libstdc++
stl_multiset.h
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00001 // Multiset implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001-2019 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /*
00026  *
00027  * Copyright (c) 1994
00028  * Hewlett-Packard Company
00029  *
00030  * Permission to use, copy, modify, distribute and sell this software
00031  * and its documentation for any purpose is hereby granted without fee,
00032  * provided that the above copyright notice appear in all copies and
00033  * that both that copyright notice and this permission notice appear
00034  * in supporting documentation.  Hewlett-Packard Company makes no
00035  * representations about the suitability of this software for any
00036  * purpose.  It is provided "as is" without express or implied warranty.
00037  *
00038  *
00039  * Copyright (c) 1996
00040  * Silicon Graphics Computer Systems, Inc.
00041  *
00042  * Permission to use, copy, modify, distribute and sell this software
00043  * and its documentation for any purpose is hereby granted without fee,
00044  * provided that the above copyright notice appear in all copies and
00045  * that both that copyright notice and this permission notice appear
00046  * in supporting documentation.  Silicon Graphics makes no
00047  * representations about the suitability of this software for any
00048  * purpose.  It is provided "as is" without express or implied warranty.
00049  */
00050 
00051 /** @file bits/stl_multiset.h
00052  *  This is an internal header file, included by other library headers.
00053  *  Do not attempt to use it directly. @headername{set}
00054  */
00055 
00056 #ifndef _STL_MULTISET_H
00057 #define _STL_MULTISET_H 1
00058 
00059 #include <bits/concept_check.h>
00060 #if __cplusplus >= 201103L
00061 #include <initializer_list>
00062 #endif
00063 
00064 namespace std _GLIBCXX_VISIBILITY(default)
00065 {
00066 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00067 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
00068 
00069   template<typename _Key, typename _Compare, typename _Alloc>
00070     class set;
00071 
00072   /**
00073    *  @brief A standard container made up of elements, which can be retrieved
00074    *  in logarithmic time.
00075    *
00076    *  @ingroup associative_containers
00077    *
00078    *
00079    *  @tparam _Key  Type of key objects.
00080    *  @tparam _Compare  Comparison function object type, defaults to less<_Key>.
00081    *  @tparam _Alloc  Allocator type, defaults to allocator<_Key>.
00082    *
00083    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
00084    *  <a href="tables.html#66">reversible container</a>, and an
00085    *  <a href="tables.html#69">associative container</a> (using equivalent
00086    *  keys).  For a @c multiset<Key> the key_type and value_type are Key.
00087    *
00088    *  Multisets support bidirectional iterators.
00089    *
00090    *  The private tree data is declared exactly the same way for set and
00091    *  multiset; the distinction is made entirely in how the tree functions are
00092    *  called (*_unique versus *_equal, same as the standard).
00093   */
00094   template <typename _Key, typename _Compare = std::less<_Key>,
00095             typename _Alloc = std::allocator<_Key> >
00096     class multiset
00097     {
00098 #ifdef _GLIBCXX_CONCEPT_CHECKS
00099       // concept requirements
00100       typedef typename _Alloc::value_type               _Alloc_value_type;
00101 # if __cplusplus < 201103L
00102       __glibcxx_class_requires(_Key, _SGIAssignableConcept)
00103 # endif
00104       __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
00105                                 _BinaryFunctionConcept)
00106       __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept)
00107 #endif
00108 
00109 #if __cplusplus >= 201103L
00110       static_assert(is_same<typename remove_cv<_Key>::type, _Key>::value,
00111           "std::multiset must have a non-const, non-volatile value_type");
00112 # ifdef __STRICT_ANSI__
00113       static_assert(is_same<typename _Alloc::value_type, _Key>::value,
00114           "std::multiset must have the same value_type as its allocator");
00115 # endif
00116 #endif
00117 
00118     public:
00119       // typedefs:
00120       typedef _Key     key_type;
00121       typedef _Key     value_type;
00122       typedef _Compare key_compare;
00123       typedef _Compare value_compare;
00124       typedef _Alloc   allocator_type;
00125 
00126     private:
00127       /// This turns a red-black tree into a [multi]set.
00128       typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
00129         rebind<_Key>::other _Key_alloc_type;
00130 
00131       typedef _Rb_tree<key_type, value_type, _Identity<value_type>,
00132                        key_compare, _Key_alloc_type> _Rep_type;
00133       /// The actual tree structure.
00134       _Rep_type _M_t;
00135 
00136       typedef __gnu_cxx::__alloc_traits<_Key_alloc_type> _Alloc_traits;
00137 
00138     public:
00139       typedef typename _Alloc_traits::pointer            pointer;
00140       typedef typename _Alloc_traits::const_pointer      const_pointer;
00141       typedef typename _Alloc_traits::reference          reference;
00142       typedef typename _Alloc_traits::const_reference    const_reference;
00143       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00144       // DR 103. set::iterator is required to be modifiable,
00145       // but this allows modification of keys.
00146       typedef typename _Rep_type::const_iterator         iterator;
00147       typedef typename _Rep_type::const_iterator         const_iterator;
00148       typedef typename _Rep_type::const_reverse_iterator reverse_iterator;
00149       typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
00150       typedef typename _Rep_type::size_type              size_type;
00151       typedef typename _Rep_type::difference_type        difference_type;
00152 
00153 #if __cplusplus > 201402L
00154       using node_type = typename _Rep_type::node_type;
00155 #endif
00156 
00157       // allocation/deallocation
00158       /**
00159        *  @brief  Default constructor creates no elements.
00160        */
00161 #if __cplusplus < 201103L
00162       multiset() : _M_t() { }
00163 #else
00164       multiset() = default;
00165 #endif
00166 
00167       /**
00168        *  @brief  Creates a %multiset with no elements.
00169        *  @param  __comp  Comparator to use.
00170        *  @param  __a  An allocator object.
00171        */
00172       explicit
00173       multiset(const _Compare& __comp,
00174                const allocator_type& __a = allocator_type())
00175       : _M_t(__comp, _Key_alloc_type(__a)) { }
00176 
00177       /**
00178        *  @brief  Builds a %multiset from a range.
00179        *  @param  __first  An input iterator.
00180        *  @param  __last  An input iterator.
00181        *
00182        *  Create a %multiset consisting of copies of the elements from
00183        *  [first,last).  This is linear in N if the range is already sorted,
00184        *  and NlogN otherwise (where N is distance(__first,__last)).
00185        */
00186       template<typename _InputIterator>
00187         multiset(_InputIterator __first, _InputIterator __last)
00188         : _M_t()
00189         { _M_t._M_insert_range_equal(__first, __last); }
00190 
00191       /**
00192        *  @brief  Builds a %multiset from a range.
00193        *  @param  __first  An input iterator.
00194        *  @param  __last  An input iterator.
00195        *  @param  __comp  A comparison functor.
00196        *  @param  __a  An allocator object.
00197        *
00198        *  Create a %multiset consisting of copies of the elements from
00199        *  [__first,__last).  This is linear in N if the range is already sorted,
00200        *  and NlogN otherwise (where N is distance(__first,__last)).
00201        */
00202       template<typename _InputIterator>
00203         multiset(_InputIterator __first, _InputIterator __last,
00204                  const _Compare& __comp,
00205                  const allocator_type& __a = allocator_type())
00206         : _M_t(__comp, _Key_alloc_type(__a))
00207         { _M_t._M_insert_range_equal(__first, __last); }
00208 
00209       /**
00210        *  @brief  %Multiset copy constructor.
00211        *
00212        *  Whether the allocator is copied depends on the allocator traits.
00213        */
00214 #if __cplusplus < 201103L
00215       multiset(const multiset& __x)
00216       : _M_t(__x._M_t) { }
00217 #else
00218       multiset(const multiset&) = default;
00219 
00220      /**
00221        *  @brief  %Multiset move constructor.
00222        *
00223        *  The newly-created %multiset contains the exact contents of the
00224        *  moved instance. The moved instance is a valid, but unspecified
00225        *  %multiset.
00226        */
00227       multiset(multiset&&) = default;
00228 
00229       /**
00230        *  @brief  Builds a %multiset from an initializer_list.
00231        *  @param  __l  An initializer_list.
00232        *  @param  __comp  A comparison functor.
00233        *  @param  __a  An allocator object.
00234        *
00235        *  Create a %multiset consisting of copies of the elements from
00236        *  the list.  This is linear in N if the list is already sorted,
00237        *  and NlogN otherwise (where N is @a __l.size()).
00238        */
00239       multiset(initializer_list<value_type> __l,
00240                const _Compare& __comp = _Compare(),
00241                const allocator_type& __a = allocator_type())
00242       : _M_t(__comp, _Key_alloc_type(__a))
00243       { _M_t._M_insert_range_equal(__l.begin(), __l.end()); }
00244 
00245       /// Allocator-extended default constructor.
00246       explicit
00247       multiset(const allocator_type& __a)
00248       : _M_t(_Key_alloc_type(__a)) { }
00249 
00250       /// Allocator-extended copy constructor.
00251       multiset(const multiset& __m, const allocator_type& __a)
00252       : _M_t(__m._M_t, _Key_alloc_type(__a)) { }
00253 
00254       /// Allocator-extended move constructor.
00255       multiset(multiset&& __m, const allocator_type& __a)
00256       noexcept(is_nothrow_copy_constructible<_Compare>::value
00257                && _Alloc_traits::_S_always_equal())
00258       : _M_t(std::move(__m._M_t), _Key_alloc_type(__a)) { }
00259 
00260       /// Allocator-extended initialier-list constructor.
00261       multiset(initializer_list<value_type> __l, const allocator_type& __a)
00262       : _M_t(_Key_alloc_type(__a))
00263       { _M_t._M_insert_range_equal(__l.begin(), __l.end()); }
00264 
00265       /// Allocator-extended range constructor.
00266       template<typename _InputIterator>
00267         multiset(_InputIterator __first, _InputIterator __last,
00268                  const allocator_type& __a)
00269         : _M_t(_Key_alloc_type(__a))
00270         { _M_t._M_insert_range_equal(__first, __last); }
00271 
00272       /**
00273        *  The dtor only erases the elements, and note that if the elements
00274        *  themselves are pointers, the pointed-to memory is not touched in any
00275        *  way. Managing the pointer is the user's responsibility.
00276        */
00277       ~multiset() = default;
00278 #endif
00279 
00280       /**
00281        *  @brief  %Multiset assignment operator.
00282        *
00283        *  Whether the allocator is copied depends on the allocator traits.
00284        */
00285 #if __cplusplus < 201103L
00286       multiset&
00287       operator=(const multiset& __x)
00288       {
00289         _M_t = __x._M_t;
00290         return *this;
00291       }
00292 #else
00293       multiset&
00294       operator=(const multiset&) = default;
00295 
00296       /// Move assignment operator.
00297       multiset&
00298       operator=(multiset&&) = default;
00299 
00300       /**
00301        *  @brief  %Multiset list assignment operator.
00302        *  @param  __l  An initializer_list.
00303        *
00304        *  This function fills a %multiset with copies of the elements in the
00305        *  initializer list @a __l.
00306        *
00307        *  Note that the assignment completely changes the %multiset and
00308        *  that the resulting %multiset's size is the same as the number
00309        *  of elements assigned.
00310        */
00311       multiset&
00312       operator=(initializer_list<value_type> __l)
00313       {
00314         _M_t._M_assign_equal(__l.begin(), __l.end());
00315         return *this;
00316       }
00317 #endif
00318 
00319       // accessors:
00320 
00321       ///  Returns the comparison object.
00322       key_compare
00323       key_comp() const
00324       { return _M_t.key_comp(); }
00325       ///  Returns the comparison object.
00326       value_compare
00327       value_comp() const
00328       { return _M_t.key_comp(); }
00329       ///  Returns the memory allocation object.
00330       allocator_type
00331       get_allocator() const _GLIBCXX_NOEXCEPT
00332       { return allocator_type(_M_t.get_allocator()); }
00333 
00334       /**
00335        *  Returns a read-only (constant) iterator that points to the first
00336        *  element in the %multiset.  Iteration is done in ascending order
00337        *  according to the keys.
00338        */
00339       iterator
00340       begin() const _GLIBCXX_NOEXCEPT
00341       { return _M_t.begin(); }
00342 
00343       /**
00344        *  Returns a read-only (constant) iterator that points one past the last
00345        *  element in the %multiset.  Iteration is done in ascending order
00346        *  according to the keys.
00347        */
00348       iterator
00349       end() const _GLIBCXX_NOEXCEPT
00350       { return _M_t.end(); }
00351 
00352       /**
00353        *  Returns a read-only (constant) reverse iterator that points to the
00354        *  last element in the %multiset.  Iteration is done in descending order
00355        *  according to the keys.
00356        */
00357       reverse_iterator
00358       rbegin() const _GLIBCXX_NOEXCEPT
00359       { return _M_t.rbegin(); }
00360 
00361       /**
00362        *  Returns a read-only (constant) reverse iterator that points to the
00363        *  last element in the %multiset.  Iteration is done in descending order
00364        *  according to the keys.
00365        */
00366       reverse_iterator
00367       rend() const _GLIBCXX_NOEXCEPT
00368       { return _M_t.rend(); }
00369 
00370 #if __cplusplus >= 201103L
00371       /**
00372        *  Returns a read-only (constant) iterator that points to the first
00373        *  element in the %multiset.  Iteration is done in ascending order
00374        *  according to the keys.
00375        */
00376       iterator
00377       cbegin() const noexcept
00378       { return _M_t.begin(); }
00379 
00380       /**
00381        *  Returns a read-only (constant) iterator that points one past the last
00382        *  element in the %multiset.  Iteration is done in ascending order
00383        *  according to the keys.
00384        */
00385       iterator
00386       cend() const noexcept
00387       { return _M_t.end(); }
00388 
00389       /**
00390        *  Returns a read-only (constant) reverse iterator that points to the
00391        *  last element in the %multiset.  Iteration is done in descending order
00392        *  according to the keys.
00393        */
00394       reverse_iterator
00395       crbegin() const noexcept
00396       { return _M_t.rbegin(); }
00397 
00398       /**
00399        *  Returns a read-only (constant) reverse iterator that points to the
00400        *  last element in the %multiset.  Iteration is done in descending order
00401        *  according to the keys.
00402        */
00403       reverse_iterator
00404       crend() const noexcept
00405       { return _M_t.rend(); }
00406 #endif
00407 
00408       ///  Returns true if the %set is empty.
00409       _GLIBCXX_NODISCARD bool
00410       empty() const _GLIBCXX_NOEXCEPT
00411       { return _M_t.empty(); }
00412 
00413       ///  Returns the size of the %set.
00414       size_type
00415       size() const _GLIBCXX_NOEXCEPT
00416       { return _M_t.size(); }
00417 
00418       ///  Returns the maximum size of the %set.
00419       size_type
00420       max_size() const _GLIBCXX_NOEXCEPT
00421       { return _M_t.max_size(); }
00422 
00423       /**
00424        *  @brief  Swaps data with another %multiset.
00425        *  @param  __x  A %multiset of the same element and allocator types.
00426        *
00427        *  This exchanges the elements between two multisets in constant time.
00428        *  (It is only swapping a pointer, an integer, and an instance of the @c
00429        *  Compare type (which itself is often stateless and empty), so it should
00430        *  be quite fast.)
00431        *  Note that the global std::swap() function is specialized such that
00432        *  std::swap(s1,s2) will feed to this function.
00433        *
00434        *  Whether the allocators are swapped depends on the allocator traits.
00435        */
00436       void
00437       swap(multiset& __x)
00438       _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
00439       { _M_t.swap(__x._M_t); }
00440 
00441       // insert/erase
00442 #if __cplusplus >= 201103L
00443       /**
00444        *  @brief Builds and inserts an element into the %multiset.
00445        *  @param  __args  Arguments used to generate the element instance to be
00446        *                 inserted.
00447        *  @return An iterator that points to the inserted element.
00448        *
00449        *  This function inserts an element into the %multiset.  Contrary
00450        *  to a std::set the %multiset does not rely on unique keys and thus
00451        *  multiple copies of the same element can be inserted.
00452        *
00453        *  Insertion requires logarithmic time.
00454        */
00455       template<typename... _Args>
00456         iterator
00457         emplace(_Args&&... __args)
00458         { return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
00459 
00460       /**
00461        *  @brief Builds and inserts an element into the %multiset.
00462        *  @param  __pos  An iterator that serves as a hint as to where the
00463        *                element should be inserted.
00464        *  @param  __args  Arguments used to generate the element instance to be
00465        *                 inserted.
00466        *  @return An iterator that points to the inserted element.
00467        *
00468        *  This function inserts an element into the %multiset.  Contrary
00469        *  to a std::set the %multiset does not rely on unique keys and thus
00470        *  multiple copies of the same element can be inserted.
00471        *
00472        *  Note that the first parameter is only a hint and can potentially
00473        *  improve the performance of the insertion process.  A bad hint would
00474        *  cause no gains in efficiency.
00475        *
00476        *  See https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00477        *  for more on @a hinting.
00478        *
00479        *  Insertion requires logarithmic time (if the hint is not taken).
00480        */
00481       template<typename... _Args>
00482         iterator
00483         emplace_hint(const_iterator __pos, _Args&&... __args)
00484         {
00485           return _M_t._M_emplace_hint_equal(__pos,
00486                                             std::forward<_Args>(__args)...);
00487         }
00488 #endif
00489 
00490       /**
00491        *  @brief Inserts an element into the %multiset.
00492        *  @param  __x  Element to be inserted.
00493        *  @return An iterator that points to the inserted element.
00494        *
00495        *  This function inserts an element into the %multiset.  Contrary
00496        *  to a std::set the %multiset does not rely on unique keys and thus
00497        *  multiple copies of the same element can be inserted.
00498        *
00499        *  Insertion requires logarithmic time.
00500        */
00501       iterator
00502       insert(const value_type& __x)
00503       { return _M_t._M_insert_equal(__x); }
00504 
00505 #if __cplusplus >= 201103L
00506       iterator
00507       insert(value_type&& __x)
00508       { return _M_t._M_insert_equal(std::move(__x)); }
00509 #endif
00510 
00511       /**
00512        *  @brief Inserts an element into the %multiset.
00513        *  @param  __position  An iterator that serves as a hint as to where the
00514        *                    element should be inserted.
00515        *  @param  __x  Element to be inserted.
00516        *  @return An iterator that points to the inserted element.
00517        *
00518        *  This function inserts an element into the %multiset.  Contrary
00519        *  to a std::set the %multiset does not rely on unique keys and thus
00520        *  multiple copies of the same element can be inserted.
00521        *
00522        *  Note that the first parameter is only a hint and can potentially
00523        *  improve the performance of the insertion process.  A bad hint would
00524        *  cause no gains in efficiency.
00525        *
00526        *  See https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00527        *  for more on @a hinting.
00528        *
00529        *  Insertion requires logarithmic time (if the hint is not taken).
00530        */
00531       iterator
00532       insert(const_iterator __position, const value_type& __x)
00533       { return _M_t._M_insert_equal_(__position, __x); }
00534 
00535 #if __cplusplus >= 201103L
00536       iterator
00537       insert(const_iterator __position, value_type&& __x)
00538       { return _M_t._M_insert_equal_(__position, std::move(__x)); }
00539 #endif
00540 
00541       /**
00542        *  @brief A template function that tries to insert a range of elements.
00543        *  @param  __first  Iterator pointing to the start of the range to be
00544        *                   inserted.
00545        *  @param  __last  Iterator pointing to the end of the range.
00546        *
00547        *  Complexity similar to that of the range constructor.
00548        */
00549       template<typename _InputIterator>
00550         void
00551         insert(_InputIterator __first, _InputIterator __last)
00552         { _M_t._M_insert_range_equal(__first, __last); }
00553 
00554 #if __cplusplus >= 201103L
00555       /**
00556        *  @brief Attempts to insert a list of elements into the %multiset.
00557        *  @param  __l  A std::initializer_list<value_type> of elements
00558        *               to be inserted.
00559        *
00560        *  Complexity similar to that of the range constructor.
00561        */
00562       void
00563       insert(initializer_list<value_type> __l)
00564       { this->insert(__l.begin(), __l.end()); }
00565 #endif
00566 
00567 #if __cplusplus > 201402L
00568       /// Extract a node.
00569       node_type
00570       extract(const_iterator __pos)
00571       {
00572         __glibcxx_assert(__pos != end());
00573         return _M_t.extract(__pos);
00574       }
00575 
00576       /// Extract a node.
00577       node_type
00578       extract(const key_type& __x)
00579       { return _M_t.extract(__x); }
00580 
00581       /// Re-insert an extracted node.
00582       iterator
00583       insert(node_type&& __nh)
00584       { return _M_t._M_reinsert_node_equal(std::move(__nh)); }
00585 
00586       /// Re-insert an extracted node.
00587       iterator
00588       insert(const_iterator __hint, node_type&& __nh)
00589       { return _M_t._M_reinsert_node_hint_equal(__hint, std::move(__nh)); }
00590 
00591       template<typename, typename>
00592         friend class std::_Rb_tree_merge_helper;
00593 
00594       template<typename _Compare1>
00595         void
00596         merge(multiset<_Key, _Compare1, _Alloc>& __source)
00597         {
00598           using _Merge_helper = _Rb_tree_merge_helper<multiset, _Compare1>;
00599           _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
00600         }
00601 
00602       template<typename _Compare1>
00603         void
00604         merge(multiset<_Key, _Compare1, _Alloc>&& __source)
00605         { merge(__source); }
00606 
00607       template<typename _Compare1>
00608         void
00609         merge(set<_Key, _Compare1, _Alloc>& __source)
00610         {
00611           using _Merge_helper = _Rb_tree_merge_helper<multiset, _Compare1>;
00612           _M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
00613         }
00614 
00615       template<typename _Compare1>
00616         void
00617         merge(set<_Key, _Compare1, _Alloc>&& __source)
00618         { merge(__source); }
00619 #endif // C++17
00620 
00621 #if __cplusplus >= 201103L
00622       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00623       // DR 130. Associative erase should return an iterator.
00624       /**
00625        *  @brief Erases an element from a %multiset.
00626        *  @param  __position  An iterator pointing to the element to be erased.
00627        *  @return An iterator pointing to the element immediately following
00628        *          @a position prior to the element being erased. If no such
00629        *          element exists, end() is returned.
00630        *
00631        *  This function erases an element, pointed to by the given iterator,
00632        *  from a %multiset.  Note that this function only erases the element,
00633        *  and that if the element is itself a pointer, the pointed-to memory is
00634        *  not touched in any way.  Managing the pointer is the user's
00635        *  responsibility.
00636        */
00637       _GLIBCXX_ABI_TAG_CXX11
00638       iterator
00639       erase(const_iterator __position)
00640       { return _M_t.erase(__position); }
00641 #else
00642       /**
00643        *  @brief Erases an element from a %multiset.
00644        *  @param  __position  An iterator pointing to the element to be erased.
00645        *
00646        *  This function erases an element, pointed to by the given iterator,
00647        *  from a %multiset.  Note that this function only erases the element,
00648        *  and that if the element is itself a pointer, the pointed-to memory is
00649        *  not touched in any way.  Managing the pointer is the user's
00650        *  responsibility.
00651        */
00652       void
00653       erase(iterator __position)
00654       { _M_t.erase(__position); }
00655 #endif
00656 
00657       /**
00658        *  @brief Erases elements according to the provided key.
00659        *  @param  __x  Key of element to be erased.
00660        *  @return  The number of elements erased.
00661        *
00662        *  This function erases all elements located by the given key from a
00663        *  %multiset.
00664        *  Note that this function only erases the element, and that if
00665        *  the element is itself a pointer, the pointed-to memory is not touched
00666        *  in any way.  Managing the pointer is the user's responsibility.
00667        */
00668       size_type
00669       erase(const key_type& __x)
00670       { return _M_t.erase(__x); }
00671 
00672 #if __cplusplus >= 201103L
00673       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00674       // DR 130. Associative erase should return an iterator.
00675       /**
00676        *  @brief Erases a [first,last) range of elements from a %multiset.
00677        *  @param  __first  Iterator pointing to the start of the range to be
00678        *                   erased.
00679        *  @param __last Iterator pointing to the end of the range to
00680        *                be erased.
00681        *  @return The iterator @a last.
00682        *
00683        *  This function erases a sequence of elements from a %multiset.
00684        *  Note that this function only erases the elements, and that if
00685        *  the elements themselves are pointers, the pointed-to memory is not
00686        *  touched in any way.  Managing the pointer is the user's
00687        *  responsibility.
00688        */
00689       _GLIBCXX_ABI_TAG_CXX11
00690       iterator
00691       erase(const_iterator __first, const_iterator __last)
00692       { return _M_t.erase(__first, __last); }
00693 #else
00694       /**
00695        *  @brief Erases a [first,last) range of elements from a %multiset.
00696        *  @param  first  Iterator pointing to the start of the range to be
00697        *                 erased.
00698        *  @param  last  Iterator pointing to the end of the range to be erased.
00699        *
00700        *  This function erases a sequence of elements from a %multiset.
00701        *  Note that this function only erases the elements, and that if
00702        *  the elements themselves are pointers, the pointed-to memory is not
00703        *  touched in any way.  Managing the pointer is the user's
00704        *  responsibility.
00705        */
00706       void
00707       erase(iterator __first, iterator __last)
00708       { _M_t.erase(__first, __last); }
00709 #endif
00710 
00711       /**
00712        *  Erases all elements in a %multiset.  Note that this function only
00713        *  erases the elements, and that if the elements themselves are pointers,
00714        *  the pointed-to memory is not touched in any way.  Managing the pointer
00715        *  is the user's responsibility.
00716        */
00717       void
00718       clear() _GLIBCXX_NOEXCEPT
00719       { _M_t.clear(); }
00720 
00721       // multiset operations:
00722 
00723       //@{
00724       /**
00725        *  @brief Finds the number of elements with given key.
00726        *  @param  __x  Key of elements to be located.
00727        *  @return Number of elements with specified key.
00728        */
00729       size_type
00730       count(const key_type& __x) const
00731       { return _M_t.count(__x); }
00732 
00733 #if __cplusplus > 201103L
00734       template<typename _Kt>
00735         auto
00736         count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
00737         { return _M_t._M_count_tr(__x); }
00738 #endif
00739       //@}
00740 
00741 #if __cplusplus > 201703L
00742       //@{
00743       /**
00744        *  @brief  Finds whether an element with the given key exists.
00745        *  @param  __x  Key of elements to be located.
00746        *  @return  True if there is any element with the specified key.
00747        */
00748       bool
00749       contains(const key_type& __x) const
00750       { return _M_t.find(__x) != _M_t.end(); }
00751 
00752       template<typename _Kt>
00753         auto
00754         contains(const _Kt& __x) const
00755         -> decltype(_M_t._M_find_tr(__x), void(), true)
00756         { return _M_t._M_find_tr(__x) != _M_t.end(); }
00757       //@}
00758 #endif
00759 
00760       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00761       // 214.  set::find() missing const overload
00762       //@{
00763       /**
00764        *  @brief Tries to locate an element in a %set.
00765        *  @param  __x  Element to be located.
00766        *  @return  Iterator pointing to sought-after element, or end() if not
00767        *           found.
00768        *
00769        *  This function takes a key and tries to locate the element with which
00770        *  the key matches.  If successful the function returns an iterator
00771        *  pointing to the sought after element.  If unsuccessful it returns the
00772        *  past-the-end ( @c end() ) iterator.
00773        */
00774       iterator
00775       find(const key_type& __x)
00776       { return _M_t.find(__x); }
00777 
00778       const_iterator
00779       find(const key_type& __x) const
00780       { return _M_t.find(__x); }
00781 
00782 #if __cplusplus > 201103L
00783       template<typename _Kt>
00784         auto
00785         find(const _Kt& __x)
00786         -> decltype(iterator{_M_t._M_find_tr(__x)})
00787         { return iterator{_M_t._M_find_tr(__x)}; }
00788 
00789       template<typename _Kt>
00790         auto
00791         find(const _Kt& __x) const
00792         -> decltype(const_iterator{_M_t._M_find_tr(__x)})
00793         { return const_iterator{_M_t._M_find_tr(__x)}; }
00794 #endif
00795       //@}
00796 
00797       //@{
00798       /**
00799        *  @brief Finds the beginning of a subsequence matching given key.
00800        *  @param  __x  Key to be located.
00801        *  @return  Iterator pointing to first element equal to or greater
00802        *           than key, or end().
00803        *
00804        *  This function returns the first element of a subsequence of elements
00805        *  that matches the given key.  If unsuccessful it returns an iterator
00806        *  pointing to the first element that has a greater value than given key
00807        *  or end() if no such element exists.
00808        */
00809       iterator
00810       lower_bound(const key_type& __x)
00811       { return _M_t.lower_bound(__x); }
00812 
00813       const_iterator
00814       lower_bound(const key_type& __x) const
00815       { return _M_t.lower_bound(__x); }
00816 
00817 #if __cplusplus > 201103L
00818       template<typename _Kt>
00819         auto
00820         lower_bound(const _Kt& __x)
00821         -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
00822         { return iterator(_M_t._M_lower_bound_tr(__x)); }
00823 
00824       template<typename _Kt>
00825         auto
00826         lower_bound(const _Kt& __x) const
00827         -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
00828         { return iterator(_M_t._M_lower_bound_tr(__x)); }
00829 #endif
00830       //@}
00831 
00832       //@{
00833       /**
00834        *  @brief Finds the end of a subsequence matching given key.
00835        *  @param  __x  Key to be located.
00836        *  @return Iterator pointing to the first element
00837        *          greater than key, or end().
00838        */
00839       iterator
00840       upper_bound(const key_type& __x)
00841       { return _M_t.upper_bound(__x); }
00842 
00843       const_iterator
00844       upper_bound(const key_type& __x) const
00845       { return _M_t.upper_bound(__x); }
00846 
00847 #if __cplusplus > 201103L
00848       template<typename _Kt>
00849         auto
00850         upper_bound(const _Kt& __x)
00851         -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
00852         { return iterator(_M_t._M_upper_bound_tr(__x)); }
00853 
00854       template<typename _Kt>
00855         auto
00856         upper_bound(const _Kt& __x) const
00857         -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
00858         { return iterator(_M_t._M_upper_bound_tr(__x)); }
00859 #endif
00860       //@}
00861 
00862       //@{
00863       /**
00864        *  @brief Finds a subsequence matching given key.
00865        *  @param  __x  Key to be located.
00866        *  @return  Pair of iterators that possibly points to the subsequence
00867        *           matching given key.
00868        *
00869        *  This function is equivalent to
00870        *  @code
00871        *    std::make_pair(c.lower_bound(val),
00872        *                   c.upper_bound(val))
00873        *  @endcode
00874        *  (but is faster than making the calls separately).
00875        *
00876        *  This function probably only makes sense for multisets.
00877        */
00878       std::pair<iterator, iterator>
00879       equal_range(const key_type& __x)
00880       { return _M_t.equal_range(__x); }
00881 
00882       std::pair<const_iterator, const_iterator>
00883       equal_range(const key_type& __x) const
00884       { return _M_t.equal_range(__x); }
00885 
00886 #if __cplusplus > 201103L
00887       template<typename _Kt>
00888         auto
00889         equal_range(const _Kt& __x)
00890         -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
00891         { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
00892 
00893       template<typename _Kt>
00894         auto
00895         equal_range(const _Kt& __x) const
00896         -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
00897         { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
00898 #endif
00899       //@}
00900 
00901       template<typename _K1, typename _C1, typename _A1>
00902         friend bool
00903         operator==(const multiset<_K1, _C1, _A1>&,
00904                    const multiset<_K1, _C1, _A1>&);
00905 
00906       template<typename _K1, typename _C1, typename _A1>
00907         friend bool
00908         operator< (const multiset<_K1, _C1, _A1>&,
00909                    const multiset<_K1, _C1, _A1>&);
00910     };
00911 
00912 #if __cpp_deduction_guides >= 201606
00913 
00914   template<typename _InputIterator,
00915            typename _Compare =
00916              less<typename iterator_traits<_InputIterator>::value_type>,
00917            typename _Allocator =
00918              allocator<typename iterator_traits<_InputIterator>::value_type>,
00919            typename = _RequireInputIter<_InputIterator>,
00920            typename = _RequireNotAllocator<_Compare>,
00921            typename = _RequireAllocator<_Allocator>>
00922     multiset(_InputIterator, _InputIterator,
00923              _Compare = _Compare(), _Allocator = _Allocator())
00924     -> multiset<typename iterator_traits<_InputIterator>::value_type,
00925                 _Compare, _Allocator>;
00926 
00927   template<typename _Key,
00928            typename _Compare = less<_Key>,
00929            typename _Allocator = allocator<_Key>,
00930            typename = _RequireNotAllocator<_Compare>,
00931            typename = _RequireAllocator<_Allocator>>
00932     multiset(initializer_list<_Key>,
00933              _Compare = _Compare(), _Allocator = _Allocator())
00934     -> multiset<_Key, _Compare, _Allocator>;
00935 
00936   template<typename _InputIterator, typename _Allocator,
00937            typename = _RequireInputIter<_InputIterator>,
00938            typename = _RequireAllocator<_Allocator>>
00939     multiset(_InputIterator, _InputIterator, _Allocator)
00940     -> multiset<typename iterator_traits<_InputIterator>::value_type,
00941                 less<typename iterator_traits<_InputIterator>::value_type>,
00942                 _Allocator>;
00943 
00944   template<typename _Key, typename _Allocator,
00945            typename = _RequireAllocator<_Allocator>>
00946     multiset(initializer_list<_Key>, _Allocator)
00947     -> multiset<_Key, less<_Key>, _Allocator>;
00948 
00949 #endif
00950 
00951   /**
00952    *  @brief  Multiset equality comparison.
00953    *  @param  __x  A %multiset.
00954    *  @param  __y  A %multiset of the same type as @a __x.
00955    *  @return  True iff the size and elements of the multisets are equal.
00956    *
00957    *  This is an equivalence relation.  It is linear in the size of the
00958    *  multisets.
00959    *  Multisets are considered equivalent if their sizes are equal, and if
00960    *  corresponding elements compare equal.
00961   */
00962   template<typename _Key, typename _Compare, typename _Alloc>
00963     inline bool
00964     operator==(const multiset<_Key, _Compare, _Alloc>& __x,
00965                const multiset<_Key, _Compare, _Alloc>& __y)
00966     { return __x._M_t == __y._M_t; }
00967 
00968   /**
00969    *  @brief  Multiset ordering relation.
00970    *  @param  __x  A %multiset.
00971    *  @param  __y  A %multiset of the same type as @a __x.
00972    *  @return  True iff @a __x is lexicographically less than @a __y.
00973    *
00974    *  This is a total ordering relation.  It is linear in the size of the
00975    *  sets.  The elements must be comparable with @c <.
00976    *
00977    *  See std::lexicographical_compare() for how the determination is made.
00978   */
00979   template<typename _Key, typename _Compare, typename _Alloc>
00980     inline bool
00981     operator<(const multiset<_Key, _Compare, _Alloc>& __x,
00982               const multiset<_Key, _Compare, _Alloc>& __y)
00983     { return __x._M_t < __y._M_t; }
00984 
00985   ///  Returns !(x == y).
00986   template<typename _Key, typename _Compare, typename _Alloc>
00987     inline bool
00988     operator!=(const multiset<_Key, _Compare, _Alloc>& __x,
00989                const multiset<_Key, _Compare, _Alloc>& __y)
00990     { return !(__x == __y); }
00991 
00992   ///  Returns y < x.
00993   template<typename _Key, typename _Compare, typename _Alloc>
00994     inline bool
00995     operator>(const multiset<_Key,_Compare,_Alloc>& __x,
00996               const multiset<_Key,_Compare,_Alloc>& __y)
00997     { return __y < __x; }
00998 
00999   ///  Returns !(y < x)
01000   template<typename _Key, typename _Compare, typename _Alloc>
01001     inline bool
01002     operator<=(const multiset<_Key, _Compare, _Alloc>& __x,
01003                const multiset<_Key, _Compare, _Alloc>& __y)
01004     { return !(__y < __x); }
01005 
01006   ///  Returns !(x < y)
01007   template<typename _Key, typename _Compare, typename _Alloc>
01008     inline bool
01009     operator>=(const multiset<_Key, _Compare, _Alloc>& __x,
01010                const multiset<_Key, _Compare, _Alloc>& __y)
01011     { return !(__x < __y); }
01012 
01013   /// See std::multiset::swap().
01014   template<typename _Key, typename _Compare, typename _Alloc>
01015     inline void
01016     swap(multiset<_Key, _Compare, _Alloc>& __x,
01017          multiset<_Key, _Compare, _Alloc>& __y)
01018     _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
01019     { __x.swap(__y); }
01020 
01021 _GLIBCXX_END_NAMESPACE_CONTAINER
01022 
01023 #if __cplusplus > 201402L
01024   // Allow std::multiset access to internals of compatible sets.
01025   template<typename _Val, typename _Cmp1, typename _Alloc, typename _Cmp2>
01026     struct
01027     _Rb_tree_merge_helper<_GLIBCXX_STD_C::multiset<_Val, _Cmp1, _Alloc>,
01028                           _Cmp2>
01029     {
01030     private:
01031       friend class _GLIBCXX_STD_C::multiset<_Val, _Cmp1, _Alloc>;
01032 
01033       static auto&
01034       _S_get_tree(_GLIBCXX_STD_C::set<_Val, _Cmp2, _Alloc>& __set)
01035       { return __set._M_t; }
01036 
01037       static auto&
01038       _S_get_tree(_GLIBCXX_STD_C::multiset<_Val, _Cmp2, _Alloc>& __set)
01039       { return __set._M_t; }
01040     };
01041 
01042 #endif // C++17
01043 
01044 _GLIBCXX_END_NAMESPACE_VERSION
01045 } // namespace std
01046 
01047 #endif /* _STL_MULTISET_H */