85ec4feb11
From-SVN: r256169
683 lines
22 KiB
C++
683 lines
22 KiB
C++
// Queue implementation -*- C++ -*-
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// Copyright (C) 2001-2018 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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/*
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*
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* Copyright (c) 1994
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* Hewlett-Packard Company
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*
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* Permission to use, copy, modify, distribute and sell this software
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* and its documentation for any purpose is hereby granted without fee,
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* provided that the above copyright notice appear in all copies and
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* that both that copyright notice and this permission notice appear
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* in supporting documentation. Hewlett-Packard Company makes no
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* representations about the suitability of this software for any
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* purpose. It is provided "as is" without express or implied warranty.
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*
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*
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* Copyright (c) 1996,1997
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* Silicon Graphics Computer Systems, Inc.
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*
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* Permission to use, copy, modify, distribute and sell this software
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* and its documentation for any purpose is hereby granted without fee,
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* provided that the above copyright notice appear in all copies and
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* that both that copyright notice and this permission notice appear
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* in supporting documentation. Silicon Graphics makes no
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* representations about the suitability of this software for any
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* purpose. It is provided "as is" without express or implied warranty.
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*/
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/** @file bits/stl_queue.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{queue}
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*/
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#ifndef _STL_QUEUE_H
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#define _STL_QUEUE_H 1
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#include <bits/concept_check.h>
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#include <debug/debug.h>
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#if __cplusplus >= 201103L
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# include <bits/uses_allocator.h>
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#endif
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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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/**
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* @brief A standard container giving FIFO behavior.
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*
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* @ingroup sequences
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*
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* @tparam _Tp Type of element.
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* @tparam _Sequence Type of underlying sequence, defaults to deque<_Tp>.
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*
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* Meets many of the requirements of a
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* <a href="tables.html#65">container</a>,
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* but does not define anything to do with iterators. Very few of the
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* other standard container interfaces are defined.
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*
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* This is not a true container, but an @e adaptor. It holds another
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* container, and provides a wrapper interface to that container. The
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* wrapper is what enforces strict first-in-first-out %queue behavior.
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*
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* The second template parameter defines the type of the underlying
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* sequence/container. It defaults to std::deque, but it can be any type
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* that supports @c front, @c back, @c push_back, and @c pop_front,
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* such as std::list or an appropriate user-defined type.
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*
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* Members not found in @a normal containers are @c container_type,
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* which is a typedef for the second Sequence parameter, and @c push and
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* @c pop, which are standard %queue/FIFO operations.
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*/
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template<typename _Tp, typename _Sequence = deque<_Tp> >
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class queue
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{
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#ifdef _GLIBCXX_CONCEPT_CHECKS
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// concept requirements
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typedef typename _Sequence::value_type _Sequence_value_type;
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# if __cplusplus < 201103L
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__glibcxx_class_requires(_Tp, _SGIAssignableConcept)
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# endif
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__glibcxx_class_requires(_Sequence, _FrontInsertionSequenceConcept)
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__glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
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__glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
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#endif
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template<typename _Tp1, typename _Seq1>
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friend bool
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operator==(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
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template<typename _Tp1, typename _Seq1>
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friend bool
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operator<(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
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#if __cplusplus >= 201103L
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template<typename _Alloc>
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using _Uses = typename
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enable_if<uses_allocator<_Sequence, _Alloc>::value>::type;
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#endif
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public:
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typedef typename _Sequence::value_type value_type;
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typedef typename _Sequence::reference reference;
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typedef typename _Sequence::const_reference const_reference;
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typedef typename _Sequence::size_type size_type;
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typedef _Sequence container_type;
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protected:
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/* Maintainers wondering why this isn't uglified as per style
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* guidelines should note that this name is specified in the standard,
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* C++98 [23.2.3.1].
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* (Why? Presumably for the same reason that it's protected instead
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* of private: to allow derivation. But none of the other
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* containers allow for derivation. Odd.)
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*/
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/// @c c is the underlying container.
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_Sequence c;
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public:
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/**
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* @brief Default constructor creates no elements.
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*/
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#if __cplusplus < 201103L
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explicit
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queue(const _Sequence& __c = _Sequence())
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: c(__c) { }
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#else
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template<typename _Seq = _Sequence, typename _Requires = typename
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enable_if<is_default_constructible<_Seq>::value>::type>
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queue()
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: c() { }
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explicit
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queue(const _Sequence& __c)
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: c(__c) { }
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explicit
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queue(_Sequence&& __c)
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: c(std::move(__c)) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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explicit
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queue(const _Alloc& __a)
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: c(__a) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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queue(const _Sequence& __c, const _Alloc& __a)
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: c(__c, __a) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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queue(_Sequence&& __c, const _Alloc& __a)
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: c(std::move(__c), __a) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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queue(const queue& __q, const _Alloc& __a)
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: c(__q.c, __a) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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queue(queue&& __q, const _Alloc& __a)
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: c(std::move(__q.c), __a) { }
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#endif
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/**
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* Returns true if the %queue is empty.
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*/
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bool
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empty() const
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{ return c.empty(); }
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/** Returns the number of elements in the %queue. */
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size_type
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size() const
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{ return c.size(); }
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/**
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* Returns a read/write reference to the data at the first
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* element of the %queue.
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*/
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reference
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front()
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{
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__glibcxx_requires_nonempty();
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return c.front();
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}
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/**
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* Returns a read-only (constant) reference to the data at the first
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* element of the %queue.
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*/
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const_reference
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front() const
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{
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__glibcxx_requires_nonempty();
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return c.front();
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}
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/**
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* Returns a read/write reference to the data at the last
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* element of the %queue.
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*/
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reference
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back()
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{
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__glibcxx_requires_nonempty();
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return c.back();
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}
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/**
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* Returns a read-only (constant) reference to the data at the last
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* element of the %queue.
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*/
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const_reference
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back() const
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{
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__glibcxx_requires_nonempty();
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return c.back();
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}
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/**
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* @brief Add data to the end of the %queue.
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* @param __x Data to be added.
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*
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* This is a typical %queue operation. The function creates an
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* element at the end of the %queue and assigns the given data
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* to it. The time complexity of the operation depends on the
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* underlying sequence.
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*/
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void
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push(const value_type& __x)
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{ c.push_back(__x); }
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#if __cplusplus >= 201103L
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void
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push(value_type&& __x)
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{ c.push_back(std::move(__x)); }
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#if __cplusplus > 201402L
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template<typename... _Args>
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decltype(auto)
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emplace(_Args&&... __args)
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{ return c.emplace_back(std::forward<_Args>(__args)...); }
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#else
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template<typename... _Args>
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void
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emplace(_Args&&... __args)
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{ c.emplace_back(std::forward<_Args>(__args)...); }
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#endif
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#endif
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/**
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* @brief Removes first element.
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*
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* This is a typical %queue operation. It shrinks the %queue by one.
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* The time complexity of the operation depends on the underlying
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* sequence.
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*
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* Note that no data is returned, and if the first element's
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* data is needed, it should be retrieved before pop() is
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* called.
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*/
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void
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pop()
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{
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__glibcxx_requires_nonempty();
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c.pop_front();
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}
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#if __cplusplus >= 201103L
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void
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swap(queue& __q)
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#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
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noexcept(__is_nothrow_swappable<_Sequence>::value)
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#else
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noexcept(__is_nothrow_swappable<_Tp>::value)
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#endif
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{
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using std::swap;
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swap(c, __q.c);
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}
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#endif // __cplusplus >= 201103L
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};
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/**
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* @brief Queue equality comparison.
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* @param __x A %queue.
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* @param __y A %queue of the same type as @a __x.
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* @return True iff the size and elements of the queues are equal.
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*
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* This is an equivalence relation. Complexity and semantics depend on the
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* underlying sequence type, but the expected rules are: this relation is
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* linear in the size of the sequences, and queues are considered equivalent
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* if their sequences compare equal.
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*/
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template<typename _Tp, typename _Seq>
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inline bool
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operator==(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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{ return __x.c == __y.c; }
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/**
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* @brief Queue ordering relation.
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* @param __x A %queue.
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* @param __y A %queue of the same type as @a x.
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* @return True iff @a __x is lexicographically less than @a __y.
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*
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* This is an total ordering relation. Complexity and semantics
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* depend on the underlying sequence type, but the expected rules
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* are: this relation is linear in the size of the sequences, the
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* elements must be comparable with @c <, and
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* std::lexicographical_compare() is usually used to make the
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* determination.
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*/
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template<typename _Tp, typename _Seq>
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inline bool
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operator<(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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{ return __x.c < __y.c; }
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/// Based on operator==
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template<typename _Tp, typename _Seq>
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inline bool
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operator!=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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{ return !(__x == __y); }
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/// Based on operator<
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template<typename _Tp, typename _Seq>
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inline bool
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operator>(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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{ return __y < __x; }
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/// Based on operator<
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template<typename _Tp, typename _Seq>
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inline bool
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operator<=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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{ return !(__y < __x); }
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/// Based on operator<
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template<typename _Tp, typename _Seq>
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inline bool
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operator>=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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{ return !(__x < __y); }
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#if __cplusplus >= 201103L
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template<typename _Tp, typename _Seq>
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inline
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#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
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// Constrained free swap overload, see p0185r1
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typename enable_if<__is_swappable<_Seq>::value>::type
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#else
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void
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#endif
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swap(queue<_Tp, _Seq>& __x, queue<_Tp, _Seq>& __y)
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noexcept(noexcept(__x.swap(__y)))
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{ __x.swap(__y); }
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template<typename _Tp, typename _Seq, typename _Alloc>
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struct uses_allocator<queue<_Tp, _Seq>, _Alloc>
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: public uses_allocator<_Seq, _Alloc>::type { };
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#endif // __cplusplus >= 201103L
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/**
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* @brief A standard container automatically sorting its contents.
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*
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* @ingroup sequences
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*
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* @tparam _Tp Type of element.
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* @tparam _Sequence Type of underlying sequence, defaults to vector<_Tp>.
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* @tparam _Compare Comparison function object type, defaults to
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* less<_Sequence::value_type>.
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*
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* This is not a true container, but an @e adaptor. It holds
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* another container, and provides a wrapper interface to that
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* container. The wrapper is what enforces priority-based sorting
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* and %queue behavior. Very few of the standard container/sequence
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* interface requirements are met (e.g., iterators).
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*
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* The second template parameter defines the type of the underlying
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* sequence/container. It defaults to std::vector, but it can be
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* any type that supports @c front(), @c push_back, @c pop_back,
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* and random-access iterators, such as std::deque or an
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* appropriate user-defined type.
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*
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* The third template parameter supplies the means of making
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* priority comparisons. It defaults to @c less<value_type> but
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* can be anything defining a strict weak ordering.
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*
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* Members not found in @a normal containers are @c container_type,
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* which is a typedef for the second Sequence parameter, and @c
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* push, @c pop, and @c top, which are standard %queue operations.
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*
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* @note No equality/comparison operators are provided for
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* %priority_queue.
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*
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* @note Sorting of the elements takes place as they are added to,
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* and removed from, the %priority_queue using the
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* %priority_queue's member functions. If you access the elements
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* by other means, and change their data such that the sorting
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* order would be different, the %priority_queue will not re-sort
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* the elements for you. (How could it know to do so?)
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*/
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template<typename _Tp, typename _Sequence = vector<_Tp>,
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typename _Compare = less<typename _Sequence::value_type> >
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class priority_queue
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{
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#ifdef _GLIBCXX_CONCEPT_CHECKS
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// concept requirements
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typedef typename _Sequence::value_type _Sequence_value_type;
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# if __cplusplus < 201103L
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__glibcxx_class_requires(_Tp, _SGIAssignableConcept)
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# endif
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__glibcxx_class_requires(_Sequence, _SequenceConcept)
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__glibcxx_class_requires(_Sequence, _RandomAccessContainerConcept)
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__glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
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__glibcxx_class_requires4(_Compare, bool, _Tp, _Tp,
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_BinaryFunctionConcept)
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#endif
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#if __cplusplus >= 201103L
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template<typename _Alloc>
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using _Uses = typename
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enable_if<uses_allocator<_Sequence, _Alloc>::value>::type;
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#endif
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public:
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typedef typename _Sequence::value_type value_type;
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typedef typename _Sequence::reference reference;
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typedef typename _Sequence::const_reference const_reference;
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typedef typename _Sequence::size_type size_type;
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typedef _Sequence container_type;
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// _GLIBCXX_RESOLVE_LIB_DEFECTS
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// DR 2684. priority_queue lacking comparator typedef
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typedef _Compare value_compare;
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protected:
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// See queue::c for notes on these names.
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_Sequence c;
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_Compare comp;
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public:
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/**
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* @brief Default constructor creates no elements.
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*/
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#if __cplusplus < 201103L
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explicit
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priority_queue(const _Compare& __x = _Compare(),
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const _Sequence& __s = _Sequence())
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: c(__s), comp(__x)
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{ std::make_heap(c.begin(), c.end(), comp); }
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#else
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template<typename _Seq = _Sequence, typename _Requires = typename
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enable_if<__and_<is_default_constructible<_Compare>,
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is_default_constructible<_Seq>>::value>::type>
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priority_queue()
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: c(), comp() { }
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explicit
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priority_queue(const _Compare& __x, const _Sequence& __s)
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: c(__s), comp(__x)
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{ std::make_heap(c.begin(), c.end(), comp); }
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explicit
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priority_queue(const _Compare& __x, _Sequence&& __s = _Sequence())
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: c(std::move(__s)), comp(__x)
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{ std::make_heap(c.begin(), c.end(), comp); }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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explicit
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priority_queue(const _Alloc& __a)
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: c(__a), comp() { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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priority_queue(const _Compare& __x, const _Alloc& __a)
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: c(__a), comp(__x) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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priority_queue(const _Compare& __x, const _Sequence& __c,
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const _Alloc& __a)
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: c(__c, __a), comp(__x) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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priority_queue(const _Compare& __x, _Sequence&& __c, const _Alloc& __a)
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: c(std::move(__c), __a), comp(__x) { }
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template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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priority_queue(const priority_queue& __q, const _Alloc& __a)
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: c(__q.c, __a), comp(__q.comp) { }
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|
template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
|
priority_queue(priority_queue&& __q, const _Alloc& __a)
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: c(std::move(__q.c), __a), comp(std::move(__q.comp)) { }
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#endif
|
|
|
|
/**
|
|
* @brief Builds a %queue from a range.
|
|
* @param __first An input iterator.
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|
* @param __last An input iterator.
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|
* @param __x A comparison functor describing a strict weak ordering.
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|
* @param __s An initial sequence with which to start.
|
|
*
|
|
* Begins by copying @a __s, inserting a copy of the elements
|
|
* from @a [first,last) into the copy of @a __s, then ordering
|
|
* the copy according to @a __x.
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|
*
|
|
* For more information on function objects, see the
|
|
* documentation on @link functors functor base
|
|
* classes@endlink.
|
|
*/
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|
#if __cplusplus < 201103L
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|
template<typename _InputIterator>
|
|
priority_queue(_InputIterator __first, _InputIterator __last,
|
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const _Compare& __x = _Compare(),
|
|
const _Sequence& __s = _Sequence())
|
|
: c(__s), comp(__x)
|
|
{
|
|
__glibcxx_requires_valid_range(__first, __last);
|
|
c.insert(c.end(), __first, __last);
|
|
std::make_heap(c.begin(), c.end(), comp);
|
|
}
|
|
#else
|
|
template<typename _InputIterator>
|
|
priority_queue(_InputIterator __first, _InputIterator __last,
|
|
const _Compare& __x,
|
|
const _Sequence& __s)
|
|
: c(__s), comp(__x)
|
|
{
|
|
__glibcxx_requires_valid_range(__first, __last);
|
|
c.insert(c.end(), __first, __last);
|
|
std::make_heap(c.begin(), c.end(), comp);
|
|
}
|
|
|
|
template<typename _InputIterator>
|
|
priority_queue(_InputIterator __first, _InputIterator __last,
|
|
const _Compare& __x = _Compare(),
|
|
_Sequence&& __s = _Sequence())
|
|
: c(std::move(__s)), comp(__x)
|
|
{
|
|
__glibcxx_requires_valid_range(__first, __last);
|
|
c.insert(c.end(), __first, __last);
|
|
std::make_heap(c.begin(), c.end(), comp);
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* Returns true if the %queue is empty.
|
|
*/
|
|
bool
|
|
empty() const
|
|
{ return c.empty(); }
|
|
|
|
/** Returns the number of elements in the %queue. */
|
|
size_type
|
|
size() const
|
|
{ return c.size(); }
|
|
|
|
/**
|
|
* Returns a read-only (constant) reference to the data at the first
|
|
* element of the %queue.
|
|
*/
|
|
const_reference
|
|
top() const
|
|
{
|
|
__glibcxx_requires_nonempty();
|
|
return c.front();
|
|
}
|
|
|
|
/**
|
|
* @brief Add data to the %queue.
|
|
* @param __x Data to be added.
|
|
*
|
|
* This is a typical %queue operation.
|
|
* The time complexity of the operation depends on the underlying
|
|
* sequence.
|
|
*/
|
|
void
|
|
push(const value_type& __x)
|
|
{
|
|
c.push_back(__x);
|
|
std::push_heap(c.begin(), c.end(), comp);
|
|
}
|
|
|
|
#if __cplusplus >= 201103L
|
|
void
|
|
push(value_type&& __x)
|
|
{
|
|
c.push_back(std::move(__x));
|
|
std::push_heap(c.begin(), c.end(), comp);
|
|
}
|
|
|
|
template<typename... _Args>
|
|
void
|
|
emplace(_Args&&... __args)
|
|
{
|
|
c.emplace_back(std::forward<_Args>(__args)...);
|
|
std::push_heap(c.begin(), c.end(), comp);
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* @brief Removes first element.
|
|
*
|
|
* This is a typical %queue operation. It shrinks the %queue
|
|
* by one. The time complexity of the operation depends on the
|
|
* underlying sequence.
|
|
*
|
|
* Note that no data is returned, and if the first element's
|
|
* data is needed, it should be retrieved before pop() is
|
|
* called.
|
|
*/
|
|
void
|
|
pop()
|
|
{
|
|
__glibcxx_requires_nonempty();
|
|
std::pop_heap(c.begin(), c.end(), comp);
|
|
c.pop_back();
|
|
}
|
|
|
|
#if __cplusplus >= 201103L
|
|
void
|
|
swap(priority_queue& __pq)
|
|
noexcept(__and_<
|
|
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
|
__is_nothrow_swappable<_Sequence>,
|
|
#else
|
|
__is_nothrow_swappable<_Tp>,
|
|
#endif
|
|
__is_nothrow_swappable<_Compare>
|
|
>::value)
|
|
{
|
|
using std::swap;
|
|
swap(c, __pq.c);
|
|
swap(comp, __pq.comp);
|
|
}
|
|
#endif // __cplusplus >= 201103L
|
|
};
|
|
|
|
// No equality/comparison operators are provided for priority_queue.
|
|
|
|
#if __cplusplus >= 201103L
|
|
template<typename _Tp, typename _Sequence, typename _Compare>
|
|
inline
|
|
#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
|
// Constrained free swap overload, see p0185r1
|
|
typename enable_if<__and_<__is_swappable<_Sequence>,
|
|
__is_swappable<_Compare>>::value>::type
|
|
#else
|
|
void
|
|
#endif
|
|
swap(priority_queue<_Tp, _Sequence, _Compare>& __x,
|
|
priority_queue<_Tp, _Sequence, _Compare>& __y)
|
|
noexcept(noexcept(__x.swap(__y)))
|
|
{ __x.swap(__y); }
|
|
|
|
template<typename _Tp, typename _Sequence, typename _Compare,
|
|
typename _Alloc>
|
|
struct uses_allocator<priority_queue<_Tp, _Sequence, _Compare>, _Alloc>
|
|
: public uses_allocator<_Sequence, _Alloc>::type { };
|
|
#endif // __cplusplus >= 201103L
|
|
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace
|
|
|
|
#endif /* _STL_QUEUE_H */
|