1885 lines
62 KiB
C++
1885 lines
62 KiB
C++
// unordered_set implementation -*- C++ -*-
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// Copyright (C) 2010-2022 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_set.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_set}
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*/
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#ifndef _UNORDERED_SET_H
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#define _UNORDERED_SET_H
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namespace std _GLIBCXX_VISIBILITY(default)
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{
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_GLIBCXX_BEGIN_NAMESPACE_VERSION
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_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
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/// Base types for unordered_set.
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template<bool _Cache>
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using __uset_traits = __detail::_Hashtable_traits<_Cache, true, true>;
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template<typename _Value,
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typename _Hash = hash<_Value>,
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typename _Pred = std::equal_to<_Value>,
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typename _Alloc = std::allocator<_Value>,
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typename _Tr = __uset_traits<__cache_default<_Value, _Hash>::value>>
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using __uset_hashtable = _Hashtable<_Value, _Value, _Alloc,
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__detail::_Identity, _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_multiset.
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template<bool _Cache>
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using __umset_traits = __detail::_Hashtable_traits<_Cache, true, false>;
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template<typename _Value,
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typename _Hash = hash<_Value>,
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typename _Pred = std::equal_to<_Value>,
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typename _Alloc = std::allocator<_Value>,
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typename _Tr = __umset_traits<__cache_default<_Value, _Hash>::value>>
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using __umset_hashtable = _Hashtable<_Value, _Value, _Alloc,
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__detail::_Identity,
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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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template<class _Value, class _Hash, class _Pred, class _Alloc>
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class unordered_multiset;
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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) in which the elements' keys are
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* the elements themselves.
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*
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* @ingroup unordered_associative_containers
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*
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* @tparam _Value Type of key 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 to
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* equal_to<_Value>.
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*
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* @tparam _Alloc Allocator type, defaults to allocator<_Key>.
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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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* Base is _Hashtable, dispatched at compile time via template
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* alias __uset_hashtable.
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*/
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template<typename _Value,
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typename _Hash = hash<_Value>,
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typename _Pred = equal_to<_Value>,
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typename _Alloc = allocator<_Value>>
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class unordered_set
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{
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typedef __uset_hashtable<_Value, _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::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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#if __cplusplus > 201402L
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using node_type = typename _Hashtable::node_type;
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using insert_return_type = typename _Hashtable::insert_return_type;
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#endif
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// construct/destroy/copy
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/// Default constructor.
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unordered_set() = 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_set(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_set 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_set 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_set(_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_set(const unordered_set&) = default;
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/// Move constructor.
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unordered_set(unordered_set&&) = default;
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/**
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* @brief Creates an %unordered_set 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_set(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_set to copy.
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* @param __a An allocator object.
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*/
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unordered_set(const unordered_set& __uset,
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const allocator_type& __a)
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: _M_h(__uset._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_set to move.
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* @param __a An allocator object.
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*/
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unordered_set(unordered_set&& __uset,
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const allocator_type& __a)
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noexcept( noexcept(_Hashtable(std::move(__uset._M_h), __a)) )
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: _M_h(std::move(__uset._M_h), __a)
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{ }
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/**
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* @brief Builds an %unordered_set 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_set 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_set(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_set(size_type __n, const allocator_type& __a)
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: unordered_set(__n, hasher(), key_equal(), __a)
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{ }
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unordered_set(size_type __n, const hasher& __hf,
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const allocator_type& __a)
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: unordered_set(__n, __hf, key_equal(), __a)
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{ }
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template<typename _InputIterator>
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unordered_set(_InputIterator __first, _InputIterator __last,
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size_type __n,
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const allocator_type& __a)
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: unordered_set(__first, __last, __n, hasher(), key_equal(), __a)
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{ }
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template<typename _InputIterator>
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unordered_set(_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_set(__first, __last, __n, __hf, key_equal(), __a)
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{ }
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unordered_set(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_set(__l, __n, hasher(), key_equal(), __a)
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{ }
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unordered_set(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_set(__l, __n, __hf, key_equal(), __a)
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{ }
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/// Copy assignment operator.
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unordered_set&
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operator=(const unordered_set&) = default;
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/// Move assignment operator.
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unordered_set&
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operator=(unordered_set&&) = default;
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/**
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* @brief %Unordered_set 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_set 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_set and
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* that the resulting %unordered_set's size is the same as the number
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* of elements assigned.
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*/
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unordered_set&
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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 used by the %unordered_set.
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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_set is empty.
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_GLIBCXX_NODISCARD 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_set.
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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_set.
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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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/**
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* Returns a read-only (constant) iterator that points to the first
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* element in the %unordered_set.
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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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const_iterator
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begin() const noexcept
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{ return _M_h.begin(); }
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///@}
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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_set.
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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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const_iterator
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end() const 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 to the first
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* element in the %unordered_set.
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*/
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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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* Returns a read-only (constant) iterator that points one past the last
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* element in the %unordered_set.
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*/
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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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// modifiers.
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/**
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* @brief Attempts to build and insert an element into the
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* %unordered_set.
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* @param __args Arguments used to generate an element.
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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 element, and the second is a bool
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* that is true if the element was actually inserted.
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*
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* This function attempts to build and insert an element into the
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* %unordered_set. An %unordered_set relies on unique keys and thus an
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* element is only inserted if it is not already present in the
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* %unordered_set.
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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 insert an element into the %unordered_set.
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* @param __pos An iterator that serves as a hint as to where the
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* element should be inserted.
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* @param __args Arguments used to generate the element to be
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* inserted.
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* @return An iterator that points to the element with key equivalent to
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* the one generated from @a __args (may or may not be the
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* element itself).
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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. Note that the first parameter is only a hint and can
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* potentially improve the performance of the insertion process. A bad
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* hint would cause no gains in efficiency.
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*
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* For more on @a hinting, see:
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* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
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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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///@{
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/**
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* @brief Attempts to insert an element into the %unordered_set.
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* @param __x Element to be inserted.
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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 element, and the second is a bool
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* that is true if the element was actually inserted.
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*
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* This function attempts to insert an element into the %unordered_set.
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* An %unordered_set relies on unique keys and thus an element is only
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* inserted if it is not already present in the %unordered_set.
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*
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* Insertion requires amortized constant time.
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*/
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std::pair<iterator, bool>
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insert(const value_type& __x)
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{ return _M_h.insert(__x); }
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std::pair<iterator, bool>
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insert(value_type&& __x)
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{ return _M_h.insert(std::move(__x)); }
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///@}
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///@{
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/**
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* @brief Attempts to insert an element into the %unordered_set.
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* @param __hint An iterator that serves as a hint as to where the
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* element should be inserted.
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* @param __x Element to be inserted.
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* @return An iterator that points to the element with key of
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* @a __x (may or may not be the element passed in).
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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 insert()
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* does. Note that the first parameter is only a hint and can
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* potentially improve the performance of the insertion process. A bad
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* hint would cause no gains in efficiency.
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*
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* For more on @a hinting, see:
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* https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
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*
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* Insertion requires amortized constant.
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*/
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iterator
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insert(const_iterator __hint, const value_type& __x)
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{ return _M_h.insert(__hint, __x); }
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iterator
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insert(const_iterator __hint, value_type&& __x)
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{ return _M_h.insert(__hint, std::move(__x)); }
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///@}
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/**
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* @brief A template function that attempts to insert a range of
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* elements.
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* @param __first Iterator pointing to the start of the range to be
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* inserted.
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* @param __last Iterator pointing to the end of the range.
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*
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* Complexity similar to that of the range constructor.
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*/
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template<typename _InputIterator>
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void
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insert(_InputIterator __first, _InputIterator __last)
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{ _M_h.insert(__first, __last); }
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/**
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* @brief Attempts to insert a list of elements into the %unordered_set.
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* @param __l A std::initializer_list<value_type> of elements
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* to be inserted.
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*
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* Complexity similar to that of the range constructor.
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*/
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void
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insert(initializer_list<value_type> __l)
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{ _M_h.insert(__l); }
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#if __cplusplus > 201402L
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/// Extract a node.
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node_type
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extract(const_iterator __pos)
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{
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__glibcxx_assert(__pos != end());
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return _M_h.extract(__pos);
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}
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/// Extract a node.
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node_type
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extract(const key_type& __key)
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{ return _M_h.extract(__key); }
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/// Re-insert an extracted node.
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insert_return_type
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insert(node_type&& __nh)
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{ return _M_h._M_reinsert_node(std::move(__nh)); }
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/// Re-insert an extracted node.
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iterator
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insert(const_iterator, node_type&& __nh)
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{ return _M_h._M_reinsert_node(std::move(__nh)).position; }
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#endif // C++17
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///@{
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/**
|
|
* @brief Erases an element from an %unordered_set.
|
|
* @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_set. 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_set. For an %unordered_set 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_set.
|
|
* @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_set.
|
|
* 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 __first, const_iterator __last)
|
|
{ return _M_h.erase(__first, __last); }
|
|
|
|
/**
|
|
* Erases all elements in an %unordered_set. 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_set.
|
|
* @param __x An %unordered_set of the same element and allocator
|
|
* types.
|
|
*
|
|
* This exchanges the elements between two sets in constant time.
|
|
* Note that the global std::swap() function is specialized such that
|
|
* std::swap(s1,s2) will feed to this function.
|
|
*/
|
|
void
|
|
swap(unordered_set& __x)
|
|
noexcept( noexcept(_M_h.swap(__x._M_h)) )
|
|
{ _M_h.swap(__x._M_h); }
|
|
|
|
#if __cplusplus > 201402L
|
|
template<typename, typename, typename>
|
|
friend class std::_Hash_merge_helper;
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_set<_Value, _H2, _P2, _Alloc>& __source)
|
|
{
|
|
using _Merge_helper = _Hash_merge_helper<unordered_set, _H2, _P2>;
|
|
_M_h._M_merge_unique(_Merge_helper::_S_get_table(__source));
|
|
}
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_set<_Value, _H2, _P2, _Alloc>&& __source)
|
|
{ merge(__source); }
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_multiset<_Value, _H2, _P2, _Alloc>& __source)
|
|
{
|
|
using _Merge_helper = _Hash_merge_helper<unordered_set, _H2, _P2>;
|
|
_M_h._M_merge_unique(_Merge_helper::_S_get_table(__source));
|
|
}
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_multiset<_Value, _H2, _P2, _Alloc>&& __source)
|
|
{ merge(__source); }
|
|
#endif // C++17
|
|
|
|
// observers.
|
|
|
|
/// Returns the hash functor object with which the %unordered_set was
|
|
/// constructed.
|
|
hasher
|
|
hash_function() const
|
|
{ return _M_h.hash_function(); }
|
|
|
|
/// Returns the key comparison object with which the %unordered_set was
|
|
/// constructed.
|
|
key_equal
|
|
key_eq() const
|
|
{ return _M_h.key_eq(); }
|
|
|
|
// lookup.
|
|
|
|
///@{
|
|
/**
|
|
* @brief Tries to locate an element in an %unordered_set.
|
|
* @param __x Element 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); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
find(const _Kt& __k)
|
|
-> decltype(_M_h._M_find_tr(__k))
|
|
{ return _M_h._M_find_tr(__k); }
|
|
#endif
|
|
|
|
const_iterator
|
|
find(const key_type& __x) const
|
|
{ return _M_h.find(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
find(const _Kt& __k) const
|
|
-> decltype(_M_h._M_find_tr(__k))
|
|
{ return _M_h._M_find_tr(__k); }
|
|
#endif
|
|
///@}
|
|
|
|
///@{
|
|
/**
|
|
* @brief Finds the number of elements.
|
|
* @param __x Element to located.
|
|
* @return Number of elements with specified key.
|
|
*
|
|
* This function only makes sense for unordered_multisets; for
|
|
* unordered_set the result will either be 0 (not present) or 1
|
|
* (present).
|
|
*/
|
|
size_type
|
|
count(const key_type& __x) const
|
|
{ return _M_h.count(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
count(const _Kt& __k) const
|
|
-> decltype(_M_h._M_count_tr(__k))
|
|
{ return _M_h._M_count_tr(__k); }
|
|
#endif
|
|
///@}
|
|
|
|
#if __cplusplus > 201703L
|
|
///@{
|
|
/**
|
|
* @brief Finds whether an element with the given key exists.
|
|
* @param __x Key of elements to be located.
|
|
* @return True if there is any element with the specified key.
|
|
*/
|
|
bool
|
|
contains(const key_type& __x) const
|
|
{ return _M_h.find(__x) != _M_h.end(); }
|
|
|
|
template<typename _Kt>
|
|
auto
|
|
contains(const _Kt& __k) const
|
|
-> decltype(_M_h._M_find_tr(__k), void(), true)
|
|
{ return _M_h._M_find_tr(__k) != _M_h.end(); }
|
|
///@}
|
|
#endif
|
|
|
|
///@{
|
|
/**
|
|
* @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 multisets.
|
|
*/
|
|
std::pair<iterator, iterator>
|
|
equal_range(const key_type& __x)
|
|
{ return _M_h.equal_range(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
equal_range(const _Kt& __k)
|
|
-> decltype(_M_h._M_equal_range_tr(__k))
|
|
{ return _M_h._M_equal_range_tr(__k); }
|
|
#endif
|
|
|
|
std::pair<const_iterator, const_iterator>
|
|
equal_range(const key_type& __x) const
|
|
{ return _M_h.equal_range(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
equal_range(const _Kt& __k) const
|
|
-> decltype(_M_h._M_equal_range_tr(__k))
|
|
{ return _M_h._M_equal_range_tr(__k); }
|
|
#endif
|
|
///@}
|
|
|
|
// bucket interface.
|
|
|
|
/// Returns the number of buckets of the %unordered_set.
|
|
size_type
|
|
bucket_count() const noexcept
|
|
{ return _M_h.bucket_count(); }
|
|
|
|
/// Returns the maximum number of buckets of the %unordered_set.
|
|
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-only (constant) iterator pointing to the first
|
|
* bucket element.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
local_iterator
|
|
begin(size_type __n)
|
|
{ return _M_h.begin(__n); }
|
|
|
|
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-only (constant) iterator pointing to one past
|
|
* the last bucket elements.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
local_iterator
|
|
end(size_type __n)
|
|
{ return _M_h.end(__n); }
|
|
|
|
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_set 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_set 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_set.
|
|
* @param __n The new number of buckets.
|
|
*
|
|
* Rehash will occur only if the new number of buckets respect the
|
|
* %unordered_set maximum load factor.
|
|
*/
|
|
void
|
|
rehash(size_type __n)
|
|
{ _M_h.rehash(__n); }
|
|
|
|
/**
|
|
* @brief Prepare the %unordered_set 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 _Value1, typename _Hash1, typename _Pred1,
|
|
typename _Alloc1>
|
|
friend bool
|
|
operator==(const unordered_set<_Value1, _Hash1, _Pred1, _Alloc1>&,
|
|
const unordered_set<_Value1, _Hash1, _Pred1, _Alloc1>&);
|
|
};
|
|
|
|
#if __cpp_deduction_guides >= 201606
|
|
|
|
template<typename _InputIterator,
|
|
typename _Hash =
|
|
hash<typename iterator_traits<_InputIterator>::value_type>,
|
|
typename _Pred =
|
|
equal_to<typename iterator_traits<_InputIterator>::value_type>,
|
|
typename _Allocator =
|
|
allocator<typename iterator_traits<_InputIterator>::value_type>,
|
|
typename = _RequireInputIter<_InputIterator>,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireNotAllocator<_Pred>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_set(_InputIterator, _InputIterator,
|
|
unordered_set<int>::size_type = {},
|
|
_Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
|
|
-> unordered_set<typename iterator_traits<_InputIterator>::value_type,
|
|
_Hash, _Pred, _Allocator>;
|
|
|
|
template<typename _Tp, typename _Hash = hash<_Tp>,
|
|
typename _Pred = equal_to<_Tp>,
|
|
typename _Allocator = allocator<_Tp>,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireNotAllocator<_Pred>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_set(initializer_list<_Tp>,
|
|
unordered_set<int>::size_type = {},
|
|
_Hash = _Hash(), _Pred = _Pred(), _Allocator = _Allocator())
|
|
-> unordered_set<_Tp, _Hash, _Pred, _Allocator>;
|
|
|
|
template<typename _InputIterator, typename _Allocator,
|
|
typename = _RequireInputIter<_InputIterator>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_set(_InputIterator, _InputIterator,
|
|
unordered_set<int>::size_type, _Allocator)
|
|
-> unordered_set<typename iterator_traits<_InputIterator>::value_type,
|
|
hash<
|
|
typename iterator_traits<_InputIterator>::value_type>,
|
|
equal_to<
|
|
typename iterator_traits<_InputIterator>::value_type>,
|
|
_Allocator>;
|
|
|
|
template<typename _InputIterator, typename _Hash, typename _Allocator,
|
|
typename = _RequireInputIter<_InputIterator>,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_set(_InputIterator, _InputIterator,
|
|
unordered_set<int>::size_type,
|
|
_Hash, _Allocator)
|
|
-> unordered_set<typename iterator_traits<_InputIterator>::value_type,
|
|
_Hash,
|
|
equal_to<
|
|
typename iterator_traits<_InputIterator>::value_type>,
|
|
_Allocator>;
|
|
|
|
template<typename _Tp, typename _Allocator,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_set(initializer_list<_Tp>,
|
|
unordered_set<int>::size_type, _Allocator)
|
|
-> unordered_set<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
|
|
|
|
template<typename _Tp, typename _Hash, typename _Allocator,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_set(initializer_list<_Tp>,
|
|
unordered_set<int>::size_type, _Hash, _Allocator)
|
|
-> unordered_set<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
|
|
|
|
#endif
|
|
|
|
/**
|
|
* @brief A standard container composed of equivalent keys
|
|
* (possibly containing multiple of each key value) in which the
|
|
* elements' keys are the elements themselves.
|
|
*
|
|
* @ingroup unordered_associative_containers
|
|
*
|
|
* @tparam _Value Type of key 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 allocator<_Key>.
|
|
*
|
|
* Meets the requirements of a <a href="tables.html#65">container</a>, and
|
|
* <a href="tables.html#xx">unordered associative container</a>
|
|
*
|
|
* Base is _Hashtable, dispatched at compile time via template
|
|
* alias __umset_hashtable.
|
|
*/
|
|
template<typename _Value,
|
|
typename _Hash = hash<_Value>,
|
|
typename _Pred = equal_to<_Value>,
|
|
typename _Alloc = allocator<_Value>>
|
|
class unordered_multiset
|
|
{
|
|
typedef __umset_hashtable<_Value, _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::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;
|
|
///@}
|
|
|
|
#if __cplusplus > 201402L
|
|
using node_type = typename _Hashtable::node_type;
|
|
#endif
|
|
|
|
// construct/destroy/copy
|
|
|
|
/// Default constructor.
|
|
unordered_multiset() = default;
|
|
|
|
/**
|
|
* @brief Default constructor creates no elements.
|
|
* @param __n Minimal initial number of buckets.
|
|
* @param __hf A hash functor.
|
|
* @param __eql A key equality functor.
|
|
* @param __a An allocator object.
|
|
*/
|
|
explicit
|
|
unordered_multiset(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_multiset 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_multiset consisting of copies of the elements
|
|
* from [__first,__last). This is linear in N (where N is
|
|
* distance(__first,__last)).
|
|
*/
|
|
template<typename _InputIterator>
|
|
unordered_multiset(_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_multiset(const unordered_multiset&) = default;
|
|
|
|
/// Move constructor.
|
|
unordered_multiset(unordered_multiset&&) = default;
|
|
|
|
/**
|
|
* @brief Builds an %unordered_multiset 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_multiset consisting of copies of the elements in
|
|
* the list. This is linear in N (where N is @a __l.size()).
|
|
*/
|
|
unordered_multiset(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)
|
|
{ }
|
|
|
|
/// Copy assignment operator.
|
|
unordered_multiset&
|
|
operator=(const unordered_multiset&) = default;
|
|
|
|
/// Move assignment operator.
|
|
unordered_multiset&
|
|
operator=(unordered_multiset&&) = default;
|
|
|
|
/**
|
|
* @brief Creates an %unordered_multiset with no elements.
|
|
* @param __a An allocator object.
|
|
*/
|
|
explicit
|
|
unordered_multiset(const allocator_type& __a)
|
|
: _M_h(__a)
|
|
{ }
|
|
|
|
/*
|
|
* @brief Copy constructor with allocator argument.
|
|
* @param __uset Input %unordered_multiset to copy.
|
|
* @param __a An allocator object.
|
|
*/
|
|
unordered_multiset(const unordered_multiset& __umset,
|
|
const allocator_type& __a)
|
|
: _M_h(__umset._M_h, __a)
|
|
{ }
|
|
|
|
/*
|
|
* @brief Move constructor with allocator argument.
|
|
* @param __umset Input %unordered_multiset to move.
|
|
* @param __a An allocator object.
|
|
*/
|
|
unordered_multiset(unordered_multiset&& __umset,
|
|
const allocator_type& __a)
|
|
noexcept( noexcept(_Hashtable(std::move(__umset._M_h), __a)) )
|
|
: _M_h(std::move(__umset._M_h), __a)
|
|
{ }
|
|
|
|
unordered_multiset(size_type __n, const allocator_type& __a)
|
|
: unordered_multiset(__n, hasher(), key_equal(), __a)
|
|
{ }
|
|
|
|
unordered_multiset(size_type __n, const hasher& __hf,
|
|
const allocator_type& __a)
|
|
: unordered_multiset(__n, __hf, key_equal(), __a)
|
|
{ }
|
|
|
|
template<typename _InputIterator>
|
|
unordered_multiset(_InputIterator __first, _InputIterator __last,
|
|
size_type __n,
|
|
const allocator_type& __a)
|
|
: unordered_multiset(__first, __last, __n, hasher(), key_equal(), __a)
|
|
{ }
|
|
|
|
template<typename _InputIterator>
|
|
unordered_multiset(_InputIterator __first, _InputIterator __last,
|
|
size_type __n, const hasher& __hf,
|
|
const allocator_type& __a)
|
|
: unordered_multiset(__first, __last, __n, __hf, key_equal(), __a)
|
|
{ }
|
|
|
|
unordered_multiset(initializer_list<value_type> __l,
|
|
size_type __n,
|
|
const allocator_type& __a)
|
|
: unordered_multiset(__l, __n, hasher(), key_equal(), __a)
|
|
{ }
|
|
|
|
unordered_multiset(initializer_list<value_type> __l,
|
|
size_type __n, const hasher& __hf,
|
|
const allocator_type& __a)
|
|
: unordered_multiset(__l, __n, __hf, key_equal(), __a)
|
|
{ }
|
|
|
|
/**
|
|
* @brief %Unordered_multiset list assignment operator.
|
|
* @param __l An initializer_list.
|
|
*
|
|
* This function fills an %unordered_multiset with copies of the elements
|
|
* in the initializer list @a __l.
|
|
*
|
|
* Note that the assignment completely changes the %unordered_multiset
|
|
* and that the resulting %unordered_multiset's size is the same as the
|
|
* number of elements assigned.
|
|
*/
|
|
unordered_multiset&
|
|
operator=(initializer_list<value_type> __l)
|
|
{
|
|
_M_h = __l;
|
|
return *this;
|
|
}
|
|
|
|
/// Returns the allocator object used by the %unordered_multiset.
|
|
allocator_type
|
|
get_allocator() const noexcept
|
|
{ return _M_h.get_allocator(); }
|
|
|
|
// size and capacity:
|
|
|
|
/// Returns true if the %unordered_multiset is empty.
|
|
_GLIBCXX_NODISCARD bool
|
|
empty() const noexcept
|
|
{ return _M_h.empty(); }
|
|
|
|
/// Returns the size of the %unordered_multiset.
|
|
size_type
|
|
size() const noexcept
|
|
{ return _M_h.size(); }
|
|
|
|
/// Returns the maximum size of the %unordered_multiset.
|
|
size_type
|
|
max_size() const noexcept
|
|
{ return _M_h.max_size(); }
|
|
|
|
// iterators.
|
|
|
|
///@{
|
|
/**
|
|
* Returns a read-only (constant) iterator that points to the first
|
|
* element in the %unordered_multiset.
|
|
*/
|
|
iterator
|
|
begin() noexcept
|
|
{ return _M_h.begin(); }
|
|
|
|
const_iterator
|
|
begin() const noexcept
|
|
{ return _M_h.begin(); }
|
|
///@}
|
|
|
|
///@{
|
|
/**
|
|
* Returns a read-only (constant) iterator that points one past the last
|
|
* element in the %unordered_multiset.
|
|
*/
|
|
iterator
|
|
end() noexcept
|
|
{ return _M_h.end(); }
|
|
|
|
const_iterator
|
|
end() const noexcept
|
|
{ return _M_h.end(); }
|
|
///@}
|
|
|
|
/**
|
|
* Returns a read-only (constant) iterator that points to the first
|
|
* element in the %unordered_multiset.
|
|
*/
|
|
const_iterator
|
|
cbegin() const noexcept
|
|
{ return _M_h.begin(); }
|
|
|
|
/**
|
|
* Returns a read-only (constant) iterator that points one past the last
|
|
* element in the %unordered_multiset.
|
|
*/
|
|
const_iterator
|
|
cend() const noexcept
|
|
{ return _M_h.end(); }
|
|
|
|
// modifiers.
|
|
|
|
/**
|
|
* @brief Builds and insert an element into the %unordered_multiset.
|
|
* @param __args Arguments used to generate an element.
|
|
* @return An iterator that points to the inserted element.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
template<typename... _Args>
|
|
iterator
|
|
emplace(_Args&&... __args)
|
|
{ return _M_h.emplace(std::forward<_Args>(__args)...); }
|
|
|
|
/**
|
|
* @brief Inserts an element into the %unordered_multiset.
|
|
* @param __pos An iterator that serves as a hint as to where the
|
|
* element should be inserted.
|
|
* @param __args Arguments used to generate the element to be
|
|
* inserted.
|
|
* @return An iterator that points to the inserted element.
|
|
*
|
|
* 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 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 an element into the %unordered_multiset.
|
|
* @param __x Element to be inserted.
|
|
* @return An iterator that points to the inserted element.
|
|
*
|
|
* Insertion requires amortized constant time.
|
|
*/
|
|
iterator
|
|
insert(const value_type& __x)
|
|
{ return _M_h.insert(__x); }
|
|
|
|
iterator
|
|
insert(value_type&& __x)
|
|
{ return _M_h.insert(std::move(__x)); }
|
|
///@}
|
|
|
|
///@{
|
|
/**
|
|
* @brief Inserts an element into the %unordered_multiset.
|
|
* @param __hint An iterator that serves as a hint as to where the
|
|
* element should be inserted.
|
|
* @param __x Element to be inserted.
|
|
* @return An iterator that points to the inserted element.
|
|
*
|
|
* 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 amortized constant.
|
|
*/
|
|
iterator
|
|
insert(const_iterator __hint, const value_type& __x)
|
|
{ return _M_h.insert(__hint, __x); }
|
|
|
|
iterator
|
|
insert(const_iterator __hint, value_type&& __x)
|
|
{ return _M_h.insert(__hint, std::move(__x)); }
|
|
///@}
|
|
|
|
/**
|
|
* @brief A template function that inserts 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 Inserts a list of elements into the %unordered_multiset.
|
|
* @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
|
|
/// Extract a node.
|
|
node_type
|
|
extract(const_iterator __pos)
|
|
{
|
|
__glibcxx_assert(__pos != end());
|
|
return _M_h.extract(__pos);
|
|
}
|
|
|
|
/// Extract a node.
|
|
node_type
|
|
extract(const key_type& __key)
|
|
{ return _M_h.extract(__key); }
|
|
|
|
/// Re-insert an extracted node.
|
|
iterator
|
|
insert(node_type&& __nh)
|
|
{ return _M_h._M_reinsert_node_multi(cend(), std::move(__nh)); }
|
|
|
|
/// Re-insert an extracted node.
|
|
iterator
|
|
insert(const_iterator __hint, node_type&& __nh)
|
|
{ return _M_h._M_reinsert_node_multi(__hint, std::move(__nh)); }
|
|
#endif // C++17
|
|
|
|
///@{
|
|
/**
|
|
* @brief Erases an element from an %unordered_multiset.
|
|
* @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_multiset.
|
|
*
|
|
* 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_multiset.
|
|
*
|
|
* 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_multiset.
|
|
* @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_multiset.
|
|
*
|
|
* 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 __first, const_iterator __last)
|
|
{ return _M_h.erase(__first, __last); }
|
|
|
|
/**
|
|
* Erases all elements in an %unordered_multiset.
|
|
*
|
|
* 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_multiset.
|
|
* @param __x An %unordered_multiset of the same element and allocator
|
|
* types.
|
|
*
|
|
* This exchanges the elements between two sets in constant time.
|
|
* Note that the global std::swap() function is specialized such that
|
|
* std::swap(s1,s2) will feed to this function.
|
|
*/
|
|
void
|
|
swap(unordered_multiset& __x)
|
|
noexcept( noexcept(_M_h.swap(__x._M_h)) )
|
|
{ _M_h.swap(__x._M_h); }
|
|
|
|
#if __cplusplus > 201402L
|
|
template<typename, typename, typename>
|
|
friend class std::_Hash_merge_helper;
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_multiset<_Value, _H2, _P2, _Alloc>& __source)
|
|
{
|
|
using _Merge_helper
|
|
= _Hash_merge_helper<unordered_multiset, _H2, _P2>;
|
|
_M_h._M_merge_multi(_Merge_helper::_S_get_table(__source));
|
|
}
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_multiset<_Value, _H2, _P2, _Alloc>&& __source)
|
|
{ merge(__source); }
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_set<_Value, _H2, _P2, _Alloc>& __source)
|
|
{
|
|
using _Merge_helper
|
|
= _Hash_merge_helper<unordered_multiset, _H2, _P2>;
|
|
_M_h._M_merge_multi(_Merge_helper::_S_get_table(__source));
|
|
}
|
|
|
|
template<typename _H2, typename _P2>
|
|
void
|
|
merge(unordered_set<_Value, _H2, _P2, _Alloc>&& __source)
|
|
{ merge(__source); }
|
|
#endif // C++17
|
|
|
|
// observers.
|
|
|
|
/// Returns the hash functor object with which the %unordered_multiset
|
|
/// was constructed.
|
|
hasher
|
|
hash_function() const
|
|
{ return _M_h.hash_function(); }
|
|
|
|
/// Returns the key comparison object with which the %unordered_multiset
|
|
/// was constructed.
|
|
key_equal
|
|
key_eq() const
|
|
{ return _M_h.key_eq(); }
|
|
|
|
// lookup.
|
|
|
|
///@{
|
|
/**
|
|
* @brief Tries to locate an element in an %unordered_multiset.
|
|
* @param __x Element 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); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
find(const _Kt& __x)
|
|
-> decltype(_M_h._M_find_tr(__x))
|
|
{ return _M_h._M_find_tr(__x); }
|
|
#endif
|
|
|
|
const_iterator
|
|
find(const key_type& __x) const
|
|
{ return _M_h.find(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
find(const _Kt& __x) const
|
|
-> decltype(_M_h._M_find_tr(__x))
|
|
{ return _M_h._M_find_tr(__x); }
|
|
#endif
|
|
///@}
|
|
|
|
///@{
|
|
/**
|
|
* @brief Finds the number of elements.
|
|
* @param __x Element to located.
|
|
* @return Number of elements with specified key.
|
|
*/
|
|
size_type
|
|
count(const key_type& __x) const
|
|
{ return _M_h.count(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
count(const _Kt& __x) const -> decltype(_M_h._M_count_tr(__x))
|
|
{ return _M_h._M_count_tr(__x); }
|
|
#endif
|
|
///@}
|
|
|
|
#if __cplusplus > 201703L
|
|
///@{
|
|
/**
|
|
* @brief Finds whether an element with the given key exists.
|
|
* @param __x Key of elements to be located.
|
|
* @return True if there is any element with the specified key.
|
|
*/
|
|
bool
|
|
contains(const key_type& __x) const
|
|
{ return _M_h.find(__x) != _M_h.end(); }
|
|
|
|
template<typename _Kt>
|
|
auto
|
|
contains(const _Kt& __x) const
|
|
-> decltype(_M_h._M_find_tr(__x), void(), true)
|
|
{ return _M_h._M_find_tr(__x) != _M_h.end(); }
|
|
///@}
|
|
#endif
|
|
|
|
///@{
|
|
/**
|
|
* @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); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
equal_range(const _Kt& __x)
|
|
-> decltype(_M_h._M_equal_range_tr(__x))
|
|
{ return _M_h._M_equal_range_tr(__x); }
|
|
#endif
|
|
|
|
std::pair<const_iterator, const_iterator>
|
|
equal_range(const key_type& __x) const
|
|
{ return _M_h.equal_range(__x); }
|
|
|
|
#if __cplusplus > 201703L
|
|
template<typename _Kt>
|
|
auto
|
|
equal_range(const _Kt& __x) const
|
|
-> decltype(_M_h._M_equal_range_tr(__x))
|
|
{ return _M_h._M_equal_range_tr(__x); }
|
|
#endif
|
|
///@}
|
|
|
|
// bucket interface.
|
|
|
|
/// Returns the number of buckets of the %unordered_multiset.
|
|
size_type
|
|
bucket_count() const noexcept
|
|
{ return _M_h.bucket_count(); }
|
|
|
|
/// Returns the maximum number of buckets of the %unordered_multiset.
|
|
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-only (constant) iterator pointing to the first
|
|
* bucket element.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
local_iterator
|
|
begin(size_type __n)
|
|
{ return _M_h.begin(__n); }
|
|
|
|
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-only (constant) iterator pointing to one past
|
|
* the last bucket elements.
|
|
* @param __n The bucket index.
|
|
* @return A read-only local iterator.
|
|
*/
|
|
local_iterator
|
|
end(size_type __n)
|
|
{ return _M_h.end(__n); }
|
|
|
|
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_multiset 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_multiset 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_multiset.
|
|
* @param __n The new number of buckets.
|
|
*
|
|
* Rehash will occur only if the new number of buckets respect the
|
|
* %unordered_multiset maximum load factor.
|
|
*/
|
|
void
|
|
rehash(size_type __n)
|
|
{ _M_h.rehash(__n); }
|
|
|
|
/**
|
|
* @brief Prepare the %unordered_multiset 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 _Value1, typename _Hash1, typename _Pred1,
|
|
typename _Alloc1>
|
|
friend bool
|
|
operator==(const unordered_multiset<_Value1, _Hash1, _Pred1, _Alloc1>&,
|
|
const unordered_multiset<_Value1, _Hash1, _Pred1, _Alloc1>&);
|
|
};
|
|
|
|
|
|
#if __cpp_deduction_guides >= 201606
|
|
|
|
template<typename _InputIterator,
|
|
typename _Hash =
|
|
hash<typename iterator_traits<_InputIterator>::value_type>,
|
|
typename _Pred =
|
|
equal_to<typename iterator_traits<_InputIterator>::value_type>,
|
|
typename _Allocator =
|
|
allocator<typename iterator_traits<_InputIterator>::value_type>,
|
|
typename = _RequireInputIter<_InputIterator>,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireNotAllocator<_Pred>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_multiset(_InputIterator, _InputIterator,
|
|
unordered_multiset<int>::size_type = {},
|
|
_Hash = _Hash(), _Pred = _Pred(),
|
|
_Allocator = _Allocator())
|
|
-> unordered_multiset<typename iterator_traits<_InputIterator>::value_type,
|
|
_Hash, _Pred, _Allocator>;
|
|
|
|
template<typename _Tp, typename _Hash = hash<_Tp>,
|
|
typename _Pred = equal_to<_Tp>,
|
|
typename _Allocator = allocator<_Tp>,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireNotAllocator<_Pred>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_multiset(initializer_list<_Tp>,
|
|
unordered_multiset<int>::size_type = {},
|
|
_Hash = _Hash(), _Pred = _Pred(),
|
|
_Allocator = _Allocator())
|
|
-> unordered_multiset<_Tp, _Hash, _Pred, _Allocator>;
|
|
|
|
template<typename _InputIterator, typename _Allocator,
|
|
typename = _RequireInputIter<_InputIterator>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_multiset(_InputIterator, _InputIterator,
|
|
unordered_multiset<int>::size_type, _Allocator)
|
|
-> unordered_multiset<typename iterator_traits<_InputIterator>::value_type,
|
|
hash<typename
|
|
iterator_traits<_InputIterator>::value_type>,
|
|
equal_to<typename
|
|
iterator_traits<_InputIterator>::value_type>,
|
|
_Allocator>;
|
|
|
|
template<typename _InputIterator, typename _Hash, typename _Allocator,
|
|
typename = _RequireInputIter<_InputIterator>,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_multiset(_InputIterator, _InputIterator,
|
|
unordered_multiset<int>::size_type,
|
|
_Hash, _Allocator)
|
|
-> unordered_multiset<typename
|
|
iterator_traits<_InputIterator>::value_type,
|
|
_Hash,
|
|
equal_to<
|
|
typename
|
|
iterator_traits<_InputIterator>::value_type>,
|
|
_Allocator>;
|
|
|
|
template<typename _Tp, typename _Allocator,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_multiset(initializer_list<_Tp>,
|
|
unordered_multiset<int>::size_type, _Allocator)
|
|
-> unordered_multiset<_Tp, hash<_Tp>, equal_to<_Tp>, _Allocator>;
|
|
|
|
template<typename _Tp, typename _Hash, typename _Allocator,
|
|
typename = _RequireNotAllocatorOrIntegral<_Hash>,
|
|
typename = _RequireAllocator<_Allocator>>
|
|
unordered_multiset(initializer_list<_Tp>,
|
|
unordered_multiset<int>::size_type, _Hash, _Allocator)
|
|
-> unordered_multiset<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
|
|
|
|
#endif
|
|
|
|
template<class _Value, class _Hash, class _Pred, class _Alloc>
|
|
inline void
|
|
swap(unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
|
|
unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
|
|
noexcept(noexcept(__x.swap(__y)))
|
|
{ __x.swap(__y); }
|
|
|
|
template<class _Value, class _Hash, class _Pred, class _Alloc>
|
|
inline void
|
|
swap(unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
|
|
unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
|
|
noexcept(noexcept(__x.swap(__y)))
|
|
{ __x.swap(__y); }
|
|
|
|
template<class _Value, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator==(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
|
|
{ return __x._M_h._M_equal(__y._M_h); }
|
|
|
|
#if __cpp_impl_three_way_comparison < 201907L
|
|
template<class _Value, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator!=(const unordered_set<_Value, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_set<_Value, _Hash, _Pred, _Alloc>& __y)
|
|
{ return !(__x == __y); }
|
|
#endif
|
|
|
|
template<class _Value, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator==(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
|
|
{ return __x._M_h._M_equal(__y._M_h); }
|
|
|
|
#if __cpp_impl_three_way_comparison < 201907L
|
|
template<class _Value, class _Hash, class _Pred, class _Alloc>
|
|
inline bool
|
|
operator!=(const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
|
|
const unordered_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
|
|
{ return !(__x == __y); }
|
|
#endif
|
|
|
|
_GLIBCXX_END_NAMESPACE_CONTAINER
|
|
|
|
#if __cplusplus > 201402L
|
|
// Allow std::unordered_set access to internals of compatible sets.
|
|
template<typename _Val, typename _Hash1, typename _Eq1, typename _Alloc,
|
|
typename _Hash2, typename _Eq2>
|
|
struct _Hash_merge_helper<
|
|
_GLIBCXX_STD_C::unordered_set<_Val, _Hash1, _Eq1, _Alloc>, _Hash2, _Eq2>
|
|
{
|
|
private:
|
|
template<typename... _Tp>
|
|
using unordered_set = _GLIBCXX_STD_C::unordered_set<_Tp...>;
|
|
template<typename... _Tp>
|
|
using unordered_multiset = _GLIBCXX_STD_C::unordered_multiset<_Tp...>;
|
|
|
|
friend unordered_set<_Val, _Hash1, _Eq1, _Alloc>;
|
|
|
|
static auto&
|
|
_S_get_table(unordered_set<_Val, _Hash2, _Eq2, _Alloc>& __set)
|
|
{ return __set._M_h; }
|
|
|
|
static auto&
|
|
_S_get_table(unordered_multiset<_Val, _Hash2, _Eq2, _Alloc>& __set)
|
|
{ return __set._M_h; }
|
|
};
|
|
|
|
// Allow std::unordered_multiset access to internals of compatible sets.
|
|
template<typename _Val, typename _Hash1, typename _Eq1, typename _Alloc,
|
|
typename _Hash2, typename _Eq2>
|
|
struct _Hash_merge_helper<
|
|
_GLIBCXX_STD_C::unordered_multiset<_Val, _Hash1, _Eq1, _Alloc>,
|
|
_Hash2, _Eq2>
|
|
{
|
|
private:
|
|
template<typename... _Tp>
|
|
using unordered_set = _GLIBCXX_STD_C::unordered_set<_Tp...>;
|
|
template<typename... _Tp>
|
|
using unordered_multiset = _GLIBCXX_STD_C::unordered_multiset<_Tp...>;
|
|
|
|
friend unordered_multiset<_Val, _Hash1, _Eq1, _Alloc>;
|
|
|
|
static auto&
|
|
_S_get_table(unordered_set<_Val, _Hash2, _Eq2, _Alloc>& __set)
|
|
{ return __set._M_h; }
|
|
|
|
static auto&
|
|
_S_get_table(unordered_multiset<_Val, _Hash2, _Eq2, _Alloc>& __set)
|
|
{ return __set._M_h; }
|
|
};
|
|
#endif // C++17
|
|
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace std
|
|
|
|
#endif /* _UNORDERED_SET_H */
|