xref: /netbsd-src/external/gpl3/gcc/dist/libstdc++-v3/include/bits/stl_multimap.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 // Multimap implementation -*- C++ -*-
2 
3 // Copyright (C) 2001-2016 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 
64 namespace std _GLIBCXX_VISIBILITY(default)
65 {
66 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
67 
68   /**
69    *  @brief A standard container made up of (key,value) pairs, which can be
70    *  retrieved based on a key, in logarithmic time.
71    *
72    *  @ingroup associative_containers
73    *
74    *  @tparam _Key  Type of key objects.
75    *  @tparam  _Tp  Type of mapped objects.
76    *  @tparam _Compare  Comparison function object type, defaults to less<_Key>.
77    *  @tparam _Alloc  Allocator type, defaults to
78    *                  allocator<pair<const _Key, _Tp>.
79    *
80    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
81    *  <a href="tables.html#66">reversible container</a>, and an
82    *  <a href="tables.html#69">associative container</a> (using equivalent
83    *  keys).  For a @c multimap<Key,T> the key_type is Key, the mapped_type
84    *  is T, and the value_type is std::pair<const Key,T>.
85    *
86    *  Multimaps support bidirectional iterators.
87    *
88    *  The private tree data is declared exactly the same way for map and
89    *  multimap; the distinction is made entirely in how the tree functions are
90    *  called (*_unique versus *_equal, same as the standard).
91   */
92   template <typename _Key, typename _Tp,
93 	    typename _Compare = std::less<_Key>,
94 	    typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
95     class multimap
96     {
97     public:
98       typedef _Key                                          key_type;
99       typedef _Tp                                           mapped_type;
100       typedef std::pair<const _Key, _Tp>                    value_type;
101       typedef _Compare                                      key_compare;
102       typedef _Alloc                                        allocator_type;
103 
104     private:
105       // concept requirements
106       typedef typename _Alloc::value_type                   _Alloc_value_type;
107       __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
108       __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
109 				_BinaryFunctionConcept)
110       __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
111 
112     public:
113       class value_compare
114       : public std::binary_function<value_type, value_type, bool>
115       {
116 	friend class multimap<_Key, _Tp, _Compare, _Alloc>;
117       protected:
118 	_Compare comp;
119 
120 	value_compare(_Compare __c)
121 	: comp(__c) { }
122 
123       public:
124 	bool operator()(const value_type& __x, const value_type& __y) const
125 	{ return comp(__x.first, __y.first); }
126       };
127 
128     private:
129       /// This turns a red-black tree into a [multi]map.
130       typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
131 	rebind<value_type>::other _Pair_alloc_type;
132 
133       typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
134 		       key_compare, _Pair_alloc_type> _Rep_type;
135       /// The actual tree structure.
136       _Rep_type _M_t;
137 
138       typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits;
139 
140     public:
141       // many of these are specified differently in ISO, but the following are
142       // "functionally equivalent"
143       typedef typename _Alloc_traits::pointer            pointer;
144       typedef typename _Alloc_traits::const_pointer      const_pointer;
145       typedef typename _Alloc_traits::reference          reference;
146       typedef typename _Alloc_traits::const_reference    const_reference;
147       typedef typename _Rep_type::iterator               iterator;
148       typedef typename _Rep_type::const_iterator         const_iterator;
149       typedef typename _Rep_type::size_type              size_type;
150       typedef typename _Rep_type::difference_type        difference_type;
151       typedef typename _Rep_type::reverse_iterator       reverse_iterator;
152       typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
153 
154       // [23.3.2] construct/copy/destroy
155       // (get_allocator() is also listed in this section)
156 
157       /**
158        *  @brief  Default constructor creates no elements.
159        */
160       multimap()
161       _GLIBCXX_NOEXCEPT_IF(
162 	  is_nothrow_default_constructible<allocator_type>::value
163 	  && is_nothrow_default_constructible<key_compare>::value)
164       : _M_t() { }
165 
166       /**
167        *  @brief  Creates a %multimap with no elements.
168        *  @param  __comp  A comparison object.
169        *  @param  __a  An allocator object.
170        */
171       explicit
172       multimap(const _Compare& __comp,
173 	       const allocator_type& __a = allocator_type())
174       : _M_t(__comp, _Pair_alloc_type(__a)) { }
175 
176       /**
177        *  @brief  %Multimap copy constructor.
178        *  @param  __x  A %multimap of identical element and allocator types.
179        *
180        *  The newly-created %multimap uses a copy of the allocation object
181        *  used by @a __x.
182        */
183       multimap(const multimap& __x)
184       : _M_t(__x._M_t) { }
185 
186 #if __cplusplus >= 201103L
187       /**
188        *  @brief  %Multimap move constructor.
189        *  @param   __x  A %multimap of identical element and allocator types.
190        *
191        *  The newly-created %multimap contains the exact contents of @a __x.
192        *  The contents of @a __x are a valid, but unspecified %multimap.
193        */
194       multimap(multimap&& __x)
195       noexcept(is_nothrow_copy_constructible<_Compare>::value)
196       : _M_t(std::move(__x._M_t)) { }
197 
198       /**
199        *  @brief  Builds a %multimap from an initializer_list.
200        *  @param  __l  An initializer_list.
201        *  @param  __comp  A comparison functor.
202        *  @param  __a  An allocator object.
203        *
204        *  Create a %multimap consisting of copies of the elements from
205        *  the initializer_list.  This is linear in N if the list is already
206        *  sorted, and NlogN otherwise (where N is @a __l.size()).
207        */
208       multimap(initializer_list<value_type> __l,
209 	       const _Compare& __comp = _Compare(),
210 	       const allocator_type& __a = allocator_type())
211       : _M_t(__comp, _Pair_alloc_type(__a))
212       { _M_t._M_insert_equal(__l.begin(), __l.end()); }
213 
214       /// Allocator-extended default constructor.
215       explicit
216       multimap(const allocator_type& __a)
217       : _M_t(_Compare(), _Pair_alloc_type(__a)) { }
218 
219       /// Allocator-extended copy constructor.
220       multimap(const multimap& __m, const allocator_type& __a)
221       : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
222 
223       /// Allocator-extended move constructor.
224       multimap(multimap&& __m, const allocator_type& __a)
225       noexcept(is_nothrow_copy_constructible<_Compare>::value
226 	       && _Alloc_traits::_S_always_equal())
227       : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
228 
229       /// Allocator-extended initialier-list constructor.
230       multimap(initializer_list<value_type> __l, const allocator_type& __a)
231       : _M_t(_Compare(), _Pair_alloc_type(__a))
232       { _M_t._M_insert_equal(__l.begin(), __l.end()); }
233 
234       /// Allocator-extended range constructor.
235       template<typename _InputIterator>
236         multimap(_InputIterator __first, _InputIterator __last,
237 		 const allocator_type& __a)
238 	: _M_t(_Compare(), _Pair_alloc_type(__a))
239         { _M_t._M_insert_equal(__first, __last); }
240 #endif
241 
242       /**
243        *  @brief  Builds a %multimap from a range.
244        *  @param  __first  An input iterator.
245        *  @param  __last  An input iterator.
246        *
247        *  Create a %multimap consisting of copies of the elements from
248        *  [__first,__last).  This is linear in N if the range is already sorted,
249        *  and NlogN otherwise (where N is distance(__first,__last)).
250        */
251       template<typename _InputIterator>
252         multimap(_InputIterator __first, _InputIterator __last)
253 	: _M_t()
254         { _M_t._M_insert_equal(__first, __last); }
255 
256       /**
257        *  @brief  Builds a %multimap from a range.
258        *  @param  __first  An input iterator.
259        *  @param  __last  An input iterator.
260        *  @param  __comp  A comparison functor.
261        *  @param  __a  An allocator object.
262        *
263        *  Create a %multimap consisting of copies of the elements from
264        *  [__first,__last).  This is linear in N if the range is already sorted,
265        *  and NlogN otherwise (where N is distance(__first,__last)).
266        */
267       template<typename _InputIterator>
268         multimap(_InputIterator __first, _InputIterator __last,
269 		 const _Compare& __comp,
270 		 const allocator_type& __a = allocator_type())
271 	: _M_t(__comp, _Pair_alloc_type(__a))
272         { _M_t._M_insert_equal(__first, __last); }
273 
274       // FIXME There is no dtor declared, but we should have something generated
275       // by Doxygen.  I don't know what tags to add to this paragraph to make
276       // that happen:
277       /**
278        *  The dtor only erases the elements, and note that if the elements
279        *  themselves are pointers, the pointed-to memory is not touched in any
280        *  way.  Managing the pointer is the user's responsibility.
281        */
282 
283       /**
284        *  @brief  %Multimap assignment operator.
285        *  @param  __x  A %multimap of identical element and allocator types.
286        *
287        *  All the elements of @a __x are copied, but unlike the copy
288        *  constructor, the allocator object is not copied.
289        */
290       multimap&
291       operator=(const multimap& __x)
292       {
293 	_M_t = __x._M_t;
294 	return *this;
295       }
296 
297 #if __cplusplus >= 201103L
298       /// Move assignment operator.
299       multimap&
300       operator=(multimap&&) = default;
301 
302       /**
303        *  @brief  %Multimap list assignment operator.
304        *  @param  __l  An initializer_list.
305        *
306        *  This function fills a %multimap with copies of the elements
307        *  in the initializer list @a __l.
308        *
309        *  Note that the assignment completely changes the %multimap and
310        *  that the resulting %multimap's size is the same as the number
311        *  of elements assigned.  Old data may be lost.
312        */
313       multimap&
314       operator=(initializer_list<value_type> __l)
315       {
316 	_M_t._M_assign_equal(__l.begin(), __l.end());
317 	return *this;
318       }
319 #endif
320 
321       /// Get a copy of the memory allocation object.
322       allocator_type
323       get_allocator() const _GLIBCXX_NOEXCEPT
324       { return allocator_type(_M_t.get_allocator()); }
325 
326       // iterators
327       /**
328        *  Returns a read/write iterator that points to the first pair in the
329        *  %multimap.  Iteration is done in ascending order according to the
330        *  keys.
331        */
332       iterator
333       begin() _GLIBCXX_NOEXCEPT
334       { return _M_t.begin(); }
335 
336       /**
337        *  Returns a read-only (constant) iterator that points to the first pair
338        *  in the %multimap.  Iteration is done in ascending order according to
339        *  the keys.
340        */
341       const_iterator
342       begin() const _GLIBCXX_NOEXCEPT
343       { return _M_t.begin(); }
344 
345       /**
346        *  Returns a read/write iterator that points one past the last pair in
347        *  the %multimap.  Iteration is done in ascending order according to the
348        *  keys.
349        */
350       iterator
351       end() _GLIBCXX_NOEXCEPT
352       { return _M_t.end(); }
353 
354       /**
355        *  Returns a read-only (constant) iterator that points one past the last
356        *  pair in the %multimap.  Iteration is done in ascending order according
357        *  to the keys.
358        */
359       const_iterator
360       end() const _GLIBCXX_NOEXCEPT
361       { return _M_t.end(); }
362 
363       /**
364        *  Returns a read/write reverse iterator that points to the last pair in
365        *  the %multimap.  Iteration is done in descending order according to the
366        *  keys.
367        */
368       reverse_iterator
369       rbegin() _GLIBCXX_NOEXCEPT
370       { return _M_t.rbegin(); }
371 
372       /**
373        *  Returns a read-only (constant) reverse iterator that points to the
374        *  last pair in the %multimap.  Iteration is done in descending order
375        *  according to the keys.
376        */
377       const_reverse_iterator
378       rbegin() const _GLIBCXX_NOEXCEPT
379       { return _M_t.rbegin(); }
380 
381       /**
382        *  Returns a read/write reverse iterator that points to one before the
383        *  first pair in the %multimap.  Iteration is done in descending order
384        *  according to the keys.
385        */
386       reverse_iterator
387       rend() _GLIBCXX_NOEXCEPT
388       { return _M_t.rend(); }
389 
390       /**
391        *  Returns a read-only (constant) reverse iterator that points to one
392        *  before the first pair in the %multimap.  Iteration is done in
393        *  descending order according to the keys.
394        */
395       const_reverse_iterator
396       rend() const _GLIBCXX_NOEXCEPT
397       { return _M_t.rend(); }
398 
399 #if __cplusplus >= 201103L
400       /**
401        *  Returns a read-only (constant) iterator that points to the first pair
402        *  in the %multimap.  Iteration is done in ascending order according to
403        *  the keys.
404        */
405       const_iterator
406       cbegin() const noexcept
407       { return _M_t.begin(); }
408 
409       /**
410        *  Returns a read-only (constant) iterator that points one past the last
411        *  pair in the %multimap.  Iteration is done in ascending order according
412        *  to the keys.
413        */
414       const_iterator
415       cend() const noexcept
416       { return _M_t.end(); }
417 
418       /**
419        *  Returns a read-only (constant) reverse iterator that points to the
420        *  last pair in the %multimap.  Iteration is done in descending order
421        *  according to the keys.
422        */
423       const_reverse_iterator
424       crbegin() const noexcept
425       { return _M_t.rbegin(); }
426 
427       /**
428        *  Returns a read-only (constant) reverse iterator that points to one
429        *  before the first pair in the %multimap.  Iteration is done in
430        *  descending order according to the keys.
431        */
432       const_reverse_iterator
433       crend() const noexcept
434       { return _M_t.rend(); }
435 #endif
436 
437       // capacity
438       /** Returns true if the %multimap is empty.  */
439       bool
440       empty() const _GLIBCXX_NOEXCEPT
441       { return _M_t.empty(); }
442 
443       /** Returns the size of the %multimap.  */
444       size_type
445       size() const _GLIBCXX_NOEXCEPT
446       { return _M_t.size(); }
447 
448       /** Returns the maximum size of the %multimap.  */
449       size_type
450       max_size() const _GLIBCXX_NOEXCEPT
451       { return _M_t.max_size(); }
452 
453       // modifiers
454 #if __cplusplus >= 201103L
455       /**
456        *  @brief Build and insert a std::pair into the %multimap.
457        *
458        *  @param __args  Arguments used to generate a new pair instance (see
459        *	        std::piecewise_contruct for passing arguments to each
460        *	        part of the pair constructor).
461        *
462        *  @return An iterator that points to the inserted (key,value) pair.
463        *
464        *  This function builds and inserts a (key, value) %pair into the
465        *  %multimap.
466        *  Contrary to a std::map the %multimap does not rely on unique keys and
467        *  thus multiple pairs with the same key can be inserted.
468        *
469        *  Insertion requires logarithmic time.
470        */
471       template<typename... _Args>
472 	iterator
473 	emplace(_Args&&... __args)
474 	{ return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
475 
476       /**
477        *  @brief Builds and inserts a std::pair into the %multimap.
478        *
479        *  @param  __pos  An iterator that serves as a hint as to where the pair
480        *                should be inserted.
481        *  @param  __args  Arguments used to generate a new pair instance (see
482        *	         std::piecewise_contruct for passing arguments to each
483        *	         part of the pair constructor).
484        *  @return An iterator that points to the inserted (key,value) pair.
485        *
486        *  This function inserts a (key, value) pair into the %multimap.
487        *  Contrary to a std::map the %multimap does not rely on unique keys and
488        *  thus multiple pairs with the same key can be inserted.
489        *  Note that the first parameter is only a hint and can potentially
490        *  improve the performance of the insertion process.  A bad hint would
491        *  cause no gains in efficiency.
492        *
493        *  For more on @a hinting, see:
494        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
495        *
496        *  Insertion requires logarithmic time (if the hint is not taken).
497        */
498       template<typename... _Args>
499 	iterator
500 	emplace_hint(const_iterator __pos, _Args&&... __args)
501 	{
502 	  return _M_t._M_emplace_hint_equal(__pos,
503 					    std::forward<_Args>(__args)...);
504 	}
505 #endif
506 
507       /**
508        *  @brief Inserts a std::pair into the %multimap.
509        *  @param  __x  Pair to be inserted (see std::make_pair for easy creation
510        *             of pairs).
511        *  @return An iterator that points to the inserted (key,value) pair.
512        *
513        *  This function inserts a (key, value) pair into the %multimap.
514        *  Contrary to a std::map the %multimap does not rely on unique keys and
515        *  thus multiple pairs with the same key can be inserted.
516        *
517        *  Insertion requires logarithmic time.
518        */
519       iterator
520       insert(const value_type& __x)
521       { return _M_t._M_insert_equal(__x); }
522 
523 #if __cplusplus >= 201103L
524       template<typename _Pair, typename = typename
525 	       std::enable_if<std::is_constructible<value_type,
526 						    _Pair&&>::value>::type>
527         iterator
528         insert(_Pair&& __x)
529         { return _M_t._M_insert_equal(std::forward<_Pair>(__x)); }
530 #endif
531 
532       /**
533        *  @brief Inserts a std::pair into the %multimap.
534        *  @param  __position  An iterator that serves as a hint as to where the
535        *                      pair should be inserted.
536        *  @param  __x  Pair to be inserted (see std::make_pair for easy creation
537        *               of pairs).
538        *  @return An iterator that points to the inserted (key,value) pair.
539        *
540        *  This function inserts a (key, value) pair into the %multimap.
541        *  Contrary to a std::map the %multimap does not rely on unique keys and
542        *  thus multiple pairs with the same key can be inserted.
543        *  Note that the first parameter is only a hint and can potentially
544        *  improve the performance of the insertion process.  A bad hint would
545        *  cause no gains in efficiency.
546        *
547        *  For more on @a hinting, see:
548        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
549        *
550        *  Insertion requires logarithmic time (if the hint is not taken).
551        */
552       iterator
553 #if __cplusplus >= 201103L
554       insert(const_iterator __position, const value_type& __x)
555 #else
556       insert(iterator __position, const value_type& __x)
557 #endif
558       { return _M_t._M_insert_equal_(__position, __x); }
559 
560 #if __cplusplus >= 201103L
561       template<typename _Pair, typename = typename
562 	       std::enable_if<std::is_constructible<value_type,
563 						    _Pair&&>::value>::type>
564         iterator
565         insert(const_iterator __position, _Pair&& __x)
566         { return _M_t._M_insert_equal_(__position,
567 				       std::forward<_Pair>(__x)); }
568 #endif
569 
570       /**
571        *  @brief A template function that attempts to insert a range
572        *  of elements.
573        *  @param  __first  Iterator pointing to the start of the range to be
574        *                   inserted.
575        *  @param  __last  Iterator pointing to the end of the range.
576        *
577        *  Complexity similar to that of the range constructor.
578        */
579       template<typename _InputIterator>
580         void
581         insert(_InputIterator __first, _InputIterator __last)
582         { _M_t._M_insert_equal(__first, __last); }
583 
584 #if __cplusplus >= 201103L
585       /**
586        *  @brief Attempts to insert a list of std::pairs into the %multimap.
587        *  @param  __l  A std::initializer_list<value_type> of pairs to be
588        *               inserted.
589        *
590        *  Complexity similar to that of the range constructor.
591        */
592       void
593       insert(initializer_list<value_type> __l)
594       { this->insert(__l.begin(), __l.end()); }
595 #endif
596 
597 #if __cplusplus >= 201103L
598       // _GLIBCXX_RESOLVE_LIB_DEFECTS
599       // DR 130. Associative erase should return an iterator.
600       /**
601        *  @brief Erases an element from a %multimap.
602        *  @param  __position  An iterator pointing to the element to be erased.
603        *  @return An iterator pointing to the element immediately following
604        *          @a position prior to the element being erased. If no such
605        *          element exists, end() is returned.
606        *
607        *  This function erases an element, pointed to by the given iterator,
608        *  from a %multimap.  Note that this function only erases the element,
609        *  and that if the element is itself a pointer, the pointed-to memory is
610        *  not touched in any way.  Managing the pointer is the user's
611        *  responsibility.
612        */
613       iterator
614       erase(const_iterator __position)
615       { return _M_t.erase(__position); }
616 
617       // LWG 2059.
618       _GLIBCXX_ABI_TAG_CXX11
619       iterator
620       erase(iterator __position)
621       { return _M_t.erase(__position); }
622 #else
623       /**
624        *  @brief Erases an element from a %multimap.
625        *  @param  __position  An iterator pointing to the element to be erased.
626        *
627        *  This function erases an element, pointed to by the given iterator,
628        *  from a %multimap.  Note that this function only erases the element,
629        *  and that if the element is itself a pointer, the pointed-to memory is
630        *  not touched in any way.  Managing the pointer is the user's
631        *  responsibility.
632        */
633       void
634       erase(iterator __position)
635       { _M_t.erase(__position); }
636 #endif
637 
638       /**
639        *  @brief Erases elements according to the provided key.
640        *  @param  __x  Key of element to be erased.
641        *  @return  The number of elements erased.
642        *
643        *  This function erases all elements located by the given key from a
644        *  %multimap.
645        *  Note that this function only erases the element, and that if
646        *  the element is itself a pointer, the pointed-to memory is not touched
647        *  in any way.  Managing the pointer is the user's responsibility.
648        */
649       size_type
650       erase(const key_type& __x)
651       { return _M_t.erase(__x); }
652 
653 #if __cplusplus >= 201103L
654       // _GLIBCXX_RESOLVE_LIB_DEFECTS
655       // DR 130. Associative erase should return an iterator.
656       /**
657        *  @brief Erases a [first,last) range of elements from a %multimap.
658        *  @param  __first  Iterator pointing to the start of the range to be
659        *                   erased.
660        *  @param __last Iterator pointing to the end of the range to be
661        *                erased .
662        *  @return The iterator @a __last.
663        *
664        *  This function erases a sequence of elements from a %multimap.
665        *  Note that this function only erases the elements, and that if
666        *  the elements themselves are pointers, the pointed-to memory is not
667        *  touched in any way.  Managing the pointer is the user's
668        *  responsibility.
669        */
670       iterator
671       erase(const_iterator __first, const_iterator __last)
672       { return _M_t.erase(__first, __last); }
673 #else
674       // _GLIBCXX_RESOLVE_LIB_DEFECTS
675       // DR 130. Associative erase should return an iterator.
676       /**
677        *  @brief Erases a [first,last) range of elements from a %multimap.
678        *  @param  __first  Iterator pointing to the start of the range to be
679        *                 erased.
680        *  @param __last Iterator pointing to the end of the range to
681        *                be erased.
682        *
683        *  This function erases a sequence of elements from a %multimap.
684        *  Note that this function only erases the elements, and that if
685        *  the elements themselves are pointers, the pointed-to memory is not
686        *  touched in any way.  Managing the pointer is the user's
687        *  responsibility.
688        */
689       void
690       erase(iterator __first, iterator __last)
691       { _M_t.erase(__first, __last); }
692 #endif
693 
694       /**
695        *  @brief  Swaps data with another %multimap.
696        *  @param  __x  A %multimap of the same element and allocator types.
697        *
698        *  This exchanges the elements between two multimaps in constant time.
699        *  (It is only swapping a pointer, an integer, and an instance of
700        *  the @c Compare type (which itself is often stateless and empty), so it
701        *  should be quite fast.)
702        *  Note that the global std::swap() function is specialized such that
703        *  std::swap(m1,m2) will feed to this function.
704        */
705       void
706       swap(multimap& __x)
707       _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
708       { _M_t.swap(__x._M_t); }
709 
710       /**
711        *  Erases all elements in a %multimap.  Note that this function only
712        *  erases the elements, and that if the elements themselves are pointers,
713        *  the pointed-to memory is not touched in any way.  Managing the pointer
714        *  is the user's responsibility.
715        */
716       void
717       clear() _GLIBCXX_NOEXCEPT
718       { _M_t.clear(); }
719 
720       // observers
721       /**
722        *  Returns the key comparison object out of which the %multimap
723        *  was constructed.
724        */
725       key_compare
726       key_comp() const
727       { return _M_t.key_comp(); }
728 
729       /**
730        *  Returns a value comparison object, built from the key comparison
731        *  object out of which the %multimap was constructed.
732        */
733       value_compare
734       value_comp() const
735       { return value_compare(_M_t.key_comp()); }
736 
737       // multimap operations
738 
739       //@{
740       /**
741        *  @brief Tries to locate an element in a %multimap.
742        *  @param  __x  Key of (key, value) pair to be located.
743        *  @return  Iterator pointing to sought-after element,
744        *           or end() if not found.
745        *
746        *  This function takes a key and tries to locate the element with which
747        *  the key matches.  If successful the function returns an iterator
748        *  pointing to the sought after %pair.  If unsuccessful it returns the
749        *  past-the-end ( @c end() ) iterator.
750        */
751       iterator
752       find(const key_type& __x)
753       { return _M_t.find(__x); }
754 
755 #if __cplusplus > 201103L
756       template<typename _Kt>
757 	auto
758 	find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
759 	{ return _M_t._M_find_tr(__x); }
760 #endif
761       //@}
762 
763       //@{
764       /**
765        *  @brief Tries to locate an element in a %multimap.
766        *  @param  __x  Key of (key, value) pair to be located.
767        *  @return  Read-only (constant) iterator pointing to sought-after
768        *           element, or end() if not found.
769        *
770        *  This function takes a key and tries to locate the element with which
771        *  the key matches.  If successful the function returns a constant
772        *  iterator pointing to the sought after %pair.  If unsuccessful it
773        *  returns the past-the-end ( @c end() ) iterator.
774        */
775       const_iterator
776       find(const key_type& __x) const
777       { return _M_t.find(__x); }
778 
779 #if __cplusplus > 201103L
780       template<typename _Kt>
781 	auto
782 	find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
783 	{ return _M_t._M_find_tr(__x); }
784 #endif
785       //@}
786 
787       //@{
788       /**
789        *  @brief Finds the number of elements with given key.
790        *  @param  __x  Key of (key, value) pairs to be located.
791        *  @return Number of elements with specified key.
792        */
793       size_type
794       count(const key_type& __x) const
795       { return _M_t.count(__x); }
796 
797 #if __cplusplus > 201103L
798       template<typename _Kt>
799 	auto
800 	count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
801 	{ return _M_t._M_count_tr(__x); }
802 #endif
803       //@}
804 
805       //@{
806       /**
807        *  @brief Finds the beginning of a subsequence matching given key.
808        *  @param  __x  Key of (key, value) pair to be located.
809        *  @return  Iterator pointing to first element equal to or greater
810        *           than key, or end().
811        *
812        *  This function returns the first element of a subsequence of elements
813        *  that matches the given key.  If unsuccessful it returns an iterator
814        *  pointing to the first element that has a greater value than given key
815        *  or end() if no such element exists.
816        */
817       iterator
818       lower_bound(const key_type& __x)
819       { return _M_t.lower_bound(__x); }
820 
821 #if __cplusplus > 201103L
822       template<typename _Kt>
823 	auto
824 	lower_bound(const _Kt& __x)
825 	-> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
826 	{ return iterator(_M_t._M_lower_bound_tr(__x)); }
827 #endif
828       //@}
829 
830       //@{
831       /**
832        *  @brief Finds the beginning of a subsequence matching given key.
833        *  @param  __x  Key of (key, value) pair to be located.
834        *  @return  Read-only (constant) iterator pointing to first element
835        *           equal to or greater than key, or end().
836        *
837        *  This function returns the first element of a subsequence of
838        *  elements that matches the given key.  If unsuccessful the
839        *  iterator will point to the next greatest element or, if no
840        *  such greater element exists, to end().
841        */
842       const_iterator
843       lower_bound(const key_type& __x) const
844       { return _M_t.lower_bound(__x); }
845 
846 #if __cplusplus > 201103L
847       template<typename _Kt>
848 	auto
849 	lower_bound(const _Kt& __x) const
850 	-> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
851 	{ return const_iterator(_M_t._M_lower_bound_tr(__x)); }
852 #endif
853       //@}
854 
855       //@{
856       /**
857        *  @brief Finds the end of a subsequence matching given key.
858        *  @param  __x  Key of (key, value) pair to be located.
859        *  @return Iterator pointing to the first element
860        *          greater than key, or end().
861        */
862       iterator
863       upper_bound(const key_type& __x)
864       { return _M_t.upper_bound(__x); }
865 
866 #if __cplusplus > 201103L
867       template<typename _Kt>
868 	auto
869 	upper_bound(const _Kt& __x)
870 	-> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
871 	{ return iterator(_M_t._M_upper_bound_tr(__x)); }
872 #endif
873       //@}
874 
875       //@{
876       /**
877        *  @brief Finds the end of a subsequence matching given key.
878        *  @param  __x  Key of (key, value) pair to be located.
879        *  @return  Read-only (constant) iterator pointing to first iterator
880        *           greater than key, or end().
881        */
882       const_iterator
883       upper_bound(const key_type& __x) const
884       { return _M_t.upper_bound(__x); }
885 
886 #if __cplusplus > 201103L
887       template<typename _Kt>
888 	auto
889 	upper_bound(const _Kt& __x) const
890 	-> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
891 	{ return const_iterator(_M_t._M_upper_bound_tr(__x)); }
892 #endif
893       //@}
894 
895       //@{
896       /**
897        *  @brief Finds a subsequence matching given key.
898        *  @param  __x  Key of (key, value) pairs to be located.
899        *  @return  Pair of iterators that possibly points to the subsequence
900        *           matching given key.
901        *
902        *  This function is equivalent to
903        *  @code
904        *    std::make_pair(c.lower_bound(val),
905        *                   c.upper_bound(val))
906        *  @endcode
907        *  (but is faster than making the calls separately).
908        */
909       std::pair<iterator, iterator>
910       equal_range(const key_type& __x)
911       { return _M_t.equal_range(__x); }
912 
913 #if __cplusplus > 201103L
914       template<typename _Kt>
915 	auto
916 	equal_range(const _Kt& __x)
917 	-> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
918 	{ return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
919 #endif
920       //@}
921 
922       //@{
923       /**
924        *  @brief Finds a subsequence matching given key.
925        *  @param  __x  Key of (key, value) pairs to be located.
926        *  @return  Pair of read-only (constant) iterators that possibly points
927        *           to the subsequence matching given key.
928        *
929        *  This function is equivalent to
930        *  @code
931        *    std::make_pair(c.lower_bound(val),
932        *                   c.upper_bound(val))
933        *  @endcode
934        *  (but is faster than making the calls separately).
935        */
936       std::pair<const_iterator, const_iterator>
937       equal_range(const key_type& __x) const
938       { return _M_t.equal_range(__x); }
939 
940 #if __cplusplus > 201103L
941       template<typename _Kt>
942 	auto
943 	equal_range(const _Kt& __x) const
944 	-> decltype(pair<const_iterator, const_iterator>(
945 	      _M_t._M_equal_range_tr(__x)))
946 	{
947 	  return pair<const_iterator, const_iterator>(
948 	      _M_t._M_equal_range_tr(__x));
949 	}
950 #endif
951       //@}
952 
953       template<typename _K1, typename _T1, typename _C1, typename _A1>
954         friend bool
955         operator==(const multimap<_K1, _T1, _C1, _A1>&,
956 		   const multimap<_K1, _T1, _C1, _A1>&);
957 
958       template<typename _K1, typename _T1, typename _C1, typename _A1>
959         friend bool
960         operator<(const multimap<_K1, _T1, _C1, _A1>&,
961 		  const multimap<_K1, _T1, _C1, _A1>&);
962   };
963 
964   /**
965    *  @brief  Multimap equality comparison.
966    *  @param  __x  A %multimap.
967    *  @param  __y  A %multimap of the same type as @a __x.
968    *  @return  True iff the size and elements of the maps are equal.
969    *
970    *  This is an equivalence relation.  It is linear in the size of the
971    *  multimaps.  Multimaps are considered equivalent if their sizes are equal,
972    *  and if corresponding elements compare equal.
973   */
974   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
975     inline bool
976     operator==(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
977                const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
978     { return __x._M_t == __y._M_t; }
979 
980   /**
981    *  @brief  Multimap ordering relation.
982    *  @param  __x  A %multimap.
983    *  @param  __y  A %multimap of the same type as @a __x.
984    *  @return  True iff @a x is lexicographically less than @a y.
985    *
986    *  This is a total ordering relation.  It is linear in the size of the
987    *  multimaps.  The elements must be comparable with @c <.
988    *
989    *  See std::lexicographical_compare() for how the determination is made.
990   */
991   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
992     inline bool
993     operator<(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
994               const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
995     { return __x._M_t < __y._M_t; }
996 
997   /// Based on operator==
998   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
999     inline bool
1000     operator!=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1001                const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1002     { return !(__x == __y); }
1003 
1004   /// Based on operator<
1005   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1006     inline bool
1007     operator>(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1008               const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1009     { return __y < __x; }
1010 
1011   /// Based on operator<
1012   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1013     inline bool
1014     operator<=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1015                const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1016     { return !(__y < __x); }
1017 
1018   /// Based on operator<
1019   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1020     inline bool
1021     operator>=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1022                const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1023     { return !(__x < __y); }
1024 
1025   /// See std::multimap::swap().
1026   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
1027     inline void
1028     swap(multimap<_Key, _Tp, _Compare, _Alloc>& __x,
1029          multimap<_Key, _Tp, _Compare, _Alloc>& __y)
1030     _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
1031     { __x.swap(__y); }
1032 
1033 _GLIBCXX_END_NAMESPACE_CONTAINER
1034 } // namespace std
1035 
1036 #endif /* _STL_MULTIMAP_H */
1037