1// Multimap implementation -*- C++ -*-
2
3// Copyright (C) 2001-2018 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) 1996,1997
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_multimap.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{map}
54 */
55
56#ifndef _STL_MULTIMAP_H
57#define _STL_MULTIMAP_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_VERSION
67_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
68
69 template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
70 class map;
71
72 /**
73 * @brief A standard container made up of (key,value) pairs, which can be
74 * retrieved based on a key, in logarithmic time.
75 *
76 * @ingroup associative_containers
77 *
78 * @tparam _Key Type of key objects.
79 * @tparam _Tp Type of mapped objects.
80 * @tparam _Compare Comparison function object type, defaults to less<_Key>.
81 * @tparam _Alloc Allocator type, defaults to
82 * allocator<pair<const _Key, _Tp>.
83 *
84 * Meets the requirements of a <a href="tables.html#65">container</a>, a
85 * <a href="tables.html#66">reversible container</a>, and an
86 * <a href="tables.html#69">associative container</a> (using equivalent
87 * keys). For a @c multimap<Key,T> the key_type is Key, the mapped_type
88 * is T, and the value_type is std::pair<const Key,T>.
89 *
90 * Multimaps support bidirectional iterators.
91 *
92 * The private tree data is declared exactly the same way for map and
93 * multimap; the distinction is made entirely in how the tree functions are
94 * called (*_unique versus *_equal, same as the standard).
95 */
96 template <typename _Key, typename _Tp,
97 typename _Compare = std::less<_Key>,
98 typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
99 class multimap
100 {
101 public:
102 typedef _Key key_type;
103 typedef _Tp mapped_type;
104 typedef std::pair<const _Key, _Tp> value_type;
105 typedef _Compare key_compare;
106 typedef _Alloc allocator_type;
107
108 private:
109#ifdef _GLIBCXX_CONCEPT_CHECKS
110 // concept requirements
111 typedef typename _Alloc::value_type _Alloc_value_type;
112# if __cplusplus < 201103L
113 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
114# endif
115 __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
116 _BinaryFunctionConcept)
117 __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
118#endif
119
120#if __cplusplus >= 201103L && defined(__STRICT_ANSI__)
121 static_assert(is_same<typename _Alloc::value_type, value_type>::value,
122 "std::multimap must have the same value_type as its allocator");
123#endif
124
125 public:
126 class value_compare
127 : public std::binary_function<value_type, value_type, bool>
128 {
129 friend class multimap<_Key, _Tp, _Compare, _Alloc>;
130 protected:
131 _Compare comp;
132
133 value_compare(_Compare __c)
134 : comp(__c) { }
135
136 public:
137 bool operator()(const value_type& __x, const value_type& __y) const
138 { return comp(__x.first, __y.first); }
139 };
140
141 private:
142 /// This turns a red-black tree into a [multi]map.
143 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
144 rebind<value_type>::other _Pair_alloc_type;
145
146 typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
147 key_compare, _Pair_alloc_type> _Rep_type;
148 /// The actual tree structure.
149 _Rep_type _M_t;
150
151 typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits;
152
153 public:
154 // many of these are specified differently in ISO, but the following are
155 // "functionally equivalent"
156 typedef typename _Alloc_traits::pointer pointer;
157 typedef typename _Alloc_traits::const_pointer const_pointer;
158 typedef typename _Alloc_traits::reference reference;
159 typedef typename _Alloc_traits::const_reference const_reference;
160 typedef typename _Rep_type::iterator iterator;
161 typedef typename _Rep_type::const_iterator const_iterator;
162 typedef typename _Rep_type::size_type size_type;
163 typedef typename _Rep_type::difference_type difference_type;
164 typedef typename _Rep_type::reverse_iterator reverse_iterator;
165 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
166
167#if __cplusplus > 201402L
168 using node_type = typename _Rep_type::node_type;
169#endif
170
171 // [23.3.2] construct/copy/destroy
172 // (get_allocator() is also listed in this section)
173
174 /**
175 * @brief Default constructor creates no elements.
176 */
177#if __cplusplus < 201103L
178 multimap() : _M_t() { }
179#else
180 multimap() = default;
181#endif
182
183 /**
184 * @brief Creates a %multimap with no elements.
185 * @param __comp A comparison object.
186 * @param __a An allocator object.
187 */
188 explicit
189 multimap(const _Compare& __comp,
190 const allocator_type& __a = allocator_type())
191 : _M_t(__comp, _Pair_alloc_type(__a)) { }
192
193 /**
194 * @brief %Multimap copy constructor.
195 *
196 * Whether the allocator is copied depends on the allocator traits.
197 */
198#if __cplusplus < 201103L
199 multimap(const multimap& __x)
200 : _M_t(__x._M_t) { }
201#else
202 multimap(const multimap&) = default;
203
204 /**
205 * @brief %Multimap move constructor.
206 *
207 * The newly-created %multimap contains the exact contents of the
208 * moved instance. The moved instance is a valid, but unspecified
209 * %multimap.
210 */
211 multimap(multimap&&) = default;
212
213 /**
214 * @brief Builds a %multimap from an initializer_list.
215 * @param __l An initializer_list.
216 * @param __comp A comparison functor.
217 * @param __a An allocator object.
218 *
219 * Create a %multimap consisting of copies of the elements from
220 * the initializer_list. This is linear in N if the list is already
221 * sorted, and NlogN otherwise (where N is @a __l.size()).
222 */
223 multimap(initializer_list<value_type> __l,
224 const _Compare& __comp = _Compare(),
225 const allocator_type& __a = allocator_type())
226 : _M_t(__comp, _Pair_alloc_type(__a))
227 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
228
229 /// Allocator-extended default constructor.
230 explicit
231 multimap(const allocator_type& __a)
232 : _M_t(_Compare(), _Pair_alloc_type(__a)) { }
233
234 /// Allocator-extended copy constructor.
235 multimap(const multimap& __m, const allocator_type& __a)
236 : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
237
238 /// Allocator-extended move constructor.
239 multimap(multimap&& __m, const allocator_type& __a)
240 noexcept(is_nothrow_copy_constructible<_Compare>::value
241 && _Alloc_traits::_S_always_equal())
242 : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
243
244 /// Allocator-extended initialier-list constructor.
245 multimap(initializer_list<value_type> __l, const allocator_type& __a)
246 : _M_t(_Compare(), _Pair_alloc_type(__a))
247 { _M_t._M_insert_equal(__l.begin(), __l.end()); }
248
249 /// Allocator-extended range constructor.
250 template<typename _InputIterator>
251 multimap(_InputIterator __first, _InputIterator __last,
252 const allocator_type& __a)
253 : _M_t(_Compare(), _Pair_alloc_type(__a))
254 { _M_t._M_insert_equal(__first, __last); }
255#endif
256
257 /**
258 * @brief Builds a %multimap from a range.
259 * @param __first An input iterator.
260 * @param __last An input iterator.
261 *
262 * Create a %multimap consisting of copies of the elements from
263 * [__first,__last). This is linear in N if the range is already sorted,
264 * and NlogN otherwise (where N is distance(__first,__last)).
265 */
266 template<typename _InputIterator>
267 multimap(_InputIterator __first, _InputIterator __last)
268 : _M_t()
269 { _M_t._M_insert_equal(__first, __last); }
270
271 /**
272 * @brief Builds a %multimap from a range.
273 * @param __first An input iterator.
274 * @param __last An input iterator.
275 * @param __comp A comparison functor.
276 * @param __a An allocator object.
277 *
278 * Create a %multimap consisting of copies of the elements from
279 * [__first,__last). This is linear in N if the range is already sorted,
280 * and NlogN otherwise (where N is distance(__first,__last)).
281 */
282 template<typename _InputIterator>
283 multimap(_InputIterator __first, _InputIterator __last,
284 const _Compare& __comp,
285 const allocator_type& __a = allocator_type())
286 : _M_t(__comp, _Pair_alloc_type(__a))
287 { _M_t._M_insert_equal(__first, __last); }
288
289#if __cplusplus >= 201103L
290 /**
291 * The dtor only erases the elements, and note that if the elements
292 * themselves are pointers, the pointed-to memory is not touched in any
293 * way. Managing the pointer is the user's responsibility.
294 */
295 ~multimap() = default;
296#endif
297
298 /**
299 * @brief %Multimap assignment operator.
300 *
301 * Whether the allocator is copied depends on the allocator traits.
302 */
303#if __cplusplus < 201103L
304 multimap&
305 operator=(const multimap& __x)
306 {
307 _M_t = __x._M_t;
308 return *this;
309 }
310#else
311 multimap&
312 operator=(const multimap&) = default;
313
314 /// Move assignment operator.
315 multimap&
316 operator=(multimap&&) = default;
317
318 /**
319 * @brief %Multimap list assignment operator.
320 * @param __l An initializer_list.
321 *
322 * This function fills a %multimap with copies of the elements
323 * in the initializer list @a __l.
324 *
325 * Note that the assignment completely changes the %multimap and
326 * that the resulting %multimap's size is the same as the number
327 * of elements assigned.
328 */
329 multimap&
330 operator=(initializer_list<value_type> __l)
331 {
332 _M_t._M_assign_equal(__l.begin(), __l.end());
333 return *this;
334 }
335#endif
336
337 /// Get a copy of the memory allocation object.
338 allocator_type
339 get_allocator() const _GLIBCXX_NOEXCEPT
340 { return allocator_type(_M_t.get_allocator()); }
341
342 // iterators
343 /**
344 * Returns a read/write iterator that points to the first pair in the
345 * %multimap. Iteration is done in ascending order according to the
346 * keys.
347 */
348 iterator
349 begin() _GLIBCXX_NOEXCEPT
350 { return _M_t.begin(); }
351
352 /**
353 * Returns a read-only (constant) iterator that points to the first pair
354 * in the %multimap. Iteration is done in ascending order according to
355 * the keys.
356 */
357 const_iterator
358 begin() const _GLIBCXX_NOEXCEPT
359 { return _M_t.begin(); }
360
361 /**
362 * Returns a read/write iterator that points one past the last pair in
363 * the %multimap. Iteration is done in ascending order according to the
364 * keys.
365 */
366 iterator
367 end() _GLIBCXX_NOEXCEPT
368 { return _M_t.end(); }
369
370 /**
371 * Returns a read-only (constant) iterator that points one past the last
372 * pair in the %multimap. Iteration is done in ascending order according
373 * to the keys.
374 */
375 const_iterator
376 end() const _GLIBCXX_NOEXCEPT
377 { return _M_t.end(); }
378
379 /**
380 * Returns a read/write reverse iterator that points to the last pair in
381 * the %multimap. Iteration is done in descending order according to the
382 * keys.
383 */
384 reverse_iterator
385 rbegin() _GLIBCXX_NOEXCEPT
386 { return _M_t.rbegin(); }
387
388 /**
389 * Returns a read-only (constant) reverse iterator that points to the
390 * last pair in the %multimap. Iteration is done in descending order
391 * according to the keys.
392 */
393 const_reverse_iterator
394 rbegin() const _GLIBCXX_NOEXCEPT
395 { return _M_t.rbegin(); }
396
397 /**
398 * Returns a read/write reverse iterator that points to one before the
399 * first pair in the %multimap. Iteration is done in descending order
400 * according to the keys.
401 */
402 reverse_iterator
403 rend() _GLIBCXX_NOEXCEPT
404 { return _M_t.rend(); }
405
406 /**
407 * Returns a read-only (constant) reverse iterator that points to one
408 * before the first pair in the %multimap. Iteration is done in
409 * descending order according to the keys.
410 */
411 const_reverse_iterator
412 rend() const _GLIBCXX_NOEXCEPT
413 { return _M_t.rend(); }
414
415#if __cplusplus >= 201103L
416 /**
417 * Returns a read-only (constant) iterator that points to the first pair
418 * in the %multimap. Iteration is done in ascending order according to
419 * the keys.
420 */
421 const_iterator
422 cbegin() const noexcept
423 { return _M_t.begin(); }
424
425 /**
426 * Returns a read-only (constant) iterator that points one past the last
427 * pair in the %multimap. Iteration is done in ascending order according
428 * to the keys.
429 */
430 const_iterator
431 cend() const noexcept
432 { return _M_t.end(); }
433
434 /**
435 * Returns a read-only (constant) reverse iterator that points to the
436 * last pair in the %multimap. Iteration is done in descending order
437 * according to the keys.
438 */
439 const_reverse_iterator
440 crbegin() const noexcept
441 { return _M_t.rbegin(); }
442
443 /**
444 * Returns a read-only (constant) reverse iterator that points to one
445 * before the first pair in the %multimap. Iteration is done in
446 * descending order according to the keys.
447 */
448 const_reverse_iterator
449 crend() const noexcept
450 { return _M_t.rend(); }
451#endif
452
453 // capacity
454 /** Returns true if the %multimap is empty. */
455 bool
456 empty() const _GLIBCXX_NOEXCEPT
457 { return _M_t.empty(); }
458
459 /** Returns the size of the %multimap. */
460 size_type
461 size() const _GLIBCXX_NOEXCEPT
462 { return _M_t.size(); }
463
464 /** Returns the maximum size of the %multimap. */
465 size_type
466 max_size() const _GLIBCXX_NOEXCEPT
467 { return _M_t.max_size(); }
468
469 // modifiers
470#if __cplusplus >= 201103L
471 /**
472 * @brief Build and insert a std::pair into the %multimap.
473 *
474 * @param __args Arguments used to generate a new pair instance (see
475 * std::piecewise_contruct for passing arguments to each
476 * part of the pair constructor).
477 *
478 * @return An iterator that points to the inserted (key,value) pair.
479 *
480 * This function builds and inserts a (key, value) %pair into the
481 * %multimap.
482 * Contrary to a std::map the %multimap does not rely on unique keys and
483 * thus multiple pairs with the same key can be inserted.
484 *
485 * Insertion requires logarithmic time.
486 */
487 template<typename... _Args>
488 iterator
489 emplace(_Args&&... __args)
490 { return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
491
492 /**
493 * @brief Builds and inserts a std::pair into the %multimap.
494 *
495 * @param __pos An iterator that serves as a hint as to where the pair
496 * should be inserted.
497 * @param __args Arguments used to generate a new pair instance (see
498 * std::piecewise_contruct for passing arguments to each
499 * part of the pair constructor).
500 * @return An iterator that points to the inserted (key,value) pair.
501 *
502 * This function inserts a (key, value) pair into the %multimap.
503 * Contrary to a std::map the %multimap does not rely on unique keys and
504 * thus multiple pairs with the same key can be inserted.
505 * Note that the first parameter is only a hint and can potentially
506 * improve the performance of the insertion process. A bad hint would
507 * cause no gains in efficiency.
508 *
509 * For more on @a hinting, see:
510 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
511 *
512 * Insertion requires logarithmic time (if the hint is not taken).
513 */
514 template<typename... _Args>
515 iterator
516 emplace_hint(const_iterator __pos, _Args&&... __args)
517 {
518 return _M_t._M_emplace_hint_equal(__pos,
519 std::forward<_Args>(__args)...);
520 }
521#endif
522
523 /**
524 * @brief Inserts a std::pair into the %multimap.
525 * @param __x Pair to be inserted (see std::make_pair for easy creation
526 * of pairs).
527 * @return An iterator that points to the inserted (key,value) pair.
528 *
529 * This function inserts a (key, value) pair into the %multimap.
530 * Contrary to a std::map the %multimap does not rely on unique keys and
531 * thus multiple pairs with the same key can be inserted.
532 *
533 * Insertion requires logarithmic time.
534 * @{
535 */
536 iterator
537 insert(const value_type& __x)
538 { return _M_t._M_insert_equal(__x); }
539
540#if __cplusplus >= 201103L
541 // _GLIBCXX_RESOLVE_LIB_DEFECTS
542 // 2354. Unnecessary copying when inserting into maps with braced-init
543 iterator
544 insert(value_type&& __x)
545 { return _M_t._M_insert_equal(std::move(__x)); }
546
547 template<typename _Pair, typename = typename
548 std::enable_if<std::is_constructible<value_type,
549 _Pair&&>::value>::type>
550 iterator
551 insert(_Pair&& __x)
552 { return _M_t._M_insert_equal(std::forward<_Pair>(__x)); }
553#endif
554 // @}
555
556 /**
557 * @brief Inserts a std::pair into the %multimap.
558 * @param __position An iterator that serves as a hint as to where the
559 * pair should be inserted.
560 * @param __x Pair to be inserted (see std::make_pair for easy creation
561 * of pairs).
562 * @return An iterator that points to the inserted (key,value) pair.
563 *
564 * This function inserts a (key, value) pair into the %multimap.
565 * Contrary to a std::map the %multimap does not rely on unique keys and
566 * thus multiple pairs with the same key can be inserted.
567 * Note that the first parameter is only a hint and can potentially
568 * improve the performance of the insertion process. A bad hint would
569 * cause no gains in efficiency.
570 *
571 * For more on @a hinting, see:
572 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
573 *
574 * Insertion requires logarithmic time (if the hint is not taken).
575 * @{
576 */
577 iterator
578#if __cplusplus >= 201103L
579 insert(const_iterator __position, const value_type& __x)
580#else
581 insert(iterator __position, const value_type& __x)
582#endif
583 { return _M_t._M_insert_equal_(__position, __x); }
584
585#if __cplusplus >= 201103L
586 // _GLIBCXX_RESOLVE_LIB_DEFECTS
587 // 2354. Unnecessary copying when inserting into maps with braced-init
588 iterator
589 insert(const_iterator __position, value_type&& __x)
590 { return _M_t._M_insert_equal_(__position, std::move(__x)); }
591
592 template<typename _Pair, typename = typename
593 std::enable_if<std::is_constructible<value_type,
594 _Pair&&>::value>::type>
595 iterator
596 insert(const_iterator __position, _Pair&& __x)
597 { return _M_t._M_insert_equal_(__position,
598 std::forward<_Pair>(__x)); }
599#endif
600 // @}
601
602 /**
603 * @brief A template function that attempts to insert a range
604 * of elements.
605 * @param __first Iterator pointing to the start of the range to be
606 * inserted.
607 * @param __last Iterator pointing to the end of the range.
608 *
609 * Complexity similar to that of the range constructor.
610 */
611 template<typename _InputIterator>
612 void
613 insert(_InputIterator __first, _InputIterator __last)
614 { _M_t._M_insert_equal(__first, __last); }
615
616#if __cplusplus >= 201103L
617 /**
618 * @brief Attempts to insert a list of std::pairs into the %multimap.
619 * @param __l A std::initializer_list<value_type> of pairs to be
620 * inserted.
621 *
622 * Complexity similar to that of the range constructor.
623 */
624 void
625 insert(initializer_list<value_type> __l)
626 { this->insert(__l.begin(), __l.end()); }
627#endif
628
629#if __cplusplus > 201402L
630 /// Extract a node.
631 node_type
632 extract(const_iterator __pos)
633 {
634 __glibcxx_assert(__pos != end());
635 return _M_t.extract(__pos);
636 }
637
638 /// Extract a node.
639 node_type
640 extract(const key_type& __x)
641 { return _M_t.extract(__x); }
642
643 /// Re-insert an extracted node.
644 iterator
645 insert(node_type&& __nh)
646 { return _M_t._M_reinsert_node_equal(std::move(__nh)); }
647
648 /// Re-insert an extracted node.
649 iterator
650 insert(const_iterator __hint, node_type&& __nh)
651 { return _M_t._M_reinsert_node_hint_equal(__hint, std::move(__nh)); }
652
653 template<typename, typename>
654 friend class std::_Rb_tree_merge_helper;
655
656 template<typename _C2>
657 void
658 merge(multimap<_Key, _Tp, _C2, _Alloc>& __source)
659 {
660 using _Merge_helper = _Rb_tree_merge_helper<multimap, _C2>;
661 _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
662 }
663
664 template<typename _C2>
665 void
666 merge(multimap<_Key, _Tp, _C2, _Alloc>&& __source)
667 { merge(__source); }
668
669 template<typename _C2>
670 void
671 merge(map<_Key, _Tp, _C2, _Alloc>& __source)
672 {
673 using _Merge_helper = _Rb_tree_merge_helper<multimap, _C2>;
674 _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
675 }
676
677 template<typename _C2>
678 void
679 merge(map<_Key, _Tp, _C2, _Alloc>&& __source)
680 { merge(__source); }
681#endif // C++17
682
683#if __cplusplus >= 201103L
684 // _GLIBCXX_RESOLVE_LIB_DEFECTS
685 // DR 130. Associative erase should return an iterator.
686 /**
687 * @brief Erases an element from a %multimap.
688 * @param __position An iterator pointing to the element to be erased.
689 * @return An iterator pointing to the element immediately following
690 * @a position prior to the element being erased. If no such
691 * element exists, end() is returned.
692 *
693 * This function erases an element, pointed to by the given iterator,
694 * from a %multimap. Note that this function only erases the element,
695 * and that if the element is itself a pointer, the pointed-to memory is
696 * not touched in any way. Managing the pointer is the user's
697 * responsibility.
698 *
699 * @{
700 */
701 iterator
702 erase(const_iterator __position)
703 { return _M_t.erase(__position); }
704
705 // LWG 2059.
706 _GLIBCXX_ABI_TAG_CXX11
707 iterator
708 erase(iterator __position)
709 { return _M_t.erase(__position); }
710 // @}
711#else
712 /**
713 * @brief Erases an element from a %multimap.
714 * @param __position An iterator pointing to the element to be erased.
715 *
716 * This function erases an element, pointed to by the given iterator,
717 * from a %multimap. Note that this function only erases the element,
718 * and that if the element is itself a pointer, the pointed-to memory is
719 * not touched in any way. Managing the pointer is the user's
720 * responsibility.
721 */
722 void
723 erase(iterator __position)
724 { _M_t.erase(__position); }
725#endif
726
727 /**
728 * @brief Erases elements according to the provided key.
729 * @param __x Key of element to be erased.
730 * @return The number of elements erased.
731 *
732 * This function erases all elements located by the given key from a
733 * %multimap.
734 * Note that this function only erases the element, and that if
735 * the element is itself a pointer, the pointed-to memory is not touched
736 * in any way. Managing the pointer is the user's responsibility.
737 */
738 size_type
739 erase(const key_type& __x)
740 { return _M_t.erase(__x); }
741
742#if __cplusplus >= 201103L
743 // _GLIBCXX_RESOLVE_LIB_DEFECTS
744 // DR 130. Associative erase should return an iterator.
745 /**
746 * @brief Erases a [first,last) range of elements from a %multimap.
747 * @param __first Iterator pointing to the start of the range to be
748 * erased.
749 * @param __last Iterator pointing to the end of the range to be
750 * erased .
751 * @return The iterator @a __last.
752 *
753 * This function erases a sequence of elements from a %multimap.
754 * Note that this function only erases the elements, and that if
755 * the elements themselves are pointers, the pointed-to memory is not
756 * touched in any way. Managing the pointer is the user's
757 * responsibility.
758 */
759 iterator
760 erase(const_iterator __first, const_iterator __last)
761 { return _M_t.erase(__first, __last); }
762#else
763 // _GLIBCXX_RESOLVE_LIB_DEFECTS
764 // DR 130. Associative erase should return an iterator.
765 /**
766 * @brief Erases a [first,last) range of elements from a %multimap.
767 * @param __first Iterator pointing to the start of the range to be
768 * erased.
769 * @param __last Iterator pointing to the end of the range to
770 * be erased.
771 *
772 * This function erases a sequence of elements from a %multimap.
773 * Note that this function only erases the elements, and that if
774 * the elements themselves are pointers, the pointed-to memory is not
775 * touched in any way. Managing the pointer is the user's
776 * responsibility.
777 */
778 void
779 erase(iterator __first, iterator __last)
780 { _M_t.erase(__first, __last); }
781#endif
782
783 /**
784 * @brief Swaps data with another %multimap.
785 * @param __x A %multimap of the same element and allocator types.
786 *
787 * This exchanges the elements between two multimaps in constant time.
788 * (It is only swapping a pointer, an integer, and an instance of
789 * the @c Compare type (which itself is often stateless and empty), so it
790 * should be quite fast.)
791 * Note that the global std::swap() function is specialized such that
792 * std::swap(m1,m2) will feed to this function.
793 *
794 * Whether the allocators are swapped depends on the allocator traits.
795 */
796 void
797 swap(multimap& __x)
798 _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
799 { _M_t.swap(__x._M_t); }
800
801 /**
802 * Erases all elements in a %multimap. Note that this function only
803 * erases the elements, and that if the elements themselves are pointers,
804 * the pointed-to memory is not touched in any way. Managing the pointer
805 * is the user's responsibility.
806 */
807 void
808 clear() _GLIBCXX_NOEXCEPT
809 { _M_t.clear(); }
810
811 // observers
812 /**
813 * Returns the key comparison object out of which the %multimap
814 * was constructed.
815 */
816 key_compare
817 key_comp() const
818 { return _M_t.key_comp(); }
819
820 /**
821 * Returns a value comparison object, built from the key comparison
822 * object out of which the %multimap was constructed.
823 */
824 value_compare
825 value_comp() const
826 { return value_compare(_M_t.key_comp()); }
827
828 // multimap operations
829
830 //@{
831 /**
832 * @brief Tries to locate an element in a %multimap.
833 * @param __x Key of (key, value) pair to be located.
834 * @return Iterator pointing to sought-after element,
835 * or end() if not found.
836 *
837 * This function takes a key and tries to locate the element with which
838 * the key matches. If successful the function returns an iterator
839 * pointing to the sought after %pair. If unsuccessful it returns the
840 * past-the-end ( @c end() ) iterator.
841 */
842 iterator
843 find(const key_type& __x)
844 { return _M_t.find(__x); }
845
846#if __cplusplus > 201103L
847 template<typename _Kt>
848 auto
849 find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
850 { return _M_t._M_find_tr(__x); }
851#endif
852 //@}
853
854 //@{
855 /**
856 * @brief Tries to locate an element in a %multimap.
857 * @param __x Key of (key, value) pair to be located.
858 * @return Read-only (constant) iterator pointing to sought-after
859 * element, or end() if not found.
860 *
861 * This function takes a key and tries to locate the element with which
862 * the key matches. If successful the function returns a constant
863 * iterator pointing to the sought after %pair. If unsuccessful it
864 * returns the past-the-end ( @c end() ) iterator.
865 */
866 const_iterator
867 find(const key_type& __x) const
868 { return _M_t.find(__x); }
869
870#if __cplusplus > 201103L
871 template<typename _Kt>
872 auto
873 find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
874 { return _M_t._M_find_tr(__x); }
875#endif
876 //@}
877
878 //@{
879 /**
880 * @brief Finds the number of elements with given key.
881 * @param __x Key of (key, value) pairs to be located.
882 * @return Number of elements with specified key.
883 */
884 size_type
885 count(const key_type& __x) const
886 { return _M_t.count(__x); }
887
888#if __cplusplus > 201103L
889 template<typename _Kt>
890 auto
891 count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
892 { return _M_t._M_count_tr(__x); }
893#endif
894 //@}
895
896 //@{
897 /**
898 * @brief Finds the beginning of a subsequence matching given key.
899 * @param __x Key of (key, value) pair to be located.
900 * @return Iterator pointing to first element equal to or greater
901 * than key, or end().
902 *
903 * This function returns the first element of a subsequence of elements
904 * that matches the given key. If unsuccessful it returns an iterator
905 * pointing to the first element that has a greater value than given key
906 * or end() if no such element exists.
907 */
908 iterator
909 lower_bound(const key_type& __x)
910 { return _M_t.lower_bound(__x); }
911
912#if __cplusplus > 201103L
913 template<typename _Kt>
914 auto
915 lower_bound(const _Kt& __x)
916 -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
917 { return iterator(_M_t._M_lower_bound_tr(__x)); }
918#endif
919 //@}
920
921 //@{
922 /**
923 * @brief Finds the beginning of a subsequence matching given key.
924 * @param __x Key of (key, value) pair to be located.
925 * @return Read-only (constant) iterator pointing to first element
926 * equal to or greater than key, or end().
927 *
928 * This function returns the first element of a subsequence of
929 * elements that matches the given key. If unsuccessful the
930 * iterator will point to the next greatest element or, if no
931 * such greater element exists, to end().
932 */
933 const_iterator
934 lower_bound(const key_type& __x) const
935 { return _M_t.lower_bound(__x); }
936
937#if __cplusplus > 201103L
938 template<typename _Kt>
939 auto
940 lower_bound(const _Kt& __x) const
941 -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
942 { return const_iterator(_M_t._M_lower_bound_tr(__x)); }
943#endif
944 //@}
945
946 //@{
947 /**
948 * @brief Finds the end of a subsequence matching given key.
949 * @param __x Key of (key, value) pair to be located.
950 * @return Iterator pointing to the first element
951 * greater than key, or end().
952 */
953 iterator
954 upper_bound(const key_type& __x)
955 { return _M_t.upper_bound(__x); }
956
957#if __cplusplus > 201103L
958 template<typename _Kt>
959 auto
960 upper_bound(const _Kt& __x)
961 -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
962 { return iterator(_M_t._M_upper_bound_tr(__x)); }
963#endif
964 //@}
965
966 //@{
967 /**
968 * @brief Finds the end of a subsequence matching given key.
969 * @param __x Key of (key, value) pair to be located.
970 * @return Read-only (constant) iterator pointing to first iterator
971 * greater than key, or end().
972 */
973 const_iterator
974 upper_bound(const key_type& __x) const
975 { return _M_t.upper_bound(__x); }
976
977#if __cplusplus > 201103L
978 template<typename _Kt>
979 auto
980 upper_bound(const _Kt& __x) const
981 -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
982 { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
983#endif
984 //@}
985
986 //@{
987 /**
988 * @brief Finds a subsequence matching given key.
989 * @param __x Key of (key, value) pairs to be located.
990 * @return Pair of iterators that possibly points to the subsequence
991 * matching given key.
992 *
993 * This function is equivalent to
994 * @code
995 * std::make_pair(c.lower_bound(val),
996 * c.upper_bound(val))
997 * @endcode
998 * (but is faster than making the calls separately).
999 */
1000 std::pair<iterator, iterator>
1001 equal_range(const key_type& __x)
1002 { return _M_t.equal_range(__x); }
1003
1004#if __cplusplus > 201103L
1005 template<typename _Kt>
1006 auto
1007 equal_range(const _Kt& __x)
1008 -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
1009 { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
1010#endif
1011 //@}
1012
1013 //@{
1014 /**
1015 * @brief Finds a subsequence matching given key.
1016 * @param __x Key of (key, value) pairs to be located.
1017 * @return Pair of read-only (constant) iterators that possibly points
1018 * to the subsequence matching given key.
1019 *
1020 * This function is equivalent to
1021 * @code
1022 * std::make_pair(c.lower_bound(val),
1023 * c.upper_bound(val))
1024 * @endcode
1025 * (but is faster than making the calls separately).
1026 */
1027 std::pair<const_iterator, const_iterator>
1028 equal_range(const key_type& __x) const
1029 { return _M_t.equal_range(__x); }
1030
1031#if __cplusplus > 201103L
1032 template<typename _Kt>
1033 auto
1034 equal_range(const _Kt& __x) const
1035 -> decltype(pair<const_iterator, const_iterator>(
1036 _M_t._M_equal_range_tr(__x)))
1037 {
1038 return pair<const_iterator, const_iterator>(
1039 _M_t._M_equal_range_tr(__x));
1040 }
1041#endif
1042 //@}
1043
1044 template<typename _K1, typename _T1, typename _C1, typename _A1>
1045 friend bool
1046 operator==(const multimap<_K1, _T1, _C1, _A1>&,
1047 const multimap<_K1, _T1, _C1, _A1>&);
1048
1049 template<typename _K1, typename _T1, typename _C1, typename _A1>
1050 friend bool
1051 operator<(const multimap<_K1, _T1, _C1, _A1>&,
1052 const multimap<_K1, _T1, _C1, _A1>&);
1053 };
1054
1055#if __cpp_deduction_guides >= 201606
1056
1057 template<typename _InputIterator,
1058 typename _Compare = less<__iter_key_t<_InputIterator>>,
1059 typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>,
1060 typename = _RequireInputIter<_InputIterator>,
1061 typename = _RequireAllocator<_Allocator>>
1062 multimap(_InputIterator, _InputIterator,
1063 _Compare = _Compare(), _Allocator = _Allocator())
1064 -> multimap<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1065 _Compare, _Allocator>;
1066
1067 template<typename _Key, typename _Tp, typename _Compare = less<_Key>,
1068 typename _Allocator = allocator<pair<const _Key, _Tp>>,
1069 typename = _RequireAllocator<_Allocator>>
1070 multimap(initializer_list<pair<_Key, _Tp>>,
1071 _Compare = _Compare(), _Allocator = _Allocator())
1072 -> multimap<_Key, _Tp, _Compare, _Allocator>;
1073
1074 template<typename _InputIterator, typename _Allocator,
1075 typename = _RequireInputIter<_InputIterator>,
1076 typename = _RequireAllocator<_Allocator>>
1077 multimap(_InputIterator, _InputIterator, _Allocator)
1078 -> multimap<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
1079 less<__iter_key_t<_InputIterator>>, _Allocator>;
1080
1081 template<typename _Key, typename _Tp, typename _Allocator,
1082 typename = _RequireAllocator<_Allocator>>
1083 multimap(initializer_list<pair<_Key, _Tp>>, _Allocator)
1084 -> multimap<_Key, _Tp, less<_Key>, _Allocator>;
1085
1086#endif
1087
1088 /**
1089 * @brief Multimap equality comparison.
1090 * @param __x A %multimap.
1091 * @param __y A %multimap of the same type as @a __x.
1092 * @return True iff the size and elements of the maps are equal.
1093 *
1094 * This is an equivalence relation. It is linear in the size of the
1095 * multimaps. Multimaps are considered equivalent if their sizes are equal,
1096 * and if corresponding elements compare equal.
1097 */
1098 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1099 inline bool
1100 operator==(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1101 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1102 { return __x._M_t == __y._M_t; }
1103
1104 /**
1105 * @brief Multimap ordering relation.
1106 * @param __x A %multimap.
1107 * @param __y A %multimap of the same type as @a __x.
1108 * @return True iff @a x is lexicographically less than @a y.
1109 *
1110 * This is a total ordering relation. It is linear in the size of the
1111 * multimaps. The elements must be comparable with @c <.
1112 *
1113 * See std::lexicographical_compare() for how the determination is made.
1114 */
1115 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1116 inline bool
1117 operator<(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1118 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1119 { return __x._M_t < __y._M_t; }
1120
1121 /// Based on operator==
1122 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1123 inline bool
1124 operator!=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1125 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1126 { return !(__x == __y); }
1127
1128 /// Based on operator<
1129 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1130 inline bool
1131 operator>(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1132 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1133 { return __y < __x; }
1134
1135 /// Based on operator<
1136 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1137 inline bool
1138 operator<=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1139 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1140 { return !(__y < __x); }
1141
1142 /// Based on operator<
1143 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1144 inline bool
1145 operator>=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1146 const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1147 { return !(__x < __y); }
1148
1149 /// See std::multimap::swap().
1150 template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1151 inline void
1152 swap(multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1153 multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1154 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1155 { __x.swap(__y); }
1156
1157_GLIBCXX_END_NAMESPACE_CONTAINER
1158
1159#if __cplusplus > 201402L
1160 // Allow std::multimap access to internals of compatible maps.
1161 template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
1162 typename _Cmp2>
1163 struct
1164 _Rb_tree_merge_helper<_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp1, _Alloc>,
1165 _Cmp2>
1166 {
1167 private:
1168 friend class _GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp1, _Alloc>;
1169
1170 static auto&
1171 _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
1172 { return __map._M_t; }
1173
1174 static auto&
1175 _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
1176 { return __map._M_t; }
1177 };
1178#endif // C++17
1179
1180_GLIBCXX_END_NAMESPACE_VERSION
1181} // namespace std
1182
1183#endif /* _STL_MULTIMAP_H */
1184