4836 }
4837 ++__result;
4838 }
4839 return std::copy(__first2, __last2, std::copy(__first1, __last1,
4840 __result));
4841 }
4842
4843
4844 /**
4845 * @brief Sort the elements of a sequence, preserving the relative order
4846 * of equivalent elements.
4847 * @param first An iterator.
4848 * @param last Another iterator.
4849 * @return Nothing.
4850 *
4851 * Sorts the elements in the range @p [first,last) in ascending order,
4852 * such that @p *(i+1)<*i is false for each iterator @p i in the range
4853 * @p [first,last-1).
4854 *
4855 * The relative ordering of equivalent elements is preserved, so any two
4856 * elements @p x and @p y in the range @p [first,last) such that
4857 * @p x<y is false and @p y<x is false will have the same relative
4858 * ordering after calling @p stable_sort().
4859 */
4860 template<typename _RandomAccessIterator>
4861 inline void
4862 stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
4863 {
4864 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4865 _ValueType;
4866 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
4867 _DistanceType;
4868
4869 // concept requirements
4870 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4871 _RandomAccessIterator>)
4872 __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
4873 __glibcxx_requires_valid_range(__first, __last);
4874
4875 _Temporary_buffer<_RandomAccessIterator, _ValueType> __buf(__first,
4876 __last);
4877 if (__buf.begin() == 0)
4878 std::__inplace_stable_sort(__first, __last);
4879 else
4880 std::__stable_sort_adaptive(__first, __last, __buf.begin(),
4881 _DistanceType(__buf.size()));
4882 }
4883
4884 /**
4885 * @brief Sort the elements of a sequence using a predicate for comparison,
4886 * preserving the relative order of equivalent elements.
4887 * @param first An iterator.
4888 * @param last Another iterator.
4889 * @param comp A comparison functor.
4890 * @return Nothing.
4891 *
4892 * Sorts the elements in the range @p [first,last) in ascending order,
4893 * such that @p comp(*(i+1),*i) is false for each iterator @p i in the
4894 * range @p [first,last-1).
4895 *
4896 * The relative ordering of equivalent elements is preserved, so any two
4897 * elements @p x and @p y in the range @p [first,last) such that
4898 * @p comp(x,y) is false and @p comp(y,x) is false will have the same
4899 * relative ordering after calling @p stable_sort().
4900 */
4901 template<typename _RandomAccessIterator, typename _Compare>
4902 inline void
4903 stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
4904 _Compare __comp)
4905 {
4906 typedef typename iterator_traits<_RandomAccessIterator>::value_type
4907 _ValueType;
4908 typedef typename iterator_traits<_RandomAccessIterator>::difference_type
4909 _DistanceType;
4910
4911 // concept requirements
4912 __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
4913 _RandomAccessIterator>)
4914 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
4915 _ValueType,
4916 _ValueType>)
4917 __glibcxx_requires_valid_range(__first, __last);
4918
4919 _Temporary_buffer<_RandomAccessIterator, _ValueType> __buf(__first,
4920 __last);
4921 if (__buf.begin() == 0)
4922 std::__inplace_stable_sort(__first, __last, __comp);
4923 else
4924 std::__stable_sort_adaptive(__first, __last, __buf.begin(),
4925 _DistanceType(__buf.size()), __comp);
4926 }
4927
4928
4929 /**
4930 * @brief Return the union of two sorted ranges.
4931 * @param first1 Start of first range.
4932 * @param last1 End of first range.
4933 * @param first2 Start of second range.
4934 * @param last2 End of second range.
4935 * @return End of the output range.
4936 * @ingroup setoperations
4937 *
4938 * This operation iterates over both ranges, copying elements present in
4939 * each range in order to the output range. Iterators increment for each
4940 * range. When the current element of one range is less than the other,
4941 * that element is copied and the iterator advanced. If an element is
4942 * contained in both ranges, the element from the first range is copied and
4943 * both ranges advance. The output range may not overlap either input
4944 * range.
4945 */
4946 template<typename _InputIterator1, typename _InputIterator2,
4947 typename _OutputIterator>
4948 _OutputIterator
4949 set_union(_InputIterator1 __first1, _InputIterator1 __last1,
4950 _InputIterator2 __first2, _InputIterator2 __last2,
4951 _OutputIterator __result)
4952 {
4953 typedef typename iterator_traits<_InputIterator1>::value_type
4954 _ValueType1;
4955 typedef typename iterator_traits<_InputIterator2>::value_type
4956 _ValueType2;
4957
4958 // concept requirements
4959 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
4960 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
4961 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4962 _ValueType1>)
4963 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
4964 _ValueType2>)
4965 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
4966 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
4967 __glibcxx_requires_sorted(__first1, __last1);
4968 __glibcxx_requires_sorted(__first2, __last2);
4969
4970 while (__first1 != __last1 && __first2 != __last2)
4971 {
4972 if (*__first1 < *__first2)
4973 {
4974 *__result = *__first1;
4975 ++__first1;
4976 }
4977 else if (*__first2 < *__first1)
4978 {
4979 *__result = *__first2;
4980 ++__first2;
4981 }
4982 else
4983 {
4984 *__result = *__first1;
4985 ++__first1;
4986 ++__first2;
4987 }
4988 ++__result;
4989 }
4990 return std::copy(__first2, __last2, std::copy(__first1, __last1,
4991 __result));
4992 }
4993
4994 /**
4995 * @brief Return the union of two sorted ranges using a comparison functor.
4996 * @param first1 Start of first range.
4997 * @param last1 End of first range.
4998 * @param first2 Start of second range.
4999 * @param last2 End of second range.
5000 * @param comp The comparison functor.
5001 * @return End of the output range.
5002 * @ingroup setoperations
5003 *
5004 * This operation iterates over both ranges, copying elements present in
5005 * each range in order to the output range. Iterators increment for each
5006 * range. When the current element of one range is less than the other
5007 * according to @a comp, that element is copied and the iterator advanced.
5008 * If an equivalent element according to @a comp is contained in both
5009 * ranges, the element from the first range is copied and both ranges
5010 * advance. The output range may not overlap either input range.
5011 */
5012 template<typename _InputIterator1, typename _InputIterator2,
5013 typename _OutputIterator, typename _Compare>
5014 _OutputIterator
5015 set_union(_InputIterator1 __first1, _InputIterator1 __last1,
5016 _InputIterator2 __first2, _InputIterator2 __last2,
5017 _OutputIterator __result, _Compare __comp)
5018 {
5019 typedef typename iterator_traits<_InputIterator1>::value_type
5020 _ValueType1;
5021 typedef typename iterator_traits<_InputIterator2>::value_type
5022 _ValueType2;
5023
5024 // concept requirements
5025 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5026 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5027 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5028 _ValueType1>)
5029 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5030 _ValueType2>)
5031 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5032 _ValueType1, _ValueType2>)
5033 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5034 _ValueType2, _ValueType1>)
5035 __glibcxx_requires_sorted_pred(__first1, __last1, __comp);
5036 __glibcxx_requires_sorted_pred(__first2, __last2, __comp);
5037
5038 while (__first1 != __last1 && __first2 != __last2)
5039 {
5040 if (__comp(*__first1, *__first2))
5041 {
5042 *__result = *__first1;
5043 ++__first1;
5044 }
5045 else if (__comp(*__first2, *__first1))
5046 {
5047 *__result = *__first2;
5048 ++__first2;
5049 }
5050 else
5051 {
5052 *__result = *__first1;
5053 ++__first1;
5054 ++__first2;
5055 }
5056 ++__result;
5057 }
5058 return std::copy(__first2, __last2, std::copy(__first1, __last1,
5059 __result));
5060 }
5061
5062 /**
5063 * @brief Return the intersection of two sorted ranges.
5064 * @param first1 Start of first range.
5065 * @param last1 End of first range.
5066 * @param first2 Start of second range.
5067 * @param last2 End of second range.
5068 * @return End of the output range.
5069 * @ingroup setoperations
5070 *
5071 * This operation iterates over both ranges, copying elements present in
5072 * both ranges in order to the output range. Iterators increment for each
5073 * range. When the current element of one range is less than the other,
5074 * that iterator advances. If an element is contained in both ranges, the
5075 * element from the first range is copied and both ranges advance. The
5076 * output range may not overlap either input range.
5077 */
5078 template<typename _InputIterator1, typename _InputIterator2,
5079 typename _OutputIterator>
5080 _OutputIterator
5081 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5082 _InputIterator2 __first2, _InputIterator2 __last2,
5083 _OutputIterator __result)
5084 {
5085 typedef typename iterator_traits<_InputIterator1>::value_type
5086 _ValueType1;
5087 typedef typename iterator_traits<_InputIterator2>::value_type
5088 _ValueType2;
5089
5090 // concept requirements
5091 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5092 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5093 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5094 _ValueType1>)
5095 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
5096 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
5097 __glibcxx_requires_sorted(__first1, __last1);
5098 __glibcxx_requires_sorted(__first2, __last2);
5099
5100 while (__first1 != __last1 && __first2 != __last2)
5101 if (*__first1 < *__first2)
5102 ++__first1;
5103 else if (*__first2 < *__first1)
5104 ++__first2;
5105 else
5106 {
5107 *__result = *__first1;
5108 ++__first1;
5109 ++__first2;
5110 ++__result;
5111 }
5112 return __result;
5113 }
5114
5115 /**
5116 * @brief Return the intersection of two sorted ranges using comparison
5117 * functor.
5118 * @param first1 Start of first range.
5119 * @param last1 End of first range.
5120 * @param first2 Start of second range.
5121 * @param last2 End of second range.
5122 * @param comp The comparison functor.
5123 * @return End of the output range.
5124 * @ingroup setoperations
5125 *
5126 * This operation iterates over both ranges, copying elements present in
5127 * both ranges in order to the output range. Iterators increment for each
5128 * range. When the current element of one range is less than the other
5129 * according to @a comp, that iterator advances. If an element is
5130 * contained in both ranges according to @a comp, the element from the
5131 * first range is copied and both ranges advance. The output range may not
5132 * overlap either input range.
5133 */
5134 template<typename _InputIterator1, typename _InputIterator2,
5135 typename _OutputIterator, typename _Compare>
5136 _OutputIterator
5137 set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
5138 _InputIterator2 __first2, _InputIterator2 __last2,
5139 _OutputIterator __result, _Compare __comp)
5140 {
5141 typedef typename iterator_traits<_InputIterator1>::value_type
5142 _ValueType1;
5143 typedef typename iterator_traits<_InputIterator2>::value_type
5144 _ValueType2;
5145
5146 // concept requirements
5147 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5148 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5149 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5150 _ValueType1>)
5151 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5152 _ValueType1, _ValueType2>)
5153 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5154 _ValueType2, _ValueType1>)
5155 __glibcxx_requires_sorted_pred(__first1, __last1, __comp);
5156 __glibcxx_requires_sorted_pred(__first2, __last2, __comp);
5157
5158 while (__first1 != __last1 && __first2 != __last2)
5159 if (__comp(*__first1, *__first2))
5160 ++__first1;
5161 else if (__comp(*__first2, *__first1))
5162 ++__first2;
5163 else
5164 {
5165 *__result = *__first1;
5166 ++__first1;
5167 ++__first2;
5168 ++__result;
5169 }
5170 return __result;
5171 }
5172
5173 /**
5174 * @brief Return the difference of two sorted ranges.
5175 * @param first1 Start of first range.
5176 * @param last1 End of first range.
5177 * @param first2 Start of second range.
5178 * @param last2 End of second range.
5179 * @return End of the output range.
5180 * @ingroup setoperations
5181 *
5182 * This operation iterates over both ranges, copying elements present in
5183 * the first range but not the second in order to the output range.
5184 * Iterators increment for each range. When the current element of the
5185 * first range is less than the second, that element is copied and the
5186 * iterator advances. If the current element of the second range is less,
5187 * the iterator advances, but no element is copied. If an element is
5188 * contained in both ranges, no elements are copied and both ranges
5189 * advance. The output range may not overlap either input range.
5190 */
5191 template<typename _InputIterator1, typename _InputIterator2,
5192 typename _OutputIterator>
5193 _OutputIterator
5194 set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5195 _InputIterator2 __first2, _InputIterator2 __last2,
5196 _OutputIterator __result)
5197 {
5198 typedef typename iterator_traits<_InputIterator1>::value_type
5199 _ValueType1;
5200 typedef typename iterator_traits<_InputIterator2>::value_type
5201 _ValueType2;
5202
5203 // concept requirements
5204 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5205 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5206 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5207 _ValueType1>)
5208 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
5209 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
5210 __glibcxx_requires_sorted(__first1, __last1);
5211 __glibcxx_requires_sorted(__first2, __last2);
5212
5213 while (__first1 != __last1 && __first2 != __last2)
5214 if (*__first1 < *__first2)
5215 {
5216 *__result = *__first1;
5217 ++__first1;
5218 ++__result;
5219 }
5220 else if (*__first2 < *__first1)
5221 ++__first2;
5222 else
5223 {
5224 ++__first1;
5225 ++__first2;
5226 }
5227 return std::copy(__first1, __last1, __result);
5228 }
5229
5230 /**
5231 * @brief Return the difference of two sorted ranges using comparison
5232 * functor.
5233 * @param first1 Start of first range.
5234 * @param last1 End of first range.
5235 * @param first2 Start of second range.
5236 * @param last2 End of second range.
5237 * @param comp The comparison functor.
5238 * @return End of the output range.
5239 * @ingroup setoperations
5240 *
5241 * This operation iterates over both ranges, copying elements present in
5242 * the first range but not the second in order to the output range.
5243 * Iterators increment for each range. When the current element of the
5244 * first range is less than the second according to @a comp, that element
5245 * is copied and the iterator advances. If the current element of the
5246 * second range is less, no element is copied and the iterator advances.
5247 * If an element is contained in both ranges according to @a comp, no
5248 * elements are copied and both ranges advance. The output range may not
5249 * overlap either input range.
5250 */
5251 template<typename _InputIterator1, typename _InputIterator2,
5252 typename _OutputIterator, typename _Compare>
5253 _OutputIterator
5254 set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5255 _InputIterator2 __first2, _InputIterator2 __last2,
5256 _OutputIterator __result, _Compare __comp)
5257 {
5258 typedef typename iterator_traits<_InputIterator1>::value_type
5259 _ValueType1;
5260 typedef typename iterator_traits<_InputIterator2>::value_type
5261 _ValueType2;
5262
5263 // concept requirements
5264 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5265 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5266 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5267 _ValueType1>)
5268 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5269 _ValueType1, _ValueType2>)
5270 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5271 _ValueType2, _ValueType1>)
5272 __glibcxx_requires_sorted_pred(__first1, __last1, __comp);
5273 __glibcxx_requires_sorted_pred(__first2, __last2, __comp);
5274
5275 while (__first1 != __last1 && __first2 != __last2)
5276 if (__comp(*__first1, *__first2))
5277 {
5278 *__result = *__first1;
5279 ++__first1;
5280 ++__result;
5281 }
5282 else if (__comp(*__first2, *__first1))
5283 ++__first2;
5284 else
5285 {
5286 ++__first1;
5287 ++__first2;
5288 }
5289 return std::copy(__first1, __last1, __result);
5290 }
5291
5292 /**
5293 * @brief Return the symmetric difference of two sorted ranges.
5294 * @param first1 Start of first range.
5295 * @param last1 End of first range.
5296 * @param first2 Start of second range.
5297 * @param last2 End of second range.
5298 * @return End of the output range.
5299 * @ingroup setoperations
5300 *
5301 * This operation iterates over both ranges, copying elements present in
5302 * one range but not the other in order to the output range. Iterators
5303 * increment for each range. When the current element of one range is less
5304 * than the other, that element is copied and the iterator advances. If an
5305 * element is contained in both ranges, no elements are copied and both
5306 * ranges advance. The output range may not overlap either input range.
5307 */
5308 template<typename _InputIterator1, typename _InputIterator2,
5309 typename _OutputIterator>
5310 _OutputIterator
5311 set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5312 _InputIterator2 __first2, _InputIterator2 __last2,
5313 _OutputIterator __result)
5314 {
5315 typedef typename iterator_traits<_InputIterator1>::value_type
5316 _ValueType1;
5317 typedef typename iterator_traits<_InputIterator2>::value_type
5318 _ValueType2;
5319
5320 // concept requirements
5321 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5322 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5323 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5324 _ValueType1>)
5325 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5326 _ValueType2>)
5327 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
5328 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
5329 __glibcxx_requires_sorted(__first1, __last1);
5330 __glibcxx_requires_sorted(__first2, __last2);
5331
5332 while (__first1 != __last1 && __first2 != __last2)
5333 if (*__first1 < *__first2)
5334 {
5335 *__result = *__first1;
5336 ++__first1;
5337 ++__result;
5338 }
5339 else if (*__first2 < *__first1)
5340 {
5341 *__result = *__first2;
5342 ++__first2;
5343 ++__result;
5344 }
5345 else
5346 {
5347 ++__first1;
5348 ++__first2;
5349 }
5350 return std::copy(__first2, __last2, std::copy(__first1,
5351 __last1, __result));
5352 }
5353
5354 /**
5355 * @brief Return the symmetric difference of two sorted ranges using
5356 * comparison functor.
5357 * @param first1 Start of first range.
5358 * @param last1 End of first range.
5359 * @param first2 Start of second range.
5360 * @param last2 End of second range.
5361 * @param comp The comparison functor.
5362 * @return End of the output range.
5363 * @ingroup setoperations
5364 *
5365 * This operation iterates over both ranges, copying elements present in
5366 * one range but not the other in order to the output range. Iterators
5367 * increment for each range. When the current element of one range is less
5368 * than the other according to @a comp, that element is copied and the
5369 * iterator advances. If an element is contained in both ranges according
5370 * to @a comp, no elements are copied and both ranges advance. The output
5371 * range may not overlap either input range.
5372 */
5373 template<typename _InputIterator1, typename _InputIterator2,
5374 typename _OutputIterator, typename _Compare>
5375 _OutputIterator
5376 set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
5377 _InputIterator2 __first2, _InputIterator2 __last2,
5378 _OutputIterator __result,
5379 _Compare __comp)
5380 {
5381 typedef typename iterator_traits<_InputIterator1>::value_type
5382 _ValueType1;
5383 typedef typename iterator_traits<_InputIterator2>::value_type
5384 _ValueType2;
5385
5386 // concept requirements
5387 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
5388 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
5389 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5390 _ValueType1>)
5391 __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
5392 _ValueType2>)
5393 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5394 _ValueType1, _ValueType2>)
5395 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5396 _ValueType2, _ValueType1>)
5397 __glibcxx_requires_sorted_pred(__first1, __last1, __comp);
5398 __glibcxx_requires_sorted_pred(__first2, __last2, __comp);
5399
5400 while (__first1 != __last1 && __first2 != __last2)
5401 if (__comp(*__first1, *__first2))
5402 {
5403 *__result = *__first1;
5404 ++__first1;
5405 ++__result;
5406 }
5407 else if (__comp(*__first2, *__first1))
5408 {
5409 *__result = *__first2;
5410 ++__first2;
5411 ++__result;
5412 }
5413 else
5414 {
5415 ++__first1;
5416 ++__first2;
5417 }
5418 return std::copy(__first2, __last2,
5419 std::copy(__first1, __last1, __result));
5420 }
5421
5422
5423 /**
5424 * @brief Return the minimum element in a range.
5425 * @param first Start of range.
5426 * @param last End of range.
5427 * @return Iterator referencing the first instance of the smallest value.
5428 */
5429 template<typename _ForwardIterator>
5430 _ForwardIterator
5431 min_element(_ForwardIterator __first, _ForwardIterator __last)
5432 {
5433 // concept requirements
5434 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5435 __glibcxx_function_requires(_LessThanComparableConcept<
5436 typename iterator_traits<_ForwardIterator>::value_type>)
5437 __glibcxx_requires_valid_range(__first, __last);
5438
5439 if (__first == __last)
5440 return __first;
5441 _ForwardIterator __result = __first;
5442 while (++__first != __last)
5443 if (*__first < *__result)
5444 __result = __first;
5445 return __result;
5446 }
5447
5448 /**
5449 * @brief Return the minimum element in a range using comparison functor.
5450 * @param first Start of range.
5451 * @param last End of range.
5452 * @param comp Comparison functor.
5453 * @return Iterator referencing the first instance of the smallest value
5454 * according to comp.
5455 */
5456 template<typename _ForwardIterator, typename _Compare>
5457 _ForwardIterator
5458 min_element(_ForwardIterator __first, _ForwardIterator __last,
5459 _Compare __comp)
5460 {
5461 // concept requirements
5462 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5463 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5464 typename iterator_traits<_ForwardIterator>::value_type,
5465 typename iterator_traits<_ForwardIterator>::value_type>)
5466 __glibcxx_requires_valid_range(__first, __last);
5467
5468 if (__first == __last)
5469 return __first;
5470 _ForwardIterator __result = __first;
5471 while (++__first != __last)
5472 if (__comp(*__first, *__result))
5473 __result = __first;
5474 return __result;
5475 }
5476
5477 /**
5478 * @brief Return the maximum element in a range.
5479 * @param first Start of range.
5480 * @param last End of range.
5481 * @return Iterator referencing the first instance of the largest value.
5482 */
5483 template<typename _ForwardIterator>
5484 _ForwardIterator
5485 max_element(_ForwardIterator __first, _ForwardIterator __last)
5486 {
5487 // concept requirements
5488 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5489 __glibcxx_function_requires(_LessThanComparableConcept<
5490 typename iterator_traits<_ForwardIterator>::value_type>)
5491 __glibcxx_requires_valid_range(__first, __last);
5492
5493 if (__first == __last)
5494 return __first;
5495 _ForwardIterator __result = __first;
5496 while (++__first != __last)
5497 if (*__result < *__first)
5498 __result = __first;
5499 return __result;
5500 }
5501
5502 /**
5503 * @brief Return the maximum element in a range using comparison functor.
5504 * @param first Start of range.
5505 * @param last End of range.
5506 * @param comp Comparison functor.
5507 * @return Iterator referencing the first instance of the largest value
5508 * according to comp.
5509 */
5510 template<typename _ForwardIterator, typename _Compare>
5511 _ForwardIterator
5512 max_element(_ForwardIterator __first, _ForwardIterator __last,
5513 _Compare __comp)
5514 {
5515 // concept requirements
5516 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
5517 __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
5518 typename iterator_traits<_ForwardIterator>::value_type,
5519 typename iterator_traits<_ForwardIterator>::value_type>)
5520 __glibcxx_requires_valid_range(__first, __last);
5521
5522 if (__first == __last) return __first;
5523 _ForwardIterator __result = __first;
5524 while (++__first != __last)
5525 if (__comp(*__result, *__first))
5526 __result = __first;
5527 return __result;
5528 }
5529
5530 _GLIBCXX_END_NESTED_NAMESPACE
5531
5532 #endif /* _STL_ALGO_H */