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// Multimap implementation -*- C++ -*-
// Copyright (C) 2001-2021 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file bits/stl_multimap.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{map}
*/
#ifndef _STL_MULTIMAP_H
#define _STL_MULTIMAP_H 1
#include <bits/concept_check.h>
#if __cplusplus >= 201103L
#include <initializer_list>
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
class map;
/**
* @brief A standard container made up of (key,value) pairs, which can be
* retrieved based on a key, in logarithmic time.
*
* @ingroup associative_containers
*
* @tparam _Key Type of key objects.
* @tparam _Tp Type of mapped objects.
* @tparam _Compare Comparison function object type, defaults to less<_Key>.
* @tparam _Alloc Allocator type, defaults to
* allocator<pair<const _Key, _Tp>.
*
* Meets the requirements of a <a href="tables.html#65">container</a>, a
* <a href="tables.html#66">reversible container</a>, and an
* <a href="tables.html#69">associative container</a> (using equivalent
* keys). For a @c multimap<Key,T> the key_type is Key, the mapped_type
* is T, and the value_type is std::pair<const Key,T>.
*
* Multimaps support bidirectional iterators.
*
* The private tree data is declared exactly the same way for map and
* multimap; the distinction is made entirely in how the tree functions are
* called (*_unique versus *_equal, same as the standard).
*/
template <typename _Key, typename _Tp,
typename _Compare = std::less<_Key>,
typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
class multimap
{
public:
typedef _Key key_type;
typedef _Tp mapped_type;
typedef std::pair<const _Key, _Tp> value_type;
typedef _Compare key_compare;
typedef _Alloc allocator_type;
private:
#ifdef _GLIBCXX_CONCEPT_CHECKS
// concept requirements
typedef typename _Alloc::value_type _Alloc_value_type;
# if __cplusplus < 201103L
__glibcxx_class_requires(_Tp, _SGIAssignableConcept)
# endif
__glibcxx_class_requires4(_Compare, bool, _Key, _Key,
_BinaryFunctionConcept)
__glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
#endif
#if __cplusplus >= 201103L
#if __cplusplus > 201703L || defined __STRICT_ANSI__
static_assert(is_same<typename _Alloc::value_type, value_type>::value,
"std::multimap must have the same value_type as its allocator");
#endif
#endif
public:
class value_compare
: public std::binary_function<value_type, value_type, bool>
{
friend class multimap<_Key, _Tp, _Compare, _Alloc>;
protected:
_Compare comp;
value_compare(_Compare __c)
: comp(__c) { }
public:
bool operator()(const value_type& __x, const value_type& __y) const
{ return comp(__x.first, __y.first); }
};
private:
/// This turns a red-black tree into a [multi]map.
typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
rebind<value_type>::other _Pair_alloc_type;
typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
key_compare, _Pair_alloc_type> _Rep_type;
/// The actual tree structure.
_Rep_type _M_t;
typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits;
public:
// many of these are specified differently in ISO, but the following are
// "functionally equivalent"
typedef typename _Alloc_traits::pointer pointer;
typedef typename _Alloc_traits::const_pointer const_pointer;
typedef typename _Alloc_traits::reference reference;
typedef typename _Alloc_traits::const_reference const_reference;
typedef typename _Rep_type::iterator iterator;
typedef typename _Rep_type::const_iterator const_iterator;
typedef typename _Rep_type::size_type size_type;
typedef typename _Rep_type::difference_type difference_type;
typedef typename _Rep_type::reverse_iterator reverse_iterator;
typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
#if __cplusplus > 201402L
using node_type = typename _Rep_type::node_type;
#endif
// [23.3.2] construct/copy/destroy
// (get_allocator() is also listed in this section)
/**
* @brief Default constructor creates no elements.
*/
#if __cplusplus < 201103L
multimap() : _M_t() { }
#else
multimap() = default;
#endif
/**
* @brief Creates a %multimap with no elements.
* @param __comp A comparison object.
* @param __a An allocator object.
*/
explicit
multimap(const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, _Pair_alloc_type(__a)) { }
/**
* @brief %Multimap copy constructor.
*
* Whether the allocator is copied depends on the allocator traits.
*/
#if __cplusplus < 201103L
multimap(const multimap& __x)
: _M_t(__x._M_t) { }
#else
multimap(const multimap&) = default;
/**
* @brief %Multimap move constructor.
*
* The newly-created %multimap contains the exact contents of the
* moved instance. The moved instance is a valid, but unspecified
* %multimap.
*/
multimap(multimap&&) = default;
/**
* @brief Builds a %multimap from an initializer_list.
* @param __l An initializer_list.
* @param __comp A comparison functor.
* @param __a An allocator object.
*
* Create a %multimap consisting of copies of the elements from
* the initializer_list. This is linear in N if the list is already
* sorted, and NlogN otherwise (where N is @a __l.size()).
*/
multimap(initializer_list<value_type> __l,
const _Compare& __comp = _Compare(),
const allocator_type& __a = allocator_type())
: _M_t(__comp, _Pair_alloc_type(__a))
{ _M_t._M_insert_range_equal(__l.begin(), __l.end()); }
/// Allocator-extended default constructor.
explicit
multimap(const allocator_type& __a)
: _M_t(_Pair_alloc_type(__a)) { }
/// Allocator-extended copy constructor.
multimap(const multimap& __m, const allocator_type& __a)
: _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
/// Allocator-extended move constructor.
multimap(multimap&& __m, const allocator_type& __a)
noexcept(is_nothrow_copy_constructible<_Compare>::value
&& _Alloc_traits::_S_always_equal())
: _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
/// Allocator-extended initialier-list constructor.
multimap(initializer_list<value_type> __l, const allocator_type& __a)
: _M_t(_Pair_alloc_type(__a))
{ _M_t._M_insert_range_equal(__l.begin(), __l.end()); }
/// Allocator-extended range constructor.
template<typename _InputIterator>
multimap(_InputIterator __first, _InputIterator __last,
const allocator_type& __a)
: _M_t(_Pair_alloc_type(__a))
{ _M_t._M_insert_range_equal(__first, __last); }
#endif
/**
* @brief Builds a %multimap from a range.
* @param __first An input iterator.
* @param __last An input iterator.
*
* Create a %multimap consisting of copies of the elements from
* [__first,__last). This is linear in N if the range is already sorted,
* and NlogN otherwise (where N is distance(__first,__last)).
*/
template<typename _InputIterator>
multimap(_InputIterator __first, _InputIterator __last)
: _M_t()
{ _M_t._M_insert_range_equal(__first, __last); }
/**
* @brief Builds a %multimap from a range.
* @param __first An input iterator.
* @param __last An input iterator.
* @param __comp A comparison functor.
* @param __a An allocator object.
*
* Create a %multimap consisting of copies of the elements from
* [__first,__last). This is linear in N if the range is already sorted,
* and NlogN otherwise (where N is distance(__first,__last)).
*/
template<typename _InputIterator>
multimap(_InputIterator __first, _InputIterator __last,
const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, _Pair_alloc_type(__a))
{ _M_t._M_insert_range_equal(__first, __last); }
#if __cplusplus >= 201103L
/**
* The dtor only erases the elements, and note that if the elements
* themselves are pointers, the pointed-to memory is not touched in any
* way. Managing the pointer is the user's responsibility.
*/
~multimap() = default;
#endif
/**
* @brief %Multimap assignment operator.
*
* Whether the allocator is copied depends on the allocator traits.
*/
#if __cplusplus < 201103L
multimap&
operator=(const multimap& __x)
{
_M_t = __x._M_t;
return *this;
}
#else
multimap&
operator=(const multimap&) = default;
/// Move assignment operator.
multimap&
operator=(multimap&&) = default;
/**
* @brief %Multimap list assignment operator.
* @param __l An initializer_list.
*
* This function fills a %multimap with copies of the elements
* in the initializer list @a __l.
*
* Note that the assignment completely changes the %multimap and
* that the resulting %multimap's size is the same as the number
* of elements assigned.
*/
multimap&
operator=(initializer_list<value_type> __l)
{
_M_t._M_assign_equal(__l.begin(), __l.end());
return *this;
}
#endif
/// Get a copy of the memory allocation object.
allocator_type
get_allocator() const _GLIBCXX_NOEXCEPT
{ return allocator_type(_M_t.get_allocator()); }
// iterators
/**
* Returns a read/write iterator that points to the first pair in the
* %multimap. Iteration is done in ascending order according to the
* keys.
*/
iterator
begin() _GLIBCXX_NOEXCEPT
{ return _M_t.begin(); }
/**
* Returns a read-only (constant) iterator that points to the first pair
* in the %multimap. Iteration is done in ascending order according to
* the keys.
*/
const_iterator
begin() const _GLIBCXX_NOEXCEPT
{ return _M_t.begin(); }
/**
* Returns a read/write iterator that points one past the last pair in
* the %multimap. Iteration is done in ascending order according to the
* keys.
*/
iterator
end() _GLIBCXX_NOEXCEPT
{ return _M_t.end(); }
/**
* Returns a read-only (constant) iterator that points one past the last
* pair in the %multimap. Iteration is done in ascending order according
* to the keys.
*/
const_iterator
end() const _GLIBCXX_NOEXCEPT
{ return _M_t.end(); }
/**
* Returns a read/write reverse iterator that points to the last pair in
* the %multimap. Iteration is done in descending order according to the
* keys.
*/
reverse_iterator
rbegin() _GLIBCXX_NOEXCEPT
{ return _M_t.rbegin(); }
/**
* Returns a read-only (constant) reverse iterator that points to the
* last pair in the %multimap. Iteration is done in descending order
* according to the keys.
*/
const_reverse_iterator
rbegin() const _GLIBCXX_NOEXCEPT
{ return _M_t.rbegin(); }
/**
* Returns a read/write reverse iterator that points to one before the
* first pair in the %multimap. Iteration is done in descending order
* according to the keys.
*/
reverse_iterator
rend() _GLIBCXX_NOEXCEPT
{ return _M_t.rend(); }
/**
* Returns a read-only (constant) reverse iterator that points to one
* before the first pair in the %multimap. Iteration is done in
* descending order according to the keys.
*/
const_reverse_iterator
rend() const _GLIBCXX_NOEXCEPT
{ return _M_t.rend(); }
#if __cplusplus >= 201103L
/**
* Returns a read-only (constant) iterator that points to the first pair
* in the %multimap. Iteration is done in ascending order according to
* the keys.
*/
const_iterator
cbegin() const noexcept
{ return _M_t.begin(); }
/**
* Returns a read-only (constant) iterator that points one past the last
* pair in the %multimap. Iteration is done in ascending order according
* to the keys.
*/
const_iterator
cend() const noexcept
{ return _M_t.end(); }
/**
* Returns a read-only (constant) reverse iterator that points to the
* last pair in the %multimap. Iteration is done in descending order
* according to the keys.
*/
const_reverse_iterator
crbegin() const noexcept
{ return _M_t.rbegin(); }
/**
* Returns a read-only (constant) reverse iterator that points to one
* before the first pair in the %multimap. Iteration is done in
* descending order according to the keys.
*/
const_reverse_iterator
crend() const noexcept
{ return _M_t.rend(); }
#endif
// capacity
/** Returns true if the %multimap is empty. */
_GLIBCXX_NODISCARD bool
empty() const _GLIBCXX_NOEXCEPT
{ return _M_t.empty(); }
/** Returns the size of the %multimap. */
size_type
size() const _GLIBCXX_NOEXCEPT
{ return _M_t.size(); }
/** Returns the maximum size of the %multimap. */
size_type
max_size() const _GLIBCXX_NOEXCEPT
{ return _M_t.max_size(); }
// modifiers
#if __cplusplus >= 201103L
/**
* @brief Build and insert a std::pair into the %multimap.
*
* @param __args Arguments used to generate a new pair instance (see
* std::piecewise_contruct for passing arguments to each
* part of the pair constructor).
*
* @return An iterator that points to the inserted (key,value) pair.
*
* This function builds and inserts a (key, value) %pair into the
* %multimap.
* Contrary to a std::map the %multimap does not rely on unique keys and
* thus multiple pairs with the same key can be inserted.
*
* Insertion requires logarithmic time.
*/
template<typename... _Args>
iterator
emplace(_Args&&... __args)
{ return _M_t._M_emplace_equal(std::forward<_Args>(__args)...); }
/**
* @brief Builds and inserts a std::pair into the %multimap.
*
* @param __pos An iterator that serves as a hint as to where the pair
* should be inserted.
* @param __args Arguments used to generate a new pair instance (see
* std::piecewise_contruct for passing arguments to each
* part of the pair constructor).
* @return An iterator that points to the inserted (key,value) pair.
*
* This function inserts a (key, value) pair into the %multimap.
* Contrary to a std::map the %multimap does not rely on unique keys and
* thus multiple pairs with the same key can be inserted.
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* For more on @a hinting, see:
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
*
* Insertion requires logarithmic time (if the hint is not taken).
*/
template<typename... _Args>
iterator
emplace_hint(const_iterator __pos, _Args&&... __args)
{
return _M_t._M_emplace_hint_equal(__pos,
std::forward<_Args>(__args)...);
}
#endif
/**
* @brief Inserts a std::pair into the %multimap.
* @param __x Pair to be inserted (see std::make_pair for easy creation
* of pairs).
* @return An iterator that points to the inserted (key,value) pair.
*
* This function inserts a (key, value) pair into the %multimap.
* Contrary to a std::map the %multimap does not rely on unique keys and
* thus multiple pairs with the same key can be inserted.
*
* Insertion requires logarithmic time.
* @{
*/
iterator
insert(const value_type& __x)
{ return _M_t._M_insert_equal(__x); }
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2354. Unnecessary copying when inserting into maps with braced-init
iterator
insert(value_type&& __x)
{ return _M_t._M_insert_equal(std::move(__x)); }
template<typename _Pair>
__enable_if_t<is_constructible<value_type, _Pair>::value, iterator>
insert(_Pair&& __x)
{ return _M_t._M_emplace_equal(std::forward<_Pair>(__x)); }
#endif
/// @}
/**
* @brief Inserts a std::pair into the %multimap.
* @param __position An iterator that serves as a hint as to where the
* pair should be inserted.
* @param __x Pair to be inserted (see std::make_pair for easy creation
* of pairs).
* @return An iterator that points to the inserted (key,value) pair.
*
* This function inserts a (key, value) pair into the %multimap.
* Contrary to a std::map the %multimap does not rely on unique keys and
* thus multiple pairs with the same key can be inserted.
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* For more on @a hinting, see:
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
*
* Insertion requires logarithmic time (if the hint is not taken).
* @{
*/
iterator
#if __cplusplus >= 201103L
insert(const_iterator __position, const value_type& __x)
#else
insert(iterator __position, const value_type& __x)
#endif
{ return _M_t._M_insert_equal_(__position, __x); }
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2354. Unnecessary copying when inserting into maps with braced-init
iterator
insert(const_iterator __position, value_type&& __x)
{ return _M_t._M_insert_equal_(__position, std::move(__x)); }
template<typename _Pair>
__enable_if_t<is_constructible<value_type, _Pair&&>::value, iterator>
insert(const_iterator __position, _Pair&& __x)
{
return _M_t._M_emplace_hint_equal(__position,
std::forward<_Pair>(__x));
}
#endif
/// @}
/**
* @brief A template function that attempts to insert a range
* of elements.
* @param __first Iterator pointing to the start of the range to be
* inserted.
* @param __last Iterator pointing to the end of the range.
*
* Complexity similar to that of the range constructor.
*/
template<typename _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last)
{ _M_t._M_insert_range_equal(__first, __last); }
#if __cplusplus >= 201103L
/**
* @brief Attempts to insert a list of std::pairs into the %multimap.
* @param __l A std::initializer_list<value_type> of pairs to be
* inserted.
*
* Complexity similar to that of the range constructor.
*/
void
insert(initializer_list<value_type> __l)
{ this->insert(__l.begin(), __l.end()); }
#endif
#if __cplusplus > 201402L
/// Extract a node.
node_type
extract(const_iterator __pos)
{
__glibcxx_assert(__pos != end());
return _M_t.extract(__pos);
}
/// Extract a node.
node_type
extract(const key_type& __x)
{ return _M_t.extract(__x); }
/// Re-insert an extracted node.
iterator
insert(node_type&& __nh)
{ return _M_t._M_reinsert_node_equal(std::move(__nh)); }
/// Re-insert an extracted node.
iterator
insert(const_iterator __hint, node_type&& __nh)
{ return _M_t._M_reinsert_node_hint_equal(__hint, std::move(__nh)); }
template<typename, typename>
friend struct std::_Rb_tree_merge_helper;
template<typename _Cmp2>
void
merge(multimap<_Key, _Tp, _Cmp2, _Alloc>& __source)
{
using _Merge_helper = _Rb_tree_merge_helper<multimap, _Cmp2>;
_M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
}
template<typename _Cmp2>
void
merge(multimap<_Key, _Tp, _Cmp2, _Alloc>&& __source)
{ merge(__source); }
template<typename _Cmp2>
void
merge(map<_Key, _Tp, _Cmp2, _Alloc>& __source)
{
using _Merge_helper = _Rb_tree_merge_helper<multimap, _Cmp2>;
_M_t._M_merge_equal(_Merge_helper::_S_get_tree(__source));
}
template<typename _Cmp2>
void
merge(map<_Key, _Tp, _Cmp2, _Alloc>&& __source)
{ merge(__source); }
#endif // C++17
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 130. Associative erase should return an iterator.
/**
* @brief Erases an element from a %multimap.
* @param __position An iterator pointing to the element to be erased.
* @return An iterator pointing to the element immediately following
* @a position prior to the element being erased. If no such
* element exists, end() is returned.
*
* This function erases an element, pointed to by the given iterator,
* from a %multimap. Note that this function only erases the element,
* and that if the element is itself a pointer, the pointed-to memory is
* not touched in any way. Managing the pointer is the user's
* responsibility.
*
* @{
*/
iterator
erase(const_iterator __position)
{ return _M_t.erase(__position); }
// LWG 2059.
_GLIBCXX_ABI_TAG_CXX11
iterator
erase(iterator __position)
{ return _M_t.erase(__position); }
/// @}
#else
/**
* @brief Erases an element from a %multimap.
* @param __position An iterator pointing to the element to be erased.
*
* This function erases an element, pointed to by the given iterator,
* from a %multimap. Note that this function only erases the element,
* and that if the element is itself a pointer, the pointed-to memory is
* not touched in any way. Managing the pointer is the user's
* responsibility.
*/
void
erase(iterator __position)
{ _M_t.erase(__position); }
#endif
/**
* @brief Erases elements according to the provided key.
* @param __x Key of element to be erased.
* @return The number of elements erased.
*
* This function erases all elements located by the given key from a
* %multimap.
* Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibility.
*/
size_type
erase(const key_type& __x)
{ return _M_t.erase(__x); }
#if __cplusplus >= 201103L
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 130. Associative erase should return an iterator.
/**
* @brief Erases a [first,last) range of elements from a %multimap.
* @param __first Iterator pointing to the start of the range to be
* erased.
* @param __last Iterator pointing to the end of the range to be
* erased .
* @return The iterator @a __last.
*
* This function erases a sequence of elements from a %multimap.
* Note that this function only erases the elements, and that if
* the elements themselves are pointers, the pointed-to memory is not
* touched in any way. Managing the pointer is the user's
* responsibility.
*/
iterator
erase(const_iterator __first, const_iterator __last)
{ return _M_t.erase(__first, __last); }
#else
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 130. Associative erase should return an iterator.
/**
* @brief Erases a [first,last) range of elements from a %multimap.
* @param __first Iterator pointing to the start of the range to be
* erased.
* @param __last Iterator pointing to the end of the range to
* be erased.
*
* This function erases a sequence of elements from a %multimap.
* Note that this function only erases the elements, and that if
* the elements themselves are pointers, the pointed-to memory is not
* touched in any way. Managing the pointer is the user's
* responsibility.
*/
void
erase(iterator __first, iterator __last)
{ _M_t.erase(__first, __last); }
#endif
/**
* @brief Swaps data with another %multimap.
* @param __x A %multimap of the same element and allocator types.
*
* This exchanges the elements between two multimaps in constant time.
* (It is only swapping a pointer, an integer, and an instance of
* the @c Compare type (which itself is often stateless and empty), so it
* should be quite fast.)
* Note that the global std::swap() function is specialized such that
* std::swap(m1,m2) will feed to this function.
*
* Whether the allocators are swapped depends on the allocator traits.
*/
void
swap(multimap& __x)
_GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
{ _M_t.swap(__x._M_t); }
/**
* Erases all elements in a %multimap. Note that this function only
* erases the elements, and that if the elements themselves are pointers,
* the pointed-to memory is not touched in any way. Managing the pointer
* is the user's responsibility.
*/
void
clear() _GLIBCXX_NOEXCEPT
{ _M_t.clear(); }
// observers
/**
* Returns the key comparison object out of which the %multimap
* was constructed.
*/
key_compare
key_comp() const
{ return _M_t.key_comp(); }
/**
* Returns a value comparison object, built from the key comparison
* object out of which the %multimap was constructed.
*/
value_compare
value_comp() const
{ return value_compare(_M_t.key_comp()); }
// multimap operations
///@{
/**
* @brief Tries to locate an element in a %multimap.
* @param __x Key of (key, value) pair to be located.
* @return Iterator pointing to sought-after element,
* or end() if not found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns an iterator
* pointing to the sought after %pair. If unsuccessful it returns the
* past-the-end ( @c end() ) iterator.
*/
iterator
find(const key_type& __x)
{ return _M_t.find(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
{ return _M_t._M_find_tr(__x); }
#endif
///@}
///@{
/**
* @brief Tries to locate an element in a %multimap.
* @param __x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to sought-after
* element, or end() if not found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns a constant
* iterator pointing to the sought after %pair. If unsuccessful it
* returns the past-the-end ( @c end() ) iterator.
*/
const_iterator
find(const key_type& __x) const
{ return _M_t.find(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
{ return _M_t._M_find_tr(__x); }
#endif
///@}
///@{
/**
* @brief Finds the number of elements with given key.
* @param __x Key of (key, value) pairs to be located.
* @return Number of elements with specified key.
*/
size_type
count(const key_type& __x) const
{ return _M_t.count(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
{ return _M_t._M_count_tr(__x); }
#endif
///@}
#if __cplusplus > 201703L
///@{
/**
* @brief Finds whether an element with the given key exists.
* @param __x Key of (key, value) pairs to be located.
* @return True if there is any element with the specified key.
*/
bool
contains(const key_type& __x) const
{ return _M_t.find(__x) != _M_t.end(); }
template<typename _Kt>
auto
contains(const _Kt& __x) const
-> decltype(_M_t._M_find_tr(__x), void(), true)
{ return _M_t._M_find_tr(__x) != _M_t.end(); }
///@}
#endif
///@{
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param __x Key of (key, value) pair to be located.
* @return Iterator pointing to first element equal to or greater
* than key, or end().
*
* This function returns the first element of a subsequence of elements
* that matches the given key. If unsuccessful it returns an iterator
* pointing to the first element that has a greater value than given key
* or end() if no such element exists.
*/
iterator
lower_bound(const key_type& __x)
{ return _M_t.lower_bound(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
lower_bound(const _Kt& __x)
-> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
{ return iterator(_M_t._M_lower_bound_tr(__x)); }
#endif
///@}
///@{
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param __x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to first element
* equal to or greater than key, or end().
*
* This function returns the first element of a subsequence of
* elements that matches the given key. If unsuccessful the
* iterator will point to the next greatest element or, if no
* such greater element exists, to end().
*/
const_iterator
lower_bound(const key_type& __x) const
{ return _M_t.lower_bound(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
lower_bound(const _Kt& __x) const
-> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
{ return const_iterator(_M_t._M_lower_bound_tr(__x)); }
#endif
///@}
///@{
/**
* @brief Finds the end of a subsequence matching given key.
* @param __x Key of (key, value) pair to be located.
* @return Iterator pointing to the first element
* greater than key, or end().
*/
iterator
upper_bound(const key_type& __x)
{ return _M_t.upper_bound(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
upper_bound(const _Kt& __x)
-> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
{ return iterator(_M_t._M_upper_bound_tr(__x)); }
#endif
///@}
///@{
/**
* @brief Finds the end of a subsequence matching given key.
* @param __x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to first iterator
* greater than key, or end().
*/
const_iterator
upper_bound(const key_type& __x) const
{ return _M_t.upper_bound(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
upper_bound(const _Kt& __x) const
-> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
{ return const_iterator(_M_t._M_upper_bound_tr(__x)); }
#endif
///@}
///@{
/**
* @brief Finds a subsequence matching given key.
* @param __x Key of (key, value) pairs to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*
* This function is equivalent to
* @code
* std::make_pair(c.lower_bound(val),
* c.upper_bound(val))
* @endcode
* (but is faster than making the calls separately).
*/
std::pair<iterator, iterator>
equal_range(const key_type& __x)
{ return _M_t.equal_range(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
equal_range(const _Kt& __x)
-> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
{ return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
#endif
///@}
///@{
/**
* @brief Finds a subsequence matching given key.
* @param __x Key of (key, value) pairs to be located.
* @return Pair of read-only (constant) iterators that possibly points
* to the subsequence matching given key.
*
* This function is equivalent to
* @code
* std::make_pair(c.lower_bound(val),
* c.upper_bound(val))
* @endcode
* (but is faster than making the calls separately).
*/
std::pair<const_iterator, const_iterator>
equal_range(const key_type& __x) const
{ return _M_t.equal_range(__x); }
#if __cplusplus > 201103L
template<typename _Kt>
auto
equal_range(const _Kt& __x) const
-> decltype(pair<const_iterator, const_iterator>(
_M_t._M_equal_range_tr(__x)))
{
return pair<const_iterator, const_iterator>(
_M_t._M_equal_range_tr(__x));
}
#endif
///@}
template<typename _K1, typename _T1, typename _C1, typename _A1>
friend bool
operator==(const multimap<_K1, _T1, _C1, _A1>&,
const multimap<_K1, _T1, _C1, _A1>&);
#if __cpp_lib_three_way_comparison
template<typename _K1, typename _T1, typename _C1, typename _A1>
friend __detail::__synth3way_t<pair<const _K1, _T1>>
operator<=>(const multimap<_K1, _T1, _C1, _A1>&,
const multimap<_K1, _T1, _C1, _A1>&);
#else
template<typename _K1, typename _T1, typename _C1, typename _A1>
friend bool
operator<(const multimap<_K1, _T1, _C1, _A1>&,
const multimap<_K1, _T1, _C1, _A1>&);
#endif
};
#if __cpp_deduction_guides >= 201606
template<typename _InputIterator,
typename _Compare = less<__iter_key_t<_InputIterator>>,
typename _Allocator = allocator<__iter_to_alloc_t<_InputIterator>>,
typename = _RequireInputIter<_InputIterator>,
typename = _RequireNotAllocator<_Compare>,
typename = _RequireAllocator<_Allocator>>
multimap(_InputIterator, _InputIterator,
_Compare = _Compare(), _Allocator = _Allocator())
-> multimap<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
_Compare, _Allocator>;
template<typename _Key, typename _Tp, typename _Compare = less<_Key>,
typename _Allocator = allocator<pair<const _Key, _Tp>>,
typename = _RequireNotAllocator<_Compare>,
typename = _RequireAllocator<_Allocator>>
multimap(initializer_list<pair<_Key, _Tp>>,
_Compare = _Compare(), _Allocator = _Allocator())
-> multimap<_Key, _Tp, _Compare, _Allocator>;
template<typename _InputIterator, typename _Allocator,
typename = _RequireInputIter<_InputIterator>,
typename = _RequireAllocator<_Allocator>>
multimap(_InputIterator, _InputIterator, _Allocator)
-> multimap<__iter_key_t<_InputIterator>, __iter_val_t<_InputIterator>,
less<__iter_key_t<_InputIterator>>, _Allocator>;
template<typename _Key, typename _Tp, typename _Allocator,
typename = _RequireAllocator<_Allocator>>
multimap(initializer_list<pair<_Key, _Tp>>, _Allocator)
-> multimap<_Key, _Tp, less<_Key>, _Allocator>;
#endif // deduction guides
/**
* @brief Multimap equality comparison.
* @param __x A %multimap.
* @param __y A %multimap of the same type as @a __x.
* @return True iff the size and elements of the maps are equal.
*
* This is an equivalence relation. It is linear in the size of the
* multimaps. Multimaps are considered equivalent if their sizes are equal,
* and if corresponding elements compare equal.
*/
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator==(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return __x._M_t == __y._M_t; }
#if __cpp_lib_three_way_comparison
/**
* @brief Multimap ordering relation.
* @param __x A `multimap`.
* @param __y A `multimap` of the same type as `x`.
* @return A value indicating whether `__x` is less than, equal to,
* greater than, or incomparable with `__y`.
*
* This is a total ordering relation. It is linear in the size of the
* maps. The elements must be comparable with @c <.
*
* See `std::lexicographical_compare_three_way()` for how the determination
* is made. This operator is used to synthesize relational operators like
* `<` and `>=` etc.
*/
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline __detail::__synth3way_t<pair<const _Key, _Tp>>
operator<=>(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return __x._M_t <=> __y._M_t; }
#else
/**
* @brief Multimap ordering relation.
* @param __x A %multimap.
* @param __y A %multimap of the same type as @a __x.
* @return True iff @a x is lexicographically less than @a y.
*
* This is a total ordering relation. It is linear in the size of the
* multimaps. The elements must be comparable with @c <.
*
* See std::lexicographical_compare() for how the determination is made.
*/
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator<(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return __x._M_t < __y._M_t; }
/// Based on operator==
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator!=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return !(__x == __y); }
/// Based on operator<
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator>(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return __y < __x; }
/// Based on operator<
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator<=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return !(__y < __x); }
/// Based on operator<
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator>=(const multimap<_Key, _Tp, _Compare, _Alloc>& __x,
const multimap<_Key, _Tp, _Compare, _Alloc>& __y)
{ return !(__x < __y); }
#endif // three-way comparison
/// See std::multimap::swap().
template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline void
swap(multimap<_Key, _Tp, _Compare, _Alloc>& __x,
multimap<_Key, _Tp, _Compare, _Alloc>& __y)
_GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
{ __x.swap(__y); }
_GLIBCXX_END_NAMESPACE_CONTAINER
#if __cplusplus > 201402L
// Allow std::multimap access to internals of compatible maps.
template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
typename _Cmp2>
struct
_Rb_tree_merge_helper<_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp1, _Alloc>,
_Cmp2>
{
private:
friend class _GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp1, _Alloc>;
static auto&
_S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
{ return __map._M_t; }
static auto&
_S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
{ return __map._M_t; }
};
#endif // C++17
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif /* _STL_MULTIMAP_H */