1// Multiset implementation -*- C++ -*-
2
3// Copyright (C) 2001-2014 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file bits/stl_multiset.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{set}
54 */
55
56#ifndef _STL_MULTISET_H
57#define _STL_MULTISET_H 1
58
59#include <bits/concept_check.h>
60#if __cplusplus >= 201103L
61#include <initializer_list>
62#endif
63
64namespace std _GLIBCXX_VISIBILITY(default)
65{
66_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
67
68 /**
69 * @brief A standard container made up of elements, which can be retrieved
70 * in logarithmic time.
71 *
72 * @ingroup associative_containers
73 *
74 *
75 * @tparam _Key Type of key objects.
76 * @tparam _Compare Comparison function object type, defaults to less<_Key>.
77 * @tparam _Alloc Allocator type, defaults to allocator<_Key>.
78 *
79 * Meets the requirements of a <a href="tables.html#65">container</a>, a
80 * <a href="tables.html#66">reversible container</a>, and an
81 * <a href="tables.html#69">associative container</a> (using equivalent
82 * keys). For a @c multiset<Key> the key_type and value_type are Key.
83 *
84 * Multisets support bidirectional iterators.
85 *
86 * The private tree data is declared exactly the same way for set and
87 * multiset; the distinction is made entirely in how the tree functions are
88 * called (*_unique versus *_equal, same as the standard).
89 */
90 template <typename _Key, typename _Compare = std::less<_Key>,
91 typename _Alloc = std::allocator<_Key> >
92 class multiset
93 {
94 // concept requirements
95 typedef typename _Alloc::value_type _Alloc_value_type;
96 __glibcxx_class_requires(_Key, _SGIAssignableConcept)
97 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
98 _BinaryFunctionConcept)
99 __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
100
101 public:
102 // typedefs:
103 typedef _Key key_type;
104 typedef _Key value_type;
105 typedef _Compare key_compare;
106 typedef _Compare value_compare;
107 typedef _Alloc allocator_type;
108
109 private:
110 /// This turns a red-black tree into a [multi]set.
111 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
112 rebind<_Key>::other _Key_alloc_type;
113
114 typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
115 key_compare, _Key_alloc_type> _Rep_type;
116 /// The actual tree structure.
117 _Rep_type _M_t;
118
119 typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits;
120
121 public:
122 typedef typename _Alloc_traits::pointer pointer;
123 typedef typename _Alloc_traits::const_pointer const_pointer;
124 typedef typename _Alloc_traits::reference reference;
125 typedef typename _Alloc_traits::const_reference const_reference;
126 // _GLIBCXX_RESOLVE_LIB_DEFECTS
127 // DR 103. set::iterator is required to be modifiable,
128 // but this allows modification of keys.
129 typedef typename _Rep_type::const_iterator iterator;
130 typedef typename _Rep_type::const_iterator const_iterator;
131 typedef typename _Rep_type::const_reverse_iterator reverse_iterator;
132 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
133 typedef typename _Rep_type::size_type size_type;
134 typedef typename _Rep_type::difference_type difference_type;
135
136 // allocation/deallocation
137 /**
138 * @brief Default constructor creates no elements.
139 */
140 multiset()
141 : _M_t() { }
142
143 /**
144 * @brief Creates a %multiset with no elements.
145 * @param __comp Comparator to use.
146 * @param __a An allocator object.
147 */
148 explicit
149 multiset(const _Compare& __comp,
150 const allocator_type& __a = allocator_type())
151 : _M_t(__comp, _Key_alloc_type(__a)) { }
152
153 /**
154 * @brief Builds a %multiset from a range.
155 * @param __first An input iterator.
156 * @param __last An input iterator.
157 *
158 * Create a %multiset consisting of copies of the elements from
159 * [first,last). This is linear in N if the range is already sorted,
160 * and NlogN otherwise (where N is distance(__first,__last)).
161 */
162 template<typename _InputIterator>
163 multiset(_InputIterator __first, _InputIterator __last)
164 : _M_t()
165 { _M_t._M_insert_equal(__first, __last); }
166
167 /**
168 * @brief Builds a %multiset from a range.
169 * @param __first An input iterator.
170 * @param __last An input iterator.
171 * @param __comp A comparison functor.
172 * @param __a An allocator object.
173 *
174 * Create a %multiset consisting of copies of the elements from
175 * [__first,__last). This is linear in N if the range is already sorted,
176 * and NlogN otherwise (where N is distance(__first,__last)).
177 */
178 template<typename _InputIterator>
179 multiset(_InputIterator __first, _InputIterator __last,
180 const _Compare& __comp,
181 const allocator_type& __a = allocator_type())
182 : _M_t(__comp, _Key_alloc_type(__a))
183 { _M_t._M_insert_equal(__first, __last); }
184
185 /**
186 * @brief %Multiset copy constructor.
187 * @param __x A %multiset of identical element and allocator types.
188 *
189 * The newly-created %multiset uses a copy of the allocation object used
190 * by @a __x.
191 */
192 multiset(const multiset& __x)
193 : _M_t(__x._M_t) { }
194
195#if __cplusplus >= 201103L
196 /**
197 * @brief %Multiset move constructor.
198 * @param __x A %multiset of identical element and allocator types.
199 *
200 * The newly-created %multiset contains the exact contents of @a __x.
201 * The contents of @a __x are a valid, but unspecified %multiset.
202 */
203 multiset(multiset&& __x)
204 noexcept(is_nothrow_copy_constructible<_Compare>::value)
205 : _M_t(std::move(__x._M_t)) { }
206
207 /**
208 * @brief Builds a %multiset from an initializer_list.
209 * @param __l An initializer_list.
210 * @param __comp A comparison functor.
211 * @param __a An allocator object.
212 *
213 * Create a %multiset consisting of copies of the elements from
214 * the list. This is linear in N if the list is already sorted,
215 * and NlogN otherwise (where N is @a __l.size()).
216 */
217 multiset(initializer_list<value_type> __l,
218 const _Compare& __comp = _Compare(),
219 const allocator_type& __a = allocator_type())
220 : _M_t(__comp, _Key_alloc_type(__a))
221 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
222
223 /// Allocator-extended default constructor.
224 explicit
225 multiset(const allocator_type& __a)
226 : _M_t(_Compare(), _Key_alloc_type(__a)) { }
227
228 /// Allocator-extended copy constructor.
229 multiset(const multiset& __m, const allocator_type& __a)
230 : _M_t(__m._M_t, _Key_alloc_type(__a)) { }
231
232 /// Allocator-extended move constructor.
233 multiset(multiset&& __m, const allocator_type& __a)
234 noexcept(is_nothrow_copy_constructible<_Compare>::value
235 && _Alloc_traits::_S_always_equal())
236 : _M_t(std::move(__m._M_t), _Key_alloc_type(__a)) { }
237
238 /// Allocator-extended initialier-list constructor.
239 multiset(initializer_list<value_type> __l, const allocator_type& __a)
240 : _M_t(_Compare(), _Key_alloc_type(__a))
241 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
242
243 /// Allocator-extended range constructor.
244 template<typename _InputIterator>
245 multiset(_InputIterator __first, _InputIterator __last,
246 const allocator_type& __a)
247 : _M_t(_Compare(), _Key_alloc_type(__a))
248 { _M_t._M_insert_equal(__first, __last); }
249#endif
250
251 /**
252 * @brief %Multiset assignment operator.
253 * @param __x A %multiset of identical element and allocator types.
254 *
255 * All the elements of @a __x are copied, but unlike the copy
256 * constructor, the allocator object is not copied.
257 */
258 multiset&
259 operator=(const multiset& __x)
260 {
261 _M_t = __x._M_t;
262 return *this;
263 }
264
265#if __cplusplus >= 201103L
266 /**
267 * @brief %Multiset move assignment operator.
268 * @param __x A %multiset of identical element and allocator types.
269 *
270 * The contents of @a __x are moved into this %multiset (without
271 * copying if the allocators compare equal or get moved on assignment).
272 * Afterwards @a __x is in a valid, but unspecified state.
273 */
274 multiset&
275 operator=(multiset&& __x) noexcept(_Alloc_traits::_S_nothrow_move())
276 {
277 if (!_M_t._M_move_assign(__x._M_t))
278 {
279 // The rvalue's allocator cannot be moved and is not equal,
280 // so we need to individually move each element.
281 clear();
282 insert(std::__make_move_if_noexcept_iterator(__x._M_t.begin()),
283 std::__make_move_if_noexcept_iterator(__x._M_t.end()));
284 __x.clear();
285 }
286 return *this;
287 }
288
289 /**
290 * @brief %Multiset list assignment operator.
291 * @param __l An initializer_list.
292 *
293 * This function fills a %multiset with copies of the elements in the
294 * initializer list @a __l.
295 *
296 * Note that the assignment completely changes the %multiset and
297 * that the resulting %multiset's size is the same as the number
298 * of elements assigned. Old data may be lost.
299 */
300 multiset&
301 operator=(initializer_list<value_type> __l)
302 {
303 this->clear();
304 this->insert(__l.begin(), __l.end());
305 return *this;
306 }
307#endif
308
309 // accessors:
310
311 /// Returns the comparison object.
312 key_compare
313 key_comp() const
314 { return _M_t.key_comp(); }
315 /// Returns the comparison object.
316 value_compare
317 value_comp() const
318 { return _M_t.key_comp(); }
319 /// Returns the memory allocation object.
320 allocator_type
321 get_allocator() const _GLIBCXX_NOEXCEPT
322 { return allocator_type(_M_t.get_allocator()); }
323
324 /**
325 * Returns a read-only (constant) iterator that points to the first
326 * element in the %multiset. Iteration is done in ascending order
327 * according to the keys.
328 */
329 iterator
330 begin() const _GLIBCXX_NOEXCEPT
331 { return _M_t.begin(); }
332
333 /**
334 * Returns a read-only (constant) iterator that points one past the last
335 * element in the %multiset. Iteration is done in ascending order
336 * according to the keys.
337 */
338 iterator
339 end() const _GLIBCXX_NOEXCEPT
340 { return _M_t.end(); }
341
342 /**
343 * Returns a read-only (constant) reverse iterator that points to the
344 * last element in the %multiset. Iteration is done in descending order
345 * according to the keys.
346 */
347 reverse_iterator
348 rbegin() const _GLIBCXX_NOEXCEPT
349 { return _M_t.rbegin(); }
350
351 /**
352 * Returns a read-only (constant) reverse iterator that points to the
353 * last element in the %multiset. Iteration is done in descending order
354 * according to the keys.
355 */
356 reverse_iterator
357 rend() const _GLIBCXX_NOEXCEPT
358 { return _M_t.rend(); }
359
360#if __cplusplus >= 201103L
361 /**
362 * Returns a read-only (constant) iterator that points to the first
363 * element in the %multiset. Iteration is done in ascending order
364 * according to the keys.
365 */
366 iterator
367 cbegin() const noexcept
368 { return _M_t.begin(); }
369
370 /**
371 * Returns a read-only (constant) iterator that points one past the last
372 * element in the %multiset. Iteration is done in ascending order
373 * according to the keys.
374 */
375 iterator
376 cend() const noexcept
377 { return _M_t.end(); }
378
379 /**
380 * Returns a read-only (constant) reverse iterator that points to the
381 * last element in the %multiset. Iteration is done in descending order
382 * according to the keys.
383 */
384 reverse_iterator
385 crbegin() const noexcept
386 { return _M_t.rbegin(); }
387
388 /**
389 * Returns a read-only (constant) reverse iterator that points to the
390 * last element in the %multiset. Iteration is done in descending order
391 * according to the keys.
392 */
393 reverse_iterator
394 crend() const noexcept
395 { return _M_t.rend(); }
396#endif
397
398 /// Returns true if the %set is empty.
399 bool
400 empty() const _GLIBCXX_NOEXCEPT
401 { return _M_t.empty(); }
402
403 /// Returns the size of the %set.
404 size_type
405 size() const _GLIBCXX_NOEXCEPT
406 { return _M_t.size(); }
407
408 /// Returns the maximum size of the %set.
409 size_type
410 max_size() const _GLIBCXX_NOEXCEPT
411 { return _M_t.max_size(); }
412
413 /**
414 * @brief Swaps data with another %multiset.
415 * @param __x A %multiset of the same element and allocator types.
416 *
417 * This exchanges the elements between two multisets in constant time.
418 * (It is only swapping a pointer, an integer, and an instance of the @c
419 * Compare type (which itself is often stateless and empty), so it should
420 * be quite fast.)
421 * Note that the global std::swap() function is specialized such that
422 * std::swap(s1,s2) will feed to this function.
423 */
424 void
425 swap(multiset& __x)
426#if __cplusplus >= 201103L
427 noexcept(_Alloc_traits::_S_nothrow_swap())
428#endif
429 { _M_t.swap(__x._M_t); }
430
431 // insert/erase
432#if __cplusplus >= 201103L
433 /**
434 * @brief Builds and inserts an element into the %multiset.
435 * @param __args Arguments used to generate the element instance to be
436 * inserted.
437 * @return An iterator that points to the inserted element.
438 *
439 * This function inserts an element into the %multiset. Contrary
440 * to a std::set the %multiset does not rely on unique keys and thus
441 * multiple copies of the same element can be inserted.
442 *
443 * Insertion requires logarithmic time.
444 */
445 template<typename... _Args>
446 iterator
447 emplace(_Args&&... __args)
448 { return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
449
450 /**
451 * @brief Builds and inserts an element into the %multiset.
452 * @param __pos An iterator that serves as a hint as to where the
453 * element should be inserted.
454 * @param __args Arguments used to generate the element instance to be
455 * inserted.
456 * @return An iterator that points to the inserted element.
457 *
458 * This function inserts an element into the %multiset. Contrary
459 * to a std::set the %multiset does not rely on unique keys and thus
460 * multiple copies of the same element can be inserted.
461 *
462 * Note that the first parameter is only a hint and can potentially
463 * improve the performance of the insertion process. A bad hint would
464 * cause no gains in efficiency.
465 *
466 * See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
467 * for more on @a hinting.
468 *
469 * Insertion requires logarithmic time (if the hint is not taken).
470 */
471 template<typename... _Args>
472 iterator
473 emplace_hint(const_iterator __pos, _Args&&... __args)
474 {
475 return _M_t._M_emplace_hint_equal(__pos,
476 std::forward<_Args>(__args)...);
477 }
478#endif
479
480 /**
481 * @brief Inserts an element into the %multiset.
482 * @param __x Element to be inserted.
483 * @return An iterator that points to the inserted element.
484 *
485 * This function inserts an element into the %multiset. Contrary
486 * to a std::set the %multiset does not rely on unique keys and thus
487 * multiple copies of the same element can be inserted.
488 *
489 * Insertion requires logarithmic time.
490 */
491 iterator
492 insert(const value_type& __x)
493 { return _M_t._M_insert_equal(__x); }
494
495#if __cplusplus >= 201103L
496 iterator
497 insert(value_type&& __x)
498 { return _M_t._M_insert_equal(std::move(__x)); }
499#endif
500
501 /**
502 * @brief Inserts an element into the %multiset.
503 * @param __position An iterator that serves as a hint as to where the
504 * element should be inserted.
505 * @param __x Element to be inserted.
506 * @return An iterator that points to the inserted element.
507 *
508 * This function inserts an element into the %multiset. Contrary
509 * to a std::set the %multiset does not rely on unique keys and thus
510 * multiple copies of the same element can be inserted.
511 *
512 * Note that the first parameter is only a hint and can potentially
513 * improve the performance of the insertion process. A bad hint would
514 * cause no gains in efficiency.
515 *
516 * See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
517 * for more on @a hinting.
518 *
519 * Insertion requires logarithmic time (if the hint is not taken).
520 */
521 iterator
522 insert(const_iterator __position, const value_type& __x)
523 { return _M_t._M_insert_equal_(__position, __x); }
524
525#if __cplusplus >= 201103L
526 iterator
527 insert(const_iterator __position, value_type&& __x)
528 { return _M_t._M_insert_equal_(__position, std::move(__x)); }
529#endif
530
531 /**
532 * @brief A template function that tries to insert a range of elements.
533 * @param __first Iterator pointing to the start of the range to be
534 * inserted.
535 * @param __last Iterator pointing to the end of the range.
536 *
537 * Complexity similar to that of the range constructor.
538 */
539 template<typename _InputIterator>
540 void
541 insert(_InputIterator __first, _InputIterator __last)
542 { _M_t._M_insert_equal(__first, __last); }
543
544#if __cplusplus >= 201103L
545 /**
546 * @brief Attempts to insert a list of elements into the %multiset.
547 * @param __l A std::initializer_list<value_type> of elements
548 * to be inserted.
549 *
550 * Complexity similar to that of the range constructor.
551 */
552 void
553 insert(initializer_list<value_type> __l)
554 { this->insert(__l.begin(), __l.end()); }
555#endif
556
557#if __cplusplus >= 201103L
558 // _GLIBCXX_RESOLVE_LIB_DEFECTS
559 // DR 130. Associative erase should return an iterator.
560 /**
561 * @brief Erases an element from a %multiset.
562 * @param __position An iterator pointing to the element to be erased.
563 * @return An iterator pointing to the element immediately following
564 * @a position prior to the element being erased. If no such
565 * element exists, end() is returned.
566 *
567 * This function erases an element, pointed to by the given iterator,
568 * from a %multiset. Note that this function only erases the element,
569 * and that if the element is itself a pointer, the pointed-to memory is
570 * not touched in any way. Managing the pointer is the user's
571 * responsibility.
572 */
573 _GLIBCXX_ABI_TAG_CXX11
574 iterator
575 erase(const_iterator __position)
576 { return _M_t.erase(__position); }
577#else
578 /**
579 * @brief Erases an element from a %multiset.
580 * @param __position An iterator pointing to the element to be erased.
581 *
582 * This function erases an element, pointed to by the given iterator,
583 * from a %multiset. Note that this function only erases the element,
584 * and that if the element is itself a pointer, the pointed-to memory is
585 * not touched in any way. Managing the pointer is the user's
586 * responsibility.
587 */
588 void
589 erase(iterator __position)
590 { _M_t.erase(__position); }
591#endif
592
593 /**
594 * @brief Erases elements according to the provided key.
595 * @param __x Key of element to be erased.
596 * @return The number of elements erased.
597 *
598 * This function erases all elements located by the given key from a
599 * %multiset.
600 * Note that this function only erases the element, and that if
601 * the element is itself a pointer, the pointed-to memory is not touched
602 * in any way. Managing the pointer is the user's responsibility.
603 */
604 size_type
605 erase(const key_type& __x)
606 { return _M_t.erase(__x); }
607
608#if __cplusplus >= 201103L
609 // _GLIBCXX_RESOLVE_LIB_DEFECTS
610 // DR 130. Associative erase should return an iterator.
611 /**
612 * @brief Erases a [first,last) range of elements from a %multiset.
613 * @param __first Iterator pointing to the start of the range to be
614 * erased.
615 * @param __last Iterator pointing to the end of the range to
616 * be erased.
617 * @return The iterator @a last.
618 *
619 * This function erases a sequence of elements from a %multiset.
620 * Note that this function only erases the elements, and that if
621 * the elements themselves are pointers, the pointed-to memory is not
622 * touched in any way. Managing the pointer is the user's
623 * responsibility.
624 */
625 _GLIBCXX_ABI_TAG_CXX11
626 iterator
627 erase(const_iterator __first, const_iterator __last)
628 { return _M_t.erase(__first, __last); }
629#else
630 /**
631 * @brief Erases a [first,last) range of elements from a %multiset.
632 * @param first Iterator pointing to the start of the range to be
633 * erased.
634 * @param last Iterator pointing to the end of the range to be erased.
635 *
636 * This function erases a sequence of elements from a %multiset.
637 * Note that this function only erases the elements, and that if
638 * the elements themselves are pointers, the pointed-to memory is not
639 * touched in any way. Managing the pointer is the user's
640 * responsibility.
641 */
642 void
643 erase(iterator __first, iterator __last)
644 { _M_t.erase(__first, __last); }
645#endif
646
647 /**
648 * Erases all elements in a %multiset. Note that this function only
649 * erases the elements, and that if the elements themselves are pointers,
650 * the pointed-to memory is not touched in any way. Managing the pointer
651 * is the user's responsibility.
652 */
653 void
654 clear() _GLIBCXX_NOEXCEPT
655 { _M_t.clear(); }
656
657 // multiset operations:
658
659 /**
660 * @brief Finds the number of elements with given key.
661 * @param __x Key of elements to be located.
662 * @return Number of elements with specified key.
663 */
664 size_type
665 count(const key_type& __x) const
666 { return _M_t.count(__x); }
667
668 // _GLIBCXX_RESOLVE_LIB_DEFECTS
669 // 214. set::find() missing const overload
670 //@{
671 /**
672 * @brief Tries to locate an element in a %set.
673 * @param __x Element to be located.
674 * @return Iterator pointing to sought-after element, or end() if not
675 * found.
676 *
677 * This function takes a key and tries to locate the element with which
678 * the key matches. If successful the function returns an iterator
679 * pointing to the sought after element. If unsuccessful it returns the
680 * past-the-end ( @c end() ) iterator.
681 */
682 iterator
683 find(const key_type& __x)
684 { return _M_t.find(__x); }
685
686 const_iterator
687 find(const key_type& __x) const
688 { return _M_t.find(__x); }
689 //@}
690
691 //@{
692 /**
693 * @brief Finds the beginning of a subsequence matching given key.
694 * @param __x Key to be located.
695 * @return Iterator pointing to first element equal to or greater
696 * than key, or end().
697 *
698 * This function returns the first element of a subsequence of elements
699 * that matches the given key. If unsuccessful it returns an iterator
700 * pointing to the first element that has a greater value than given key
701 * or end() if no such element exists.
702 */
703 iterator
704 lower_bound(const key_type& __x)
705 { return _M_t.lower_bound(__x); }
706
707 const_iterator
708 lower_bound(const key_type& __x) const
709 { return _M_t.lower_bound(__x); }
710 //@}
711
712 //@{
713 /**
714 * @brief Finds the end of a subsequence matching given key.
715 * @param __x Key to be located.
716 * @return Iterator pointing to the first element
717 * greater than key, or end().
718 */
719 iterator
720 upper_bound(const key_type& __x)
721 { return _M_t.upper_bound(__x); }
722
723 const_iterator
724 upper_bound(const key_type& __x) const
725 { return _M_t.upper_bound(__x); }
726 //@}
727
728 //@{
729 /**
730 * @brief Finds a subsequence matching given key.
731 * @param __x Key to be located.
732 * @return Pair of iterators that possibly points to the subsequence
733 * matching given key.
734 *
735 * This function is equivalent to
736 * @code
737 * std::make_pair(c.lower_bound(val),
738 * c.upper_bound(val))
739 * @endcode
740 * (but is faster than making the calls separately).
741 *
742 * This function probably only makes sense for multisets.
743 */
744 std::pair<iterator, iterator>
745 equal_range(const key_type& __x)
746 { return _M_t.equal_range(__x); }
747
748 std::pair<const_iterator, const_iterator>
749 equal_range(const key_type& __x) const
750 { return _M_t.equal_range(__x); }
751 //@}
752
753 template<typename _K1, typename _C1, typename _A1>
754 friend bool
755 operator==(const multiset<_K1, _C1, _A1>&,
756 const multiset<_K1, _C1, _A1>&);
757
758 template<typename _K1, typename _C1, typename _A1>
759 friend bool
760 operator< (const multiset<_K1, _C1, _A1>&,
761 const multiset<_K1, _C1, _A1>&);
762 };
763
764 /**
765 * @brief Multiset equality comparison.
766 * @param __x A %multiset.
767 * @param __y A %multiset of the same type as @a __x.
768 * @return True iff the size and elements of the multisets are equal.
769 *
770 * This is an equivalence relation. It is linear in the size of the
771 * multisets.
772 * Multisets are considered equivalent if their sizes are equal, and if
773 * corresponding elements compare equal.
774 */
775 template<typename _Key, typename _Compare, typename _Alloc>
776 inline bool
777 operator==(const multiset<_Key, _Compare, _Alloc>& __x,
778 const multiset<_Key, _Compare, _Alloc>& __y)
779 { return __x._M_t == __y._M_t; }
780
781 /**
782 * @brief Multiset ordering relation.
783 * @param __x A %multiset.
784 * @param __y A %multiset of the same type as @a __x.
785 * @return True iff @a __x is lexicographically less than @a __y.
786 *
787 * This is a total ordering relation. It is linear in the size of the
788 * sets. The elements must be comparable with @c <.
789 *
790 * See std::lexicographical_compare() for how the determination is made.
791 */
792 template<typename _Key, typename _Compare, typename _Alloc>
793 inline bool
794 operator<(const multiset<_Key, _Compare, _Alloc>& __x,
795 const multiset<_Key, _Compare, _Alloc>& __y)
796 { return __x._M_t < __y._M_t; }
797
798 /// Returns !(x == y).
799 template<typename _Key, typename _Compare, typename _Alloc>
800 inline bool
801 operator!=(const multiset<_Key, _Compare, _Alloc>& __x,
802 const multiset<_Key, _Compare, _Alloc>& __y)
803 { return !(__x == __y); }
804
805 /// Returns y < x.
806 template<typename _Key, typename _Compare, typename _Alloc>
807 inline bool
808 operator>(const multiset<_Key,_Compare,_Alloc>& __x,
809 const multiset<_Key,_Compare,_Alloc>& __y)
810 { return __y < __x; }
811
812 /// Returns !(y < x)
813 template<typename _Key, typename _Compare, typename _Alloc>
814 inline bool
815 operator<=(const multiset<_Key, _Compare, _Alloc>& __x,
816 const multiset<_Key, _Compare, _Alloc>& __y)
817 { return !(__y < __x); }
818
819 /// Returns !(x < y)
820 template<typename _Key, typename _Compare, typename _Alloc>
821 inline bool
822 operator>=(const multiset<_Key, _Compare, _Alloc>& __x,
823 const multiset<_Key, _Compare, _Alloc>& __y)
824 { return !(__x < __y); }
825
826 /// See std::multiset::swap().
827 template<typename _Key, typename _Compare, typename _Alloc>
828 inline void
829 swap(multiset<_Key, _Compare, _Alloc>& __x,
830 multiset<_Key, _Compare, _Alloc>& __y)
831 { __x.swap(__y); }
832
833_GLIBCXX_END_NAMESPACE_CONTAINER
834} // namespace std
835
836#endif /* _STL_MULTISET_H */
837