mirror of git://gcc.gnu.org/git/gcc.git
1794 lines
61 KiB
C++
1794 lines
61 KiB
C++
// unordered_map implementation -*- C++ -*-
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// Copyright (C) 2010-2016 Free Software Foundation, Inc.
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//
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// This file is part of the GNU ISO C++ Library. This library is free
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// software; you can redistribute it and/or modify it under the
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// terms of the GNU General Public License as published by the
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// Free Software Foundation; either version 3, or (at your option)
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// any later version.
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// Under Section 7 of GPL version 3, you are granted additional
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// permissions described in the GCC Runtime Library Exception, version
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// 3.1, as published by the Free Software Foundation.
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// You should have received a copy of the GNU General Public License and
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// a copy of the GCC Runtime Library Exception along with this program;
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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// <http://www.gnu.org/licenses/>.
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/** @file bits/unordered_map.h
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* This is an internal header file, included by other library headers.
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* Do not attempt to use it directly. @headername{unordered_map}
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*/
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#ifndef _UNORDERED_MAP_H
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#define _UNORDERED_MAP_H
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namespace std _GLIBCXX_VISIBILITY(default)
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{
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_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
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/// Base types for unordered_map.
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template<bool _Cache>
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using __umap_traits = __detail::_Hashtable_traits<_Cache, false, true>;
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template<typename _Key,
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typename _Tp,
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typename _Hash = hash<_Key>,
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typename _Pred = std::equal_to<_Key>,
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typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
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typename _Tr = __umap_traits<__cache_default<_Key, _Hash>::value>>
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using __umap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>,
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_Alloc, __detail::_Select1st,
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_Pred, _Hash,
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__detail::_Mod_range_hashing,
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__detail::_Default_ranged_hash,
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__detail::_Prime_rehash_policy, _Tr>;
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/// Base types for unordered_multimap.
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template<bool _Cache>
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using __ummap_traits = __detail::_Hashtable_traits<_Cache, false, false>;
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template<typename _Key,
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typename _Tp,
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typename _Hash = hash<_Key>,
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typename _Pred = std::equal_to<_Key>,
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typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
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typename _Tr = __ummap_traits<__cache_default<_Key, _Hash>::value>>
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using __ummap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>,
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_Alloc, __detail::_Select1st,
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_Pred, _Hash,
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__detail::_Mod_range_hashing,
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__detail::_Default_ranged_hash,
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__detail::_Prime_rehash_policy, _Tr>;
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/**
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* @brief A standard container composed of unique keys (containing
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* at most one of each key value) that associates values of another type
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* with the keys.
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*
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* @ingroup unordered_associative_containers
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*
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* @tparam _Key Type of key objects.
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* @tparam _Tp Type of mapped objects.
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* @tparam _Hash Hashing function object type, defaults to hash<_Value>.
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* @tparam _Pred Predicate function object type, defaults
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* to equal_to<_Value>.
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* @tparam _Alloc Allocator type, defaults to
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* std::allocator<std::pair<const _Key, _Tp>>.
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*
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* Meets the requirements of a <a href="tables.html#65">container</a>, and
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* <a href="tables.html#xx">unordered associative container</a>
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*
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* The resulting value type of the container is std::pair<const _Key, _Tp>.
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*
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* Base is _Hashtable, dispatched at compile time via template
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* alias __umap_hashtable.
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*/
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template<class _Key, class _Tp,
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class _Hash = hash<_Key>,
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class _Pred = std::equal_to<_Key>,
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class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
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class unordered_map
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{
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typedef __umap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable;
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_Hashtable _M_h;
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public:
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// typedefs:
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//@{
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/// Public typedefs.
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typedef typename _Hashtable::key_type key_type;
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typedef typename _Hashtable::value_type value_type;
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typedef typename _Hashtable::mapped_type mapped_type;
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typedef typename _Hashtable::hasher hasher;
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typedef typename _Hashtable::key_equal key_equal;
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typedef typename _Hashtable::allocator_type allocator_type;
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//@}
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//@{
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/// Iterator-related typedefs.
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typedef typename _Hashtable::pointer pointer;
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typedef typename _Hashtable::const_pointer const_pointer;
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typedef typename _Hashtable::reference reference;
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typedef typename _Hashtable::const_reference const_reference;
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typedef typename _Hashtable::iterator iterator;
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typedef typename _Hashtable::const_iterator const_iterator;
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typedef typename _Hashtable::local_iterator local_iterator;
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typedef typename _Hashtable::const_local_iterator const_local_iterator;
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typedef typename _Hashtable::size_type size_type;
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typedef typename _Hashtable::difference_type difference_type;
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//@}
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//construct/destroy/copy
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/// Default constructor.
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unordered_map() = default;
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/**
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* @brief Default constructor creates no elements.
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* @param __n Minimal initial number of buckets.
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* @param __hf A hash functor.
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* @param __eql A key equality functor.
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* @param __a An allocator object.
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*/
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explicit
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unordered_map(size_type __n,
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const hasher& __hf = hasher(),
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const key_equal& __eql = key_equal(),
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const allocator_type& __a = allocator_type())
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: _M_h(__n, __hf, __eql, __a)
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{ }
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/**
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* @brief Builds an %unordered_map from a range.
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* @param __first An input iterator.
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* @param __last An input iterator.
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* @param __n Minimal initial number of buckets.
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* @param __hf A hash functor.
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* @param __eql A key equality functor.
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* @param __a An allocator object.
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*
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* Create an %unordered_map consisting of copies of the elements from
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* [__first,__last). This is linear in N (where N is
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* distance(__first,__last)).
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*/
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template<typename _InputIterator>
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unordered_map(_InputIterator __first, _InputIterator __last,
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size_type __n = 0,
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const hasher& __hf = hasher(),
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const key_equal& __eql = key_equal(),
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const allocator_type& __a = allocator_type())
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: _M_h(__first, __last, __n, __hf, __eql, __a)
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{ }
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/// Copy constructor.
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unordered_map(const unordered_map&) = default;
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/// Move constructor.
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unordered_map(unordered_map&&) = default;
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/**
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* @brief Creates an %unordered_map with no elements.
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* @param __a An allocator object.
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*/
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explicit
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unordered_map(const allocator_type& __a)
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: _M_h(__a)
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{ }
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/*
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* @brief Copy constructor with allocator argument.
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* @param __uset Input %unordered_map to copy.
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* @param __a An allocator object.
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*/
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unordered_map(const unordered_map& __umap,
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const allocator_type& __a)
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: _M_h(__umap._M_h, __a)
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{ }
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/*
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* @brief Move constructor with allocator argument.
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* @param __uset Input %unordered_map to move.
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* @param __a An allocator object.
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*/
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unordered_map(unordered_map&& __umap,
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const allocator_type& __a)
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: _M_h(std::move(__umap._M_h), __a)
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{ }
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/**
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* @brief Builds an %unordered_map from an initializer_list.
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* @param __l An initializer_list.
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* @param __n Minimal initial number of buckets.
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* @param __hf A hash functor.
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* @param __eql A key equality functor.
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* @param __a An allocator object.
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*
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* Create an %unordered_map consisting of copies of the elements in the
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* list. This is linear in N (where N is @a __l.size()).
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*/
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unordered_map(initializer_list<value_type> __l,
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size_type __n = 0,
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const hasher& __hf = hasher(),
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const key_equal& __eql = key_equal(),
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const allocator_type& __a = allocator_type())
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: _M_h(__l, __n, __hf, __eql, __a)
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{ }
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unordered_map(size_type __n, const allocator_type& __a)
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: unordered_map(__n, hasher(), key_equal(), __a)
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{ }
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unordered_map(size_type __n, const hasher& __hf,
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const allocator_type& __a)
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: unordered_map(__n, __hf, key_equal(), __a)
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{ }
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template<typename _InputIterator>
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unordered_map(_InputIterator __first, _InputIterator __last,
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size_type __n,
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const allocator_type& __a)
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: unordered_map(__first, __last, __n, hasher(), key_equal(), __a)
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{ }
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template<typename _InputIterator>
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unordered_map(_InputIterator __first, _InputIterator __last,
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size_type __n, const hasher& __hf,
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const allocator_type& __a)
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: unordered_map(__first, __last, __n, __hf, key_equal(), __a)
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{ }
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unordered_map(initializer_list<value_type> __l,
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size_type __n,
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const allocator_type& __a)
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: unordered_map(__l, __n, hasher(), key_equal(), __a)
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{ }
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unordered_map(initializer_list<value_type> __l,
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size_type __n, const hasher& __hf,
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const allocator_type& __a)
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: unordered_map(__l, __n, __hf, key_equal(), __a)
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{ }
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/// Copy assignment operator.
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unordered_map&
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operator=(const unordered_map&) = default;
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/// Move assignment operator.
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unordered_map&
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operator=(unordered_map&&) = default;
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/**
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* @brief %Unordered_map list assignment operator.
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* @param __l An initializer_list.
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*
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* This function fills an %unordered_map with copies of the elements in
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* the initializer list @a __l.
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*
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* Note that the assignment completely changes the %unordered_map and
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* that the resulting %unordered_map's size is the same as the number
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* of elements assigned. Old data may be lost.
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*/
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unordered_map&
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operator=(initializer_list<value_type> __l)
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{
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_M_h = __l;
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return *this;
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}
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/// Returns the allocator object with which the %unordered_map was
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/// constructed.
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allocator_type
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get_allocator() const noexcept
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{ return _M_h.get_allocator(); }
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// size and capacity:
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/// Returns true if the %unordered_map is empty.
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bool
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empty() const noexcept
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{ return _M_h.empty(); }
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/// Returns the size of the %unordered_map.
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size_type
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size() const noexcept
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{ return _M_h.size(); }
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/// Returns the maximum size of the %unordered_map.
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size_type
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max_size() const noexcept
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{ return _M_h.max_size(); }
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// iterators.
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/**
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* Returns a read/write iterator that points to the first element in the
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* %unordered_map.
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*/
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iterator
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begin() noexcept
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{ return _M_h.begin(); }
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//@{
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/**
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* Returns a read-only (constant) iterator that points to the first
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* element in the %unordered_map.
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*/
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const_iterator
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begin() const noexcept
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{ return _M_h.begin(); }
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const_iterator
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cbegin() const noexcept
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{ return _M_h.begin(); }
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//@}
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/**
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* Returns a read/write iterator that points one past the last element in
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* the %unordered_map.
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*/
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iterator
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end() noexcept
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{ return _M_h.end(); }
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//@{
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/**
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* Returns a read-only (constant) iterator that points one past the last
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* element in the %unordered_map.
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*/
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const_iterator
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end() const noexcept
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{ return _M_h.end(); }
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const_iterator
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cend() const noexcept
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{ return _M_h.end(); }
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//@}
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// modifiers.
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/**
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* @brief Attempts to build and insert a std::pair into the
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* %unordered_map.
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*
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* @param __args Arguments used to generate a new pair instance (see
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* std::piecewise_contruct for passing arguments to each
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* part of the pair constructor).
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*
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* @return A pair, of which the first element is an iterator that points
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* to the possibly inserted pair, and the second is a bool that
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* is true if the pair was actually inserted.
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*
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* This function attempts to build and insert a (key, value) %pair into
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* the %unordered_map.
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* An %unordered_map relies on unique keys and thus a %pair is only
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* inserted if its first element (the key) is not already present in the
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* %unordered_map.
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*
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* Insertion requires amortized constant time.
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*/
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template<typename... _Args>
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std::pair<iterator, bool>
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emplace(_Args&&... __args)
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{ return _M_h.emplace(std::forward<_Args>(__args)...); }
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/**
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* @brief Attempts to build and insert a std::pair into the
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* %unordered_map.
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*
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* @param __pos An iterator that serves as a hint as to where the pair
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* should be inserted.
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* @param __args Arguments used to generate a new pair instance (see
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* std::piecewise_contruct for passing arguments to each
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* part of the pair constructor).
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* @return An iterator that points to the element with key of the
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* std::pair built from @a __args (may or may not be that
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* std::pair).
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*
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* This function is not concerned about whether the insertion took place,
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* and thus does not return a boolean like the single-argument emplace()
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* does.
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* Note that the first parameter is only a hint and can potentially
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* improve the performance of the insertion process. A bad hint would
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* cause no gains in efficiency.
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*
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* See
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* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
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* for more on @a hinting.
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*
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* Insertion requires amortized constant time.
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*/
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template<typename... _Args>
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iterator
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emplace_hint(const_iterator __pos, _Args&&... __args)
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{ return _M_h.emplace_hint(__pos, std::forward<_Args>(__args)...); }
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#if __cplusplus > 201402L
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#define __cpp_lib_unordered_map_try_emplace 201411
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/**
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* @brief Attempts to build and insert a std::pair into the
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* %unordered_map.
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*
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* @param __k Key to use for finding a possibly existing pair in
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* the unordered_map.
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* @param __args Arguments used to generate the .second for a
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* new pair instance.
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*
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* @return A pair, of which the first element is an iterator that points
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* to the possibly inserted pair, and the second is a bool that
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* is true if the pair was actually inserted.
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*
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* This function attempts to build and insert a (key, value) %pair into
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* the %unordered_map.
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* An %unordered_map relies on unique keys and thus a %pair is only
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* inserted if its first element (the key) is not already present in the
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* %unordered_map.
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* If a %pair is not inserted, this function has no effect.
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*
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* Insertion requires amortized constant time.
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*/
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template <typename... _Args>
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pair<iterator, bool>
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try_emplace(const key_type& __k, _Args&&... __args)
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{
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iterator __i = find(__k);
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if (__i == end())
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{
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__i = emplace(std::piecewise_construct,
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std::forward_as_tuple(__k),
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std::forward_as_tuple(
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std::forward<_Args>(__args)...))
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.first;
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return {__i, true};
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}
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return {__i, false};
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}
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// move-capable overload
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template <typename... _Args>
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pair<iterator, bool>
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try_emplace(key_type&& __k, _Args&&... __args)
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{
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iterator __i = find(__k);
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if (__i == end())
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{
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__i = emplace(std::piecewise_construct,
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std::forward_as_tuple(std::move(__k)),
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std::forward_as_tuple(
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std::forward<_Args>(__args)...))
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.first;
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return {__i, true};
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}
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return {__i, false};
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}
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|
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/**
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* @brief Attempts to build and insert a std::pair into the
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* %unordered_map.
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*
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* @param __hint An iterator that serves as a hint as to where the pair
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* should be inserted.
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* @param __k Key to use for finding a possibly existing pair in
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* the unordered_map.
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* @param __args Arguments used to generate the .second for a
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* new pair instance.
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* @return An iterator that points to the element with key of the
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* std::pair built from @a __args (may or may not be that
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* std::pair).
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*
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* This function is not concerned about whether the insertion took place,
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* and thus does not return a boolean like the single-argument emplace()
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* does. However, if insertion did not take place,
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* this function has no effect.
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|
* Note that the first parameter is only a hint and can potentially
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* improve the performance of the insertion process. A bad hint would
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* cause no gains in efficiency.
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*
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* See
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* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
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* for more on @a hinting.
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*
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* Insertion requires amortized constant time.
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*/
|
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template <typename... _Args>
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iterator
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try_emplace(const_iterator __hint, const key_type& __k,
|
|
_Args&&... __args)
|
|
{
|
|
iterator __i = find(__k);
|
|
if (__i == end())
|
|
__i = emplace_hint(__hint, std::piecewise_construct,
|
|
std::forward_as_tuple(__k),
|
|
std::forward_as_tuple(
|
|
std::forward<_Args>(__args)...));
|
|
return __i;
|
|
}
|
|
|
|
// move-capable overload
|
|
template <typename... _Args>
|
|
iterator
|
|
try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
|
|
{
|
|
iterator __i = find(__k);
|
|
if (__i == end())
|
|
__i = emplace_hint(__hint, std::piecewise_construct,
|
|
std::forward_as_tuple(std::move(__k)),
|
|
std::forward_as_tuple(
|
|
std::forward<_Args>(__args)...));
|
|
return __i;
|
|
}
|
|
#endif
|
|
|
|
//@{
|
|
/**
|
|
* @brief Attempts to insert a std::pair into the %unordered_map.
|
|
|
|
* @param __x Pair to be inserted (see std::make_pair for easy
|
|
* creation of pairs).
|
|
*
|
|
* @return A pair, of which the first element is an iterator that
|
|
* points to the possibly inserted pair, and the second is
|
|
* a bool that is true if the pair was actually inserted.
|
|
*
|
|
* This function attempts to insert a (key, value) %pair into the
|
|
* %unordered_map. An %unordered_map relies on unique keys and thus a
|
|
* %pair is only inserted if its first element (the key) is not already
|
|
* present in the %unordered_map.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
std::pair<iterator, bool>
|
|
insert(const value_type& __x)
|
|
{ return _M_h.insert(__x); }
|
|
|
|
template<typename _Pair, typename = typename
|
|
std::enable_if<std::is_constructible<value_type,
|
|
_Pair&&>::value>::type>
|
|
std::pair<iterator, bool>
|
|
insert(_Pair&& __x)
|
|
{ return _M_h.insert(std::forward<_Pair>(__x)); }
|
|
//@}
|
|
|
|
//@{
|
|
/**
|
|
* @brief Attempts to insert a std::pair into the %unordered_map.
|
|
* @param __hint 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 element with key of
|
|
* @a __x (may or may not be the %pair passed in).
|
|
*
|
|
* This function is not concerned about whether the insertion took place,
|
|
* and thus does not return a boolean like the single-argument insert()
|
|
* does. 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.
|
|
*
|
|
* See
|
|
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
|
|
* for more on @a hinting.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
iterator
|
|
insert(const_iterator __hint, const value_type& __x)
|
|
{ return _M_h.insert(__hint, __x); }
|
|
|
|
template<typename _Pair, typename = typename
|
|
std::enable_if<std::is_constructible<value_type,
|
|
_Pair&&>::value>::type>
|
|
iterator
|
|
insert(const_iterator __hint, _Pair&& __x)
|
|
{ return _M_h.insert(__hint, std::forward<_Pair>(__x)); }
|
|
//@}
|
|
|
|
/**
|
|
* @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_h.insert(__first, __last); }
|
|
|
|
/**
|
|
* @brief Attempts to insert a list of elements into the %unordered_map.
|
|
* @param __l A std::initializer_list<value_type> of elements
|
|
* to be inserted.
|
|
*
|
|
* Complexity similar to that of the range constructor.
|
|
*/
|
|
void
|
|
insert(initializer_list<value_type> __l)
|
|
{ _M_h.insert(__l); }
|
|
|
|
|
|
#if __cplusplus > 201402L
|
|
#define __cpp_lib_unordered_map_insertion 201411
|
|
/**
|
|
* @brief Attempts to insert a std::pair into the %unordered_map.
|
|
* @param __k Key to use for finding a possibly existing pair in
|
|
* the map.
|
|
* @param __obj Argument used to generate the .second for a pair
|
|
* instance.
|
|
*
|
|
* @return A pair, of which the first element is an iterator that
|
|
* points to the possibly inserted pair, and the second is
|
|
* a bool that is true if the pair was actually inserted.
|
|
*
|
|
* This function attempts to insert a (key, value) %pair into the
|
|
* %unordered_map. An %unordered_map relies on unique keys and thus a
|
|
* %pair is only inserted if its first element (the key) is not already
|
|
* present in the %unordered_map.
|
|
* If the %pair was already in the %unordered_map, the .second of
|
|
* the %pair is assigned from __obj.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
template <typename _Obj>
|
|
pair<iterator, bool>
|
|
insert_or_assign(const key_type& __k, _Obj&& __obj)
|
|
{
|
|
iterator __i = find(__k);
|
|
if (__i == end())
|
|
{
|
|
__i = emplace(std::piecewise_construct,
|
|
std::forward_as_tuple(__k),
|
|
std::forward_as_tuple(std::forward<_Obj>(__obj)))
|
|
.first;
|
|
return {__i, true};
|
|
}
|
|
(*__i).second = std::forward<_Obj>(__obj);
|
|
return {__i, false};
|
|
}
|
|
|
|
// move-capable overload
|
|
template <typename _Obj>
|
|
pair<iterator, bool>
|
|
insert_or_assign(key_type&& __k, _Obj&& __obj)
|
|
{
|
|
iterator __i = find(__k);
|
|
if (__i == end())
|
|
{
|
|
__i = emplace(std::piecewise_construct,
|
|
std::forward_as_tuple(std::move(__k)),
|
|
std::forward_as_tuple(std::forward<_Obj>(__obj)))
|
|
.first;
|
|
return {__i, true};
|
|
}
|
|
(*__i).second = std::forward<_Obj>(__obj);
|
|
return {__i, false};
|
|
}
|
|
|
|
/**
|
|
* @brief Attempts to insert a std::pair into the %unordered_map.
|
|
* @param __hint An iterator that serves as a hint as to where the
|
|
* pair should be inserted.
|
|
* @param __k Key to use for finding a possibly existing pair in
|
|
* the unordered_map.
|
|
* @param __obj Argument used to generate the .second for a pair
|
|
* instance.
|
|
* @return An iterator that points to the element with key of
|
|
* @a __x (may or may not be the %pair passed in).
|
|
*
|
|
* This function is not concerned about whether the insertion took place,
|
|
* and thus does not return a boolean like the single-argument insert()
|
|
* does.
|
|
* If the %pair was already in the %unordered map, the .second of
|
|
* the %pair is assigned from __obj.
|
|
* 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.
|
|
*
|
|
* See
|
|
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
|
|
* for more on @a hinting.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
template <typename _Obj>
|
|
iterator
|
|
insert_or_assign(const_iterator __hint, const key_type& __k,
|
|
_Obj&& __obj)
|
|
{
|
|
iterator __i = find(__k);
|
|
if (__i == end())
|
|
{
|
|
return emplace_hint(__hint, std::piecewise_construct,
|
|
std::forward_as_tuple(__k),
|
|
std::forward_as_tuple(
|
|
std::forward<_Obj>(__obj)));
|
|
}
|
|
(*__i).second = std::forward<_Obj>(__obj);
|
|
return __i;
|
|
}
|
|
|
|
// move-capable overload
|
|
template <typename _Obj>
|
|
iterator
|
|
insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
|
|
{
|
|
iterator __i = find(__k);
|
|
if (__i == end())
|
|
{
|
|
return emplace_hint(__hint, std::piecewise_construct,
|
|
std::forward_as_tuple(std::move(__k)),
|
|
std::forward_as_tuple(
|
|
std::forward<_Obj>(__obj)));
|
|
}
|
|
(*__i).second = std::forward<_Obj>(__obj);
|
|
return __i;
|
|
}
|
|
#endif
|
|
|
|
//@{
|
|
/**
|
|
* @brief Erases an element from an %unordered_map.
|
|
* @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 an %unordered_map.
|
|
* 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_h.erase(__position); }
|
|
|
|
// LWG 2059.
|
|
iterator
|
|
erase(iterator __position)
|
|
{ return _M_h.erase(__position); }
|
|
//@}
|
|
|
|
/**
|
|
* @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 the elements located by the given key from
|
|
* an %unordered_map. For an %unordered_map the result of this function
|
|
* can only be 0 (not present) or 1 (present).
|
|
* 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_h.erase(__x); }
|
|
|
|
/**
|
|
* @brief Erases a [__first,__last) range of elements from an
|
|
* %unordered_map.
|
|
* @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 an %unordered_map.
|
|
* Note that this function only erases the elements, 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 __first, const_iterator __last)
|
|
{ return _M_h.erase(__first, __last); }
|
|
|
|
/**
|
|
* Erases all elements in an %unordered_map.
|
|
* 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() noexcept
|
|
{ _M_h.clear(); }
|
|
|
|
/**
|
|
* @brief Swaps data with another %unordered_map.
|
|
* @param __x An %unordered_map of the same element and allocator
|
|
* types.
|
|
*
|
|
* This exchanges the elements between two %unordered_map in constant
|
|
* time.
|
|
* Note that the global std::swap() function is specialized such that
|
|
* std::swap(m1,m2) will feed to this function.
|
|
*/
|
|
void
|
|
swap(unordered_map& __x)
|
|
noexcept( noexcept(_M_h.swap(__x._M_h)) )
|
|
{ _M_h.swap(__x._M_h); }
|
|
|
|
// observers.
|
|
|
|
/// Returns the hash functor object with which the %unordered_map was
|
|
/// constructed.
|
|
hasher
|
|
hash_function() const
|
|
{ return _M_h.hash_function(); }
|
|
|
|
/// Returns the key comparison object with which the %unordered_map was
|
|
/// constructed.
|
|
key_equal
|
|
key_eq() const
|
|
{ return _M_h.key_eq(); }
|
|
|
|
// lookup.
|
|
|
|
//@{
|
|
/**
|
|
* @brief Tries to locate an element in an %unordered_map.
|
|
* @param __x Key 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 element. If unsuccessful it returns the
|
|
* past-the-end ( @c end() ) iterator.
|
|
*/
|
|
iterator
|
|
find(const key_type& __x)
|
|
{ return _M_h.find(__x); }
|
|
|
|
const_iterator
|
|
find(const key_type& __x) const
|
|
{ return _M_h.find(__x); }
|
|
//@}
|
|
|
|
/**
|
|
* @brief Finds the number of elements.
|
|
* @param __x Key to count.
|
|
* @return Number of elements with specified key.
|
|
*
|
|
* This function only makes sense for %unordered_multimap; for
|
|
* %unordered_map the result will either be 0 (not present) or 1
|
|
* (present).
|
|
*/
|
|
size_type
|
|
count(const key_type& __x) const
|
|
{ return _M_h.count(__x); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Finds a subsequence matching given key.
|
|
* @param __x Key to be located.
|
|
* @return Pair of iterators that possibly points to the subsequence
|
|
* matching given key.
|
|
*
|
|
* This function probably only makes sense for %unordered_multimap.
|
|
*/
|
|
std::pair<iterator, iterator>
|
|
equal_range(const key_type& __x)
|
|
{ return _M_h.equal_range(__x); }
|
|
|
|
std::pair<const_iterator, const_iterator>
|
|
equal_range(const key_type& __x) const
|
|
{ return _M_h.equal_range(__x); }
|
|
//@}
|
|
|
|
//@{
|
|
/**
|
|
* @brief Subscript ( @c [] ) access to %unordered_map data.
|
|
* @param __k The key for which data should be retrieved.
|
|
* @return A reference to the data of the (key,data) %pair.
|
|
*
|
|
* Allows for easy lookup with the subscript ( @c [] )operator. Returns
|
|
* data associated with the key specified in subscript. If the key does
|
|
* not exist, a pair with that key is created using default values, which
|
|
* is then returned.
|
|
*
|
|
* Lookup requires constant time.
|
|
*/
|
|
mapped_type&
|
|
operator[](const key_type& __k)
|
|
{ return _M_h[__k]; }
|
|
|
|
mapped_type&
|
|
operator[](key_type&& __k)
|
|
{ return _M_h[std::move(__k)]; }
|
|
//@}
|
|
|
|
//@{
|
|
/**
|
|
* @brief Access to %unordered_map data.
|
|
* @param __k The key for which data should be retrieved.
|
|
* @return A reference to the data whose key is equal to @a __k, if
|
|
* such a data is present in the %unordered_map.
|
|
* @throw std::out_of_range If no such data is present.
|
|
*/
|
|
mapped_type&
|
|
at(const key_type& __k)
|
|
{ return _M_h.at(__k); }
|
|
|
|
const mapped_type&
|
|
at(const key_type& __k) const
|
|
{ return _M_h.at(__k); }
|
|
//@}
|
|
|
|
// bucket interface.
|
|
|
|
/// Returns the number of buckets of the %unordered_map.
|
|
size_type
|
|
bucket_count() const noexcept
|
|
{ return _M_h.bucket_count(); }
|
|
|
|
/// Returns the maximum number of buckets of the %unordered_map.
|
|
size_type
|
|
max_bucket_count() const noexcept
|
|
{ return _M_h.max_bucket_count(); }
|
|
|
|
/*
|
|
* @brief Returns the number of elements in a given bucket.
|
|
* @param __n A bucket index.
|
|
* @return The number of elements in the bucket.
|
|
*/
|
|
size_type
|
|
bucket_size(size_type __n) const
|
|
{ return _M_h.bucket_size(__n); }
|
|
|
|
/*
|
|
* @brief Returns the bucket index of a given element.
|
|
* @param __key A key instance.
|
|
* @return The key bucket index.
|
|
*/
|
|
size_type
|
|
bucket(const key_type& __key) const
|
|
{ return _M_h.bucket(__key); }
|
|
|
|
/**
|
|
* @brief Returns a read/write iterator pointing to the first bucket
|
|
* element.
|
|
* @param __n The bucket index.
|
|
* @return A read/write local iterator.
|
|
*/
|
|
local_iterator
|
|
begin(size_type __n)
|
|
{ return _M_h.begin(__n); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Returns a read-only (constant) iterator pointing to the first
|
|
* bucket element.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
const_local_iterator
|
|
begin(size_type __n) const
|
|
{ return _M_h.begin(__n); }
|
|
|
|
const_local_iterator
|
|
cbegin(size_type __n) const
|
|
{ return _M_h.cbegin(__n); }
|
|
//@}
|
|
|
|
/**
|
|
* @brief Returns a read/write iterator pointing to one past the last
|
|
* bucket elements.
|
|
* @param __n The bucket index.
|
|
* @return A read/write local iterator.
|
|
*/
|
|
local_iterator
|
|
end(size_type __n)
|
|
{ return _M_h.end(__n); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Returns a read-only (constant) iterator pointing to one past
|
|
* the last bucket elements.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
const_local_iterator
|
|
end(size_type __n) const
|
|
{ return _M_h.end(__n); }
|
|
|
|
const_local_iterator
|
|
cend(size_type __n) const
|
|
{ return _M_h.cend(__n); }
|
|
//@}
|
|
|
|
// hash policy.
|
|
|
|
/// Returns the average number of elements per bucket.
|
|
float
|
|
load_factor() const noexcept
|
|
{ return _M_h.load_factor(); }
|
|
|
|
/// Returns a positive number that the %unordered_map tries to keep the
|
|
/// load factor less than or equal to.
|
|
float
|
|
max_load_factor() const noexcept
|
|
{ return _M_h.max_load_factor(); }
|
|
|
|
/**
|
|
* @brief Change the %unordered_map maximum load factor.
|
|
* @param __z The new maximum load factor.
|
|
*/
|
|
void
|
|
max_load_factor(float __z)
|
|
{ _M_h.max_load_factor(__z); }
|
|
|
|
/**
|
|
* @brief May rehash the %unordered_map.
|
|
* @param __n The new number of buckets.
|
|
*
|
|
* Rehash will occur only if the new number of buckets respect the
|
|
* %unordered_map maximum load factor.
|
|
*/
|
|
void
|
|
rehash(size_type __n)
|
|
{ _M_h.rehash(__n); }
|
|
|
|
/**
|
|
* @brief Prepare the %unordered_map for a specified number of
|
|
* elements.
|
|
* @param __n Number of elements required.
|
|
*
|
|
* Same as rehash(ceil(n / max_load_factor())).
|
|
*/
|
|
void
|
|
reserve(size_type __n)
|
|
{ _M_h.reserve(__n); }
|
|
|
|
template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1,
|
|
typename _Alloc1>
|
|
friend bool
|
|
operator==(const unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&,
|
|
const unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&);
|
|
};
|
|
|
|
/**
|
|
* @brief A standard container composed of equivalent keys
|
|
* (possibly containing multiple of each key value) that associates
|
|
* values of another type with the keys.
|
|
*
|
|
* @ingroup unordered_associative_containers
|
|
*
|
|
* @tparam _Key Type of key objects.
|
|
* @tparam _Tp Type of mapped objects.
|
|
* @tparam _Hash Hashing function object type, defaults to hash<_Value>.
|
|
* @tparam _Pred Predicate function object type, defaults
|
|
* to equal_to<_Value>.
|
|
* @tparam _Alloc Allocator type, defaults to
|
|
* std::allocator<std::pair<const _Key, _Tp>>.
|
|
*
|
|
* Meets the requirements of a <a href="tables.html#65">container</a>, and
|
|
* <a href="tables.html#xx">unordered associative container</a>
|
|
*
|
|
* The resulting value type of the container is std::pair<const _Key, _Tp>.
|
|
*
|
|
* Base is _Hashtable, dispatched at compile time via template
|
|
* alias __ummap_hashtable.
|
|
*/
|
|
template<class _Key, class _Tp,
|
|
class _Hash = hash<_Key>,
|
|
class _Pred = std::equal_to<_Key>,
|
|
class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
|
|
class unordered_multimap
|
|
{
|
|
typedef __ummap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable;
|
|
_Hashtable _M_h;
|
|
|
|
public:
|
|
// typedefs:
|
|
//@{
|
|
/// Public typedefs.
|
|
typedef typename _Hashtable::key_type key_type;
|
|
typedef typename _Hashtable::value_type value_type;
|
|
typedef typename _Hashtable::mapped_type mapped_type;
|
|
typedef typename _Hashtable::hasher hasher;
|
|
typedef typename _Hashtable::key_equal key_equal;
|
|
typedef typename _Hashtable::allocator_type allocator_type;
|
|
//@}
|
|
|
|
//@{
|
|
/// Iterator-related typedefs.
|
|
typedef typename _Hashtable::pointer pointer;
|
|
typedef typename _Hashtable::const_pointer const_pointer;
|
|
typedef typename _Hashtable::reference reference;
|
|
typedef typename _Hashtable::const_reference const_reference;
|
|
typedef typename _Hashtable::iterator iterator;
|
|
typedef typename _Hashtable::const_iterator const_iterator;
|
|
typedef typename _Hashtable::local_iterator local_iterator;
|
|
typedef typename _Hashtable::const_local_iterator const_local_iterator;
|
|
typedef typename _Hashtable::size_type size_type;
|
|
typedef typename _Hashtable::difference_type difference_type;
|
|
//@}
|
|
|
|
//construct/destroy/copy
|
|
|
|
/// Default constructor.
|
|
unordered_multimap() = default;
|
|
|
|
/**
|
|
* @brief Default constructor creates no elements.
|
|
* @param __n Mnimal initial number of buckets.
|
|
* @param __hf A hash functor.
|
|
* @param __eql A key equality functor.
|
|
* @param __a An allocator object.
|
|
*/
|
|
explicit
|
|
unordered_multimap(size_type __n,
|
|
const hasher& __hf = hasher(),
|
|
const key_equal& __eql = key_equal(),
|
|
const allocator_type& __a = allocator_type())
|
|
: _M_h(__n, __hf, __eql, __a)
|
|
{ }
|
|
|
|
/**
|
|
* @brief Builds an %unordered_multimap from a range.
|
|
* @param __first An input iterator.
|
|
* @param __last An input iterator.
|
|
* @param __n Minimal initial number of buckets.
|
|
* @param __hf A hash functor.
|
|
* @param __eql A key equality functor.
|
|
* @param __a An allocator object.
|
|
*
|
|
* Create an %unordered_multimap consisting of copies of the elements
|
|
* from [__first,__last). This is linear in N (where N is
|
|
* distance(__first,__last)).
|
|
*/
|
|
template<typename _InputIterator>
|
|
unordered_multimap(_InputIterator __first, _InputIterator __last,
|
|
size_type __n = 0,
|
|
const hasher& __hf = hasher(),
|
|
const key_equal& __eql = key_equal(),
|
|
const allocator_type& __a = allocator_type())
|
|
: _M_h(__first, __last, __n, __hf, __eql, __a)
|
|
{ }
|
|
|
|
/// Copy constructor.
|
|
unordered_multimap(const unordered_multimap&) = default;
|
|
|
|
/// Move constructor.
|
|
unordered_multimap(unordered_multimap&&) = default;
|
|
|
|
/**
|
|
* @brief Creates an %unordered_multimap with no elements.
|
|
* @param __a An allocator object.
|
|
*/
|
|
explicit
|
|
unordered_multimap(const allocator_type& __a)
|
|
: _M_h(__a)
|
|
{ }
|
|
|
|
/*
|
|
* @brief Copy constructor with allocator argument.
|
|
* @param __uset Input %unordered_multimap to copy.
|
|
* @param __a An allocator object.
|
|
*/
|
|
unordered_multimap(const unordered_multimap& __ummap,
|
|
const allocator_type& __a)
|
|
: _M_h(__ummap._M_h, __a)
|
|
{ }
|
|
|
|
/*
|
|
* @brief Move constructor with allocator argument.
|
|
* @param __uset Input %unordered_multimap to move.
|
|
* @param __a An allocator object.
|
|
*/
|
|
unordered_multimap(unordered_multimap&& __ummap,
|
|
const allocator_type& __a)
|
|
: _M_h(std::move(__ummap._M_h), __a)
|
|
{ }
|
|
|
|
/**
|
|
* @brief Builds an %unordered_multimap from an initializer_list.
|
|
* @param __l An initializer_list.
|
|
* @param __n Minimal initial number of buckets.
|
|
* @param __hf A hash functor.
|
|
* @param __eql A key equality functor.
|
|
* @param __a An allocator object.
|
|
*
|
|
* Create an %unordered_multimap consisting of copies of the elements in
|
|
* the list. This is linear in N (where N is @a __l.size()).
|
|
*/
|
|
unordered_multimap(initializer_list<value_type> __l,
|
|
size_type __n = 0,
|
|
const hasher& __hf = hasher(),
|
|
const key_equal& __eql = key_equal(),
|
|
const allocator_type& __a = allocator_type())
|
|
: _M_h(__l, __n, __hf, __eql, __a)
|
|
{ }
|
|
|
|
unordered_multimap(size_type __n, const allocator_type& __a)
|
|
: unordered_multimap(__n, hasher(), key_equal(), __a)
|
|
{ }
|
|
|
|
unordered_multimap(size_type __n, const hasher& __hf,
|
|
const allocator_type& __a)
|
|
: unordered_multimap(__n, __hf, key_equal(), __a)
|
|
{ }
|
|
|
|
template<typename _InputIterator>
|
|
unordered_multimap(_InputIterator __first, _InputIterator __last,
|
|
size_type __n,
|
|
const allocator_type& __a)
|
|
: unordered_multimap(__first, __last, __n, hasher(), key_equal(), __a)
|
|
{ }
|
|
|
|
template<typename _InputIterator>
|
|
unordered_multimap(_InputIterator __first, _InputIterator __last,
|
|
size_type __n, const hasher& __hf,
|
|
const allocator_type& __a)
|
|
: unordered_multimap(__first, __last, __n, __hf, key_equal(), __a)
|
|
{ }
|
|
|
|
unordered_multimap(initializer_list<value_type> __l,
|
|
size_type __n,
|
|
const allocator_type& __a)
|
|
: unordered_multimap(__l, __n, hasher(), key_equal(), __a)
|
|
{ }
|
|
|
|
unordered_multimap(initializer_list<value_type> __l,
|
|
size_type __n, const hasher& __hf,
|
|
const allocator_type& __a)
|
|
: unordered_multimap(__l, __n, __hf, key_equal(), __a)
|
|
{ }
|
|
|
|
/// Copy assignment operator.
|
|
unordered_multimap&
|
|
operator=(const unordered_multimap&) = default;
|
|
|
|
/// Move assignment operator.
|
|
unordered_multimap&
|
|
operator=(unordered_multimap&&) = default;
|
|
|
|
/**
|
|
* @brief %Unordered_multimap list assignment operator.
|
|
* @param __l An initializer_list.
|
|
*
|
|
* This function fills an %unordered_multimap with copies of the elements
|
|
* in the initializer list @a __l.
|
|
*
|
|
* Note that the assignment completely changes the %unordered_multimap
|
|
* and that the resulting %unordered_multimap's size is the same as the
|
|
* number of elements assigned. Old data may be lost.
|
|
*/
|
|
unordered_multimap&
|
|
operator=(initializer_list<value_type> __l)
|
|
{
|
|
_M_h = __l;
|
|
return *this;
|
|
}
|
|
|
|
/// Returns the allocator object with which the %unordered_multimap was
|
|
/// constructed.
|
|
allocator_type
|
|
get_allocator() const noexcept
|
|
{ return _M_h.get_allocator(); }
|
|
|
|
// size and capacity:
|
|
|
|
/// Returns true if the %unordered_multimap is empty.
|
|
bool
|
|
empty() const noexcept
|
|
{ return _M_h.empty(); }
|
|
|
|
/// Returns the size of the %unordered_multimap.
|
|
size_type
|
|
size() const noexcept
|
|
{ return _M_h.size(); }
|
|
|
|
/// Returns the maximum size of the %unordered_multimap.
|
|
size_type
|
|
max_size() const noexcept
|
|
{ return _M_h.max_size(); }
|
|
|
|
// iterators.
|
|
|
|
/**
|
|
* Returns a read/write iterator that points to the first element in the
|
|
* %unordered_multimap.
|
|
*/
|
|
iterator
|
|
begin() noexcept
|
|
{ return _M_h.begin(); }
|
|
|
|
//@{
|
|
/**
|
|
* Returns a read-only (constant) iterator that points to the first
|
|
* element in the %unordered_multimap.
|
|
*/
|
|
const_iterator
|
|
begin() const noexcept
|
|
{ return _M_h.begin(); }
|
|
|
|
const_iterator
|
|
cbegin() const noexcept
|
|
{ return _M_h.begin(); }
|
|
//@}
|
|
|
|
/**
|
|
* Returns a read/write iterator that points one past the last element in
|
|
* the %unordered_multimap.
|
|
*/
|
|
iterator
|
|
end() noexcept
|
|
{ return _M_h.end(); }
|
|
|
|
//@{
|
|
/**
|
|
* Returns a read-only (constant) iterator that points one past the last
|
|
* element in the %unordered_multimap.
|
|
*/
|
|
const_iterator
|
|
end() const noexcept
|
|
{ return _M_h.end(); }
|
|
|
|
const_iterator
|
|
cend() const noexcept
|
|
{ return _M_h.end(); }
|
|
//@}
|
|
|
|
// modifiers.
|
|
|
|
/**
|
|
* @brief Attempts to build and insert a std::pair into the
|
|
* %unordered_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 pair.
|
|
*
|
|
* This function attempts to build and insert a (key, value) %pair into
|
|
* the %unordered_multimap.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
template<typename... _Args>
|
|
iterator
|
|
emplace(_Args&&... __args)
|
|
{ return _M_h.emplace(std::forward<_Args>(__args)...); }
|
|
|
|
/**
|
|
* @brief Attempts to build and insert a std::pair into the
|
|
* %unordered_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 element with key of the
|
|
* std::pair built from @a __args.
|
|
*
|
|
* 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.
|
|
*
|
|
* See
|
|
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
|
|
* for more on @a hinting.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
template<typename... _Args>
|
|
iterator
|
|
emplace_hint(const_iterator __pos, _Args&&... __args)
|
|
{ return _M_h.emplace_hint(__pos, std::forward<_Args>(__args)...); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Inserts a std::pair into the %unordered_multimap.
|
|
* @param __x Pair to be inserted (see std::make_pair for easy
|
|
* creation of pairs).
|
|
*
|
|
* @return An iterator that points to the inserted pair.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
iterator
|
|
insert(const value_type& __x)
|
|
{ return _M_h.insert(__x); }
|
|
|
|
template<typename _Pair, typename = typename
|
|
std::enable_if<std::is_constructible<value_type,
|
|
_Pair&&>::value>::type>
|
|
iterator
|
|
insert(_Pair&& __x)
|
|
{ return _M_h.insert(std::forward<_Pair>(__x)); }
|
|
//@}
|
|
|
|
//@{
|
|
/**
|
|
* @brief Inserts a std::pair into the %unordered_multimap.
|
|
* @param __hint 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 element with key of
|
|
* @a __x (may or may not be the %pair passed in).
|
|
*
|
|
* 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.
|
|
*
|
|
* See
|
|
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
|
|
* for more on @a hinting.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
iterator
|
|
insert(const_iterator __hint, const value_type& __x)
|
|
{ return _M_h.insert(__hint, __x); }
|
|
|
|
template<typename _Pair, typename = typename
|
|
std::enable_if<std::is_constructible<value_type,
|
|
_Pair&&>::value>::type>
|
|
iterator
|
|
insert(const_iterator __hint, _Pair&& __x)
|
|
{ return _M_h.insert(__hint, std::forward<_Pair>(__x)); }
|
|
//@}
|
|
|
|
/**
|
|
* @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_h.insert(__first, __last); }
|
|
|
|
/**
|
|
* @brief Attempts to insert a list of elements into the
|
|
* %unordered_multimap.
|
|
* @param __l A std::initializer_list<value_type> of elements
|
|
* to be inserted.
|
|
*
|
|
* Complexity similar to that of the range constructor.
|
|
*/
|
|
void
|
|
insert(initializer_list<value_type> __l)
|
|
{ _M_h.insert(__l); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Erases an element from an %unordered_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 an %unordered_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_h.erase(__position); }
|
|
|
|
// LWG 2059.
|
|
iterator
|
|
erase(iterator __position)
|
|
{ return _M_h.erase(__position); }
|
|
//@}
|
|
|
|
/**
|
|
* @brief Erases elements according to the provided key.
|
|
* @param __x Key of elements to be erased.
|
|
* @return The number of elements erased.
|
|
*
|
|
* This function erases all the elements located by the given key from
|
|
* an %unordered_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_h.erase(__x); }
|
|
|
|
/**
|
|
* @brief Erases a [__first,__last) range of elements from an
|
|
* %unordered_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 an
|
|
* %unordered_multimap.
|
|
* Note that this function only erases the elements, 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 __first, const_iterator __last)
|
|
{ return _M_h.erase(__first, __last); }
|
|
|
|
/**
|
|
* Erases all elements in an %unordered_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() noexcept
|
|
{ _M_h.clear(); }
|
|
|
|
/**
|
|
* @brief Swaps data with another %unordered_multimap.
|
|
* @param __x An %unordered_multimap of the same element and allocator
|
|
* types.
|
|
*
|
|
* This exchanges the elements between two %unordered_multimap in
|
|
* constant time.
|
|
* Note that the global std::swap() function is specialized such that
|
|
* std::swap(m1,m2) will feed to this function.
|
|
*/
|
|
void
|
|
swap(unordered_multimap& __x)
|
|
noexcept( noexcept(_M_h.swap(__x._M_h)) )
|
|
{ _M_h.swap(__x._M_h); }
|
|
|
|
// observers.
|
|
|
|
/// Returns the hash functor object with which the %unordered_multimap
|
|
/// was constructed.
|
|
hasher
|
|
hash_function() const
|
|
{ return _M_h.hash_function(); }
|
|
|
|
/// Returns the key comparison object with which the %unordered_multimap
|
|
/// was constructed.
|
|
key_equal
|
|
key_eq() const
|
|
{ return _M_h.key_eq(); }
|
|
|
|
// lookup.
|
|
|
|
//@{
|
|
/**
|
|
* @brief Tries to locate an element in an %unordered_multimap.
|
|
* @param __x Key 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 element. If unsuccessful it returns the
|
|
* past-the-end ( @c end() ) iterator.
|
|
*/
|
|
iterator
|
|
find(const key_type& __x)
|
|
{ return _M_h.find(__x); }
|
|
|
|
const_iterator
|
|
find(const key_type& __x) const
|
|
{ return _M_h.find(__x); }
|
|
//@}
|
|
|
|
/**
|
|
* @brief Finds the number of elements.
|
|
* @param __x Key to count.
|
|
* @return Number of elements with specified key.
|
|
*/
|
|
size_type
|
|
count(const key_type& __x) const
|
|
{ return _M_h.count(__x); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Finds a subsequence matching given key.
|
|
* @param __x Key to be located.
|
|
* @return Pair of iterators that possibly points to the subsequence
|
|
* matching given key.
|
|
*/
|
|
std::pair<iterator, iterator>
|
|
equal_range(const key_type& __x)
|
|
{ return _M_h.equal_range(__x); }
|
|
|
|
std::pair<const_iterator, const_iterator>
|
|
equal_range(const key_type& __x) const
|
|
{ return _M_h.equal_range(__x); }
|
|
//@}
|
|
|
|
// bucket interface.
|
|
|
|
/// Returns the number of buckets of the %unordered_multimap.
|
|
size_type
|
|
bucket_count() const noexcept
|
|
{ return _M_h.bucket_count(); }
|
|
|
|
/// Returns the maximum number of buckets of the %unordered_multimap.
|
|
size_type
|
|
max_bucket_count() const noexcept
|
|
{ return _M_h.max_bucket_count(); }
|
|
|
|
/*
|
|
* @brief Returns the number of elements in a given bucket.
|
|
* @param __n A bucket index.
|
|
* @return The number of elements in the bucket.
|
|
*/
|
|
size_type
|
|
bucket_size(size_type __n) const
|
|
{ return _M_h.bucket_size(__n); }
|
|
|
|
/*
|
|
* @brief Returns the bucket index of a given element.
|
|
* @param __key A key instance.
|
|
* @return The key bucket index.
|
|
*/
|
|
size_type
|
|
bucket(const key_type& __key) const
|
|
{ return _M_h.bucket(__key); }
|
|
|
|
/**
|
|
* @brief Returns a read/write iterator pointing to the first bucket
|
|
* element.
|
|
* @param __n The bucket index.
|
|
* @return A read/write local iterator.
|
|
*/
|
|
local_iterator
|
|
begin(size_type __n)
|
|
{ return _M_h.begin(__n); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Returns a read-only (constant) iterator pointing to the first
|
|
* bucket element.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
const_local_iterator
|
|
begin(size_type __n) const
|
|
{ return _M_h.begin(__n); }
|
|
|
|
const_local_iterator
|
|
cbegin(size_type __n) const
|
|
{ return _M_h.cbegin(__n); }
|
|
//@}
|
|
|
|
/**
|
|
* @brief Returns a read/write iterator pointing to one past the last
|
|
* bucket elements.
|
|
* @param __n The bucket index.
|
|
* @return A read/write local iterator.
|
|
*/
|
|
local_iterator
|
|
end(size_type __n)
|
|
{ return _M_h.end(__n); }
|
|
|
|
//@{
|
|
/**
|
|
* @brief Returns a read-only (constant) iterator pointing to one past
|
|
* the last bucket elements.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
const_local_iterator
|
|
end(size_type __n) const
|
|
{ return _M_h.end(__n); }
|
|
|
|
const_local_iterator
|
|
cend(size_type __n) const
|
|
{ return _M_h.cend(__n); }
|
|
//@}
|
|
|
|
// hash policy.
|
|
|
|
/// Returns the average number of elements per bucket.
|
|
float
|
|
load_factor() const noexcept
|
|
{ return _M_h.load_factor(); }
|
|
|
|
/// Returns a positive number that the %unordered_multimap tries to keep
|
|
/// the load factor less than or equal to.
|
|
float
|
|
max_load_factor() const noexcept
|
|
{ return _M_h.max_load_factor(); }
|
|
|
|
/**
|
|
* @brief Change the %unordered_multimap maximum load factor.
|
|
* @param __z The new maximum load factor.
|
|
*/
|
|
void
|
|
max_load_factor(float __z)
|
|
{ _M_h.max_load_factor(__z); }
|
|
|
|
/**
|
|
* @brief May rehash the %unordered_multimap.
|
|
* @param __n The new number of buckets.
|
|
*
|
|
* Rehash will occur only if the new number of buckets respect the
|
|
* %unordered_multimap maximum load factor.
|
|
*/
|
|
void
|
|
rehash(size_type __n)
|
|
{ _M_h.rehash(__n); }
|
|
|
|
/**
|
|
* @brief Prepare the %unordered_multimap for a specified number of
|
|
* elements.
|
|
* @param __n Number of elements required.
|
|
*
|
|
* Same as rehash(ceil(n / max_load_factor())).
|
|
*/
|
|
void
|
|
reserve(size_type __n)
|
|
{ _M_h.reserve(__n); }
|
|
|
|
template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1,
|
|
typename _Alloc1>
|
|
friend bool
|
|
operator==(const unordered_multimap<_Key1, _Tp1,
|
|
_Hash1, _Pred1, _Alloc1>&,
|
|
const unordered_multimap<_Key1, _Tp1,
|
|
_Hash1, _Pred1, _Alloc1>&);
|
|
};
|
|
|
|
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
|
|
inline void
|
|
swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
|
|
unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
|
|
noexcept(noexcept(__x.swap(__y)))
|
|
{ __x.swap(__y); }
|
|
|
|
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
|
|
inline void
|
|
swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
|
|
unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
|
|
noexcept(noexcept(__x.swap(__y)))
|
|
{ __x.swap(__y); }
|
|
|
|
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator==(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
|
|
{ return __x._M_h._M_equal(__y._M_h); }
|
|
|
|
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator!=(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
|
|
{ return !(__x == __y); }
|
|
|
|
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator==(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
|
|
{ return __x._M_h._M_equal(__y._M_h); }
|
|
|
|
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator!=(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
|
|
{ return !(__x == __y); }
|
|
|
|
_GLIBCXX_END_NAMESPACE_CONTAINER
|
|
} // namespace std
|
|
|
|
#endif /* _UNORDERED_MAP_H */
|