[1166] | 1 | // Queue implementation -*- C++ -*-
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| 2 |
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| 3 | // Copyright (C) 2001-2021 Free Software Foundation, Inc.
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| 4 | //
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| 5 | // This file is part of the GNU ISO C++ Library. This library is free
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| 6 | // software; you can redistribute it and/or modify it under the
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| 7 | // terms of the GNU General Public License as published by the
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| 8 | // Free Software Foundation; either version 3, or (at your option)
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| 9 | // any later version.
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| 10 |
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| 11 | // This library is distributed in the hope that it will be useful,
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| 12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 14 | // GNU General Public License for more details.
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| 15 |
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| 16 | // Under Section 7 of GPL version 3, you are granted additional
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| 17 | // permissions described in the GCC Runtime Library Exception, version
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| 18 | // 3.1, as published by the Free Software Foundation.
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| 19 |
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| 20 | // You should have received a copy of the GNU General Public License and
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| 21 | // a copy of the GCC Runtime Library Exception along with this program;
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| 22 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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| 23 | // <http://www.gnu.org/licenses/>.
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| 24 |
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| 25 | /*
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| 26 | *
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| 27 | * Copyright (c) 1994
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| 28 | * Hewlett-Packard Company
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| 29 | *
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| 30 | * Permission to use, copy, modify, distribute and sell this software
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| 31 | * and its documentation for any purpose is hereby granted without fee,
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| 32 | * provided that the above copyright notice appear in all copies and
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| 33 | * that both that copyright notice and this permission notice appear
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| 34 | * in supporting documentation. Hewlett-Packard Company makes no
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| 35 | * representations about the suitability of this software for any
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| 36 | * purpose. It is provided "as is" without express or implied warranty.
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| 37 | *
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| 38 | *
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| 39 | * Copyright (c) 1996,1997
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| 40 | * Silicon Graphics Computer Systems, Inc.
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| 41 | *
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| 42 | * Permission to use, copy, modify, distribute and sell this software
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| 43 | * and its documentation for any purpose is hereby granted without fee,
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| 44 | * provided that the above copyright notice appear in all copies and
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| 45 | * that both that copyright notice and this permission notice appear
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| 46 | * in supporting documentation. Silicon Graphics makes no
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| 47 | * representations about the suitability of this software for any
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| 48 | * purpose. It is provided "as is" without express or implied warranty.
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| 49 | */
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| 50 |
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| 51 | /** @file bits/stl_queue.h
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| 52 | * This is an internal header file, included by other library headers.
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| 53 | * Do not attempt to use it directly. @headername{queue}
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| 54 | */
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| 55 |
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| 56 | #ifndef _STL_QUEUE_H
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| 57 | #define _STL_QUEUE_H 1
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| 58 |
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| 59 | #include <bits/concept_check.h>
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| 60 | #include <debug/debug.h>
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| 61 | #if __cplusplus >= 201103L
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| 62 | # include <bits/uses_allocator.h>
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| 63 | #endif
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| 64 |
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| 65 | namespace std _GLIBCXX_VISIBILITY(default)
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| 66 | {
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| 67 | _GLIBCXX_BEGIN_NAMESPACE_VERSION
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| 68 |
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| 69 | /**
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| 70 | * @brief A standard container giving FIFO behavior.
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| 71 | *
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| 72 | * @ingroup sequences
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| 73 | *
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| 74 | * @tparam _Tp Type of element.
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| 75 | * @tparam _Sequence Type of underlying sequence, defaults to deque<_Tp>.
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| 76 | *
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| 77 | * Meets many of the requirements of a
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| 78 | * <a href="tables.html#65">container</a>,
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| 79 | * but does not define anything to do with iterators. Very few of the
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| 80 | * other standard container interfaces are defined.
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| 81 | *
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| 82 | * This is not a true container, but an @e adaptor. It holds another
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| 83 | * container, and provides a wrapper interface to that container. The
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| 84 | * wrapper is what enforces strict first-in-first-out %queue behavior.
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| 85 | *
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| 86 | * The second template parameter defines the type of the underlying
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| 87 | * sequence/container. It defaults to std::deque, but it can be any type
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| 88 | * that supports @c front, @c back, @c push_back, and @c pop_front,
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| 89 | * such as std::list or an appropriate user-defined type.
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| 90 | *
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| 91 | * Members not found in @a normal containers are @c container_type,
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| 92 | * which is a typedef for the second Sequence parameter, and @c push and
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| 93 | * @c pop, which are standard %queue/FIFO operations.
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| 94 | */
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| 95 | template<typename _Tp, typename _Sequence = deque<_Tp> >
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| 96 | class queue
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| 97 | {
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| 98 | #ifdef _GLIBCXX_CONCEPT_CHECKS
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| 99 | // concept requirements
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| 100 | typedef typename _Sequence::value_type _Sequence_value_type;
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| 101 | # if __cplusplus < 201103L
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| 102 | __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
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| 103 | # endif
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| 104 | __glibcxx_class_requires(_Sequence, _FrontInsertionSequenceConcept)
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| 105 | __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
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| 106 | __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
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| 107 | #endif
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| 108 |
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| 109 | template<typename _Tp1, typename _Seq1>
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| 110 | friend bool
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| 111 | operator==(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
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| 112 |
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| 113 | template<typename _Tp1, typename _Seq1>
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| 114 | friend bool
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| 115 | operator<(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
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| 116 |
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| 117 | #if __cpp_lib_three_way_comparison
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| 118 | template<typename _Tp1, three_way_comparable _Seq1>
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| 119 | friend compare_three_way_result_t<_Seq1>
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| 120 | operator<=>(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
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| 121 | #endif
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| 122 |
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| 123 | #if __cplusplus >= 201103L
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| 124 | template<typename _Alloc>
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| 125 | using _Uses = typename
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| 126 | enable_if<uses_allocator<_Sequence, _Alloc>::value>::type;
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| 127 |
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| 128 | #if __cplusplus >= 201703L
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| 129 | // _GLIBCXX_RESOLVE_LIB_DEFECTS
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| 130 | // 2566. Requirements on the first template parameter of container
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| 131 | // adaptors
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| 132 | static_assert(is_same<_Tp, typename _Sequence::value_type>::value,
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| 133 | "value_type must be the same as the underlying container");
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| 134 | #endif // C++17
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| 135 | #endif // C++11
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| 136 |
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| 137 | public:
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| 138 | typedef typename _Sequence::value_type value_type;
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| 139 | typedef typename _Sequence::reference reference;
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| 140 | typedef typename _Sequence::const_reference const_reference;
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| 141 | typedef typename _Sequence::size_type size_type;
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| 142 | typedef _Sequence container_type;
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| 143 |
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| 144 | protected:
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| 145 | /* Maintainers wondering why this isn't uglified as per style
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| 146 | * guidelines should note that this name is specified in the standard,
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| 147 | * C++98 [23.2.3.1].
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| 148 | * (Why? Presumably for the same reason that it's protected instead
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| 149 | * of private: to allow derivation. But none of the other
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| 150 | * containers allow for derivation. Odd.)
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| 151 | */
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| 152 | /// @c c is the underlying container.
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| 153 | _Sequence c;
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| 154 |
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| 155 | public:
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| 156 | /**
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| 157 | * @brief Default constructor creates no elements.
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| 158 | */
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| 159 | #if __cplusplus < 201103L
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| 160 | explicit
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| 161 | queue(const _Sequence& __c = _Sequence())
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| 162 | : c(__c) { }
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| 163 | #else
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| 164 | template<typename _Seq = _Sequence, typename _Requires = typename
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| 165 | enable_if<is_default_constructible<_Seq>::value>::type>
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| 166 | queue()
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| 167 | : c() { }
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| 168 |
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| 169 | explicit
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| 170 | queue(const _Sequence& __c)
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| 171 | : c(__c) { }
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| 172 |
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| 173 | explicit
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| 174 | queue(_Sequence&& __c)
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| 175 | : c(std::move(__c)) { }
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| 176 |
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| 177 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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| 178 | explicit
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| 179 | queue(const _Alloc& __a)
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| 180 | : c(__a) { }
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| 181 |
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| 182 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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| 183 | queue(const _Sequence& __c, const _Alloc& __a)
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| 184 | : c(__c, __a) { }
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| 185 |
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| 186 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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| 187 | queue(_Sequence&& __c, const _Alloc& __a)
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| 188 | : c(std::move(__c), __a) { }
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| 189 |
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| 190 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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| 191 | queue(const queue& __q, const _Alloc& __a)
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| 192 | : c(__q.c, __a) { }
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| 193 |
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| 194 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
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| 195 | queue(queue&& __q, const _Alloc& __a)
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| 196 | : c(std::move(__q.c), __a) { }
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| 197 | #endif
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| 198 |
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| 199 | /**
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| 200 | * Returns true if the %queue is empty.
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| 201 | */
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| 202 | _GLIBCXX_NODISCARD bool
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| 203 | empty() const
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| 204 | { return c.empty(); }
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| 205 |
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| 206 | /** Returns the number of elements in the %queue. */
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| 207 | size_type
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| 208 | size() const
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| 209 | { return c.size(); }
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| 210 |
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| 211 | /**
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| 212 | * Returns a read/write reference to the data at the first
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| 213 | * element of the %queue.
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| 214 | */
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| 215 | reference
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| 216 | front()
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| 217 | {
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| 218 | __glibcxx_requires_nonempty();
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| 219 | return c.front();
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| 220 | }
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| 221 |
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| 222 | /**
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| 223 | * Returns a read-only (constant) reference to the data at the first
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| 224 | * element of the %queue.
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| 225 | */
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| 226 | const_reference
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| 227 | front() const
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| 228 | {
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| 229 | __glibcxx_requires_nonempty();
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| 230 | return c.front();
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| 231 | }
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| 232 |
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| 233 | /**
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| 234 | * Returns a read/write reference to the data at the last
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| 235 | * element of the %queue.
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| 236 | */
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| 237 | reference
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| 238 | back()
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| 239 | {
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| 240 | __glibcxx_requires_nonempty();
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| 241 | return c.back();
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| 242 | }
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| 243 |
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| 244 | /**
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| 245 | * Returns a read-only (constant) reference to the data at the last
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| 246 | * element of the %queue.
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| 247 | */
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| 248 | const_reference
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| 249 | back() const
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| 250 | {
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| 251 | __glibcxx_requires_nonempty();
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| 252 | return c.back();
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| 253 | }
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| 254 |
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| 255 | /**
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| 256 | * @brief Add data to the end of the %queue.
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| 257 | * @param __x Data to be added.
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| 258 | *
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| 259 | * This is a typical %queue operation. The function creates an
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| 260 | * element at the end of the %queue and assigns the given data
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| 261 | * to it. The time complexity of the operation depends on the
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| 262 | * underlying sequence.
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| 263 | */
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| 264 | void
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| 265 | push(const value_type& __x)
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| 266 | { c.push_back(__x); }
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| 267 |
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| 268 | #if __cplusplus >= 201103L
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| 269 | void
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| 270 | push(value_type&& __x)
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| 271 | { c.push_back(std::move(__x)); }
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| 272 |
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| 273 | #if __cplusplus > 201402L
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| 274 | template<typename... _Args>
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| 275 | decltype(auto)
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| 276 | emplace(_Args&&... __args)
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| 277 | { return c.emplace_back(std::forward<_Args>(__args)...); }
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| 278 | #else
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| 279 | template<typename... _Args>
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| 280 | void
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| 281 | emplace(_Args&&... __args)
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| 282 | { c.emplace_back(std::forward<_Args>(__args)...); }
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| 283 | #endif
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| 284 | #endif
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| 285 |
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| 286 | /**
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| 287 | * @brief Removes first element.
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| 288 | *
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| 289 | * This is a typical %queue operation. It shrinks the %queue by one.
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| 290 | * The time complexity of the operation depends on the underlying
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| 291 | * sequence.
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| 292 | *
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| 293 | * Note that no data is returned, and if the first element's
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| 294 | * data is needed, it should be retrieved before pop() is
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| 295 | * called.
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| 296 | */
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| 297 | void
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| 298 | pop()
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| 299 | {
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| 300 | __glibcxx_requires_nonempty();
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| 301 | c.pop_front();
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| 302 | }
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| 303 |
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| 304 | #if __cplusplus >= 201103L
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| 305 | void
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| 306 | swap(queue& __q)
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| 307 | #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
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| 308 | noexcept(__is_nothrow_swappable<_Sequence>::value)
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| 309 | #else
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| 310 | noexcept(__is_nothrow_swappable<_Tp>::value)
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| 311 | #endif
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| 312 | {
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| 313 | using std::swap;
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| 314 | swap(c, __q.c);
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| 315 | }
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| 316 | #endif // __cplusplus >= 201103L
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| 317 | };
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| 318 |
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| 319 | #if __cpp_deduction_guides >= 201606
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| 320 | template<typename _Container,
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| 321 | typename = _RequireNotAllocator<_Container>>
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| 322 | queue(_Container) -> queue<typename _Container::value_type, _Container>;
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| 323 |
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| 324 | template<typename _Container, typename _Allocator,
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| 325 | typename = _RequireNotAllocator<_Container>,
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| 326 | typename = _RequireAllocator<_Allocator>>
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| 327 | queue(_Container, _Allocator)
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| 328 | -> queue<typename _Container::value_type, _Container>;
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| 329 | #endif
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| 330 |
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| 331 | /**
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| 332 | * @brief Queue equality comparison.
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| 333 | * @param __x A %queue.
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| 334 | * @param __y A %queue of the same type as @a __x.
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| 335 | * @return True iff the size and elements of the queues are equal.
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| 336 | *
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| 337 | * This is an equivalence relation. Complexity and semantics depend on the
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| 338 | * underlying sequence type, but the expected rules are: this relation is
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| 339 | * linear in the size of the sequences, and queues are considered equivalent
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| 340 | * if their sequences compare equal.
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| 341 | */
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| 342 | template<typename _Tp, typename _Seq>
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| 343 | inline bool
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| 344 | operator==(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 345 | { return __x.c == __y.c; }
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| 346 |
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| 347 | /**
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| 348 | * @brief Queue ordering relation.
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| 349 | * @param __x A %queue.
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| 350 | * @param __y A %queue of the same type as @a x.
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| 351 | * @return True iff @a __x is lexicographically less than @a __y.
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| 352 | *
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| 353 | * This is an total ordering relation. Complexity and semantics
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| 354 | * depend on the underlying sequence type, but the expected rules
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| 355 | * are: this relation is linear in the size of the sequences, the
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| 356 | * elements must be comparable with @c <, and
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| 357 | * std::lexicographical_compare() is usually used to make the
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| 358 | * determination.
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| 359 | */
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| 360 | template<typename _Tp, typename _Seq>
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| 361 | inline bool
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| 362 | operator<(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 363 | { return __x.c < __y.c; }
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| 364 |
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| 365 | /// Based on operator==
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| 366 | template<typename _Tp, typename _Seq>
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| 367 | inline bool
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| 368 | operator!=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 369 | { return !(__x == __y); }
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| 370 |
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| 371 | /// Based on operator<
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| 372 | template<typename _Tp, typename _Seq>
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| 373 | inline bool
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| 374 | operator>(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 375 | { return __y < __x; }
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| 376 |
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| 377 | /// Based on operator<
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| 378 | template<typename _Tp, typename _Seq>
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| 379 | inline bool
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| 380 | operator<=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 381 | { return !(__y < __x); }
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| 382 |
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| 383 | /// Based on operator<
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| 384 | template<typename _Tp, typename _Seq>
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| 385 | inline bool
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| 386 | operator>=(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 387 | { return !(__x < __y); }
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| 388 |
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| 389 | #if __cpp_lib_three_way_comparison
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| 390 | template<typename _Tp, three_way_comparable _Seq>
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| 391 | inline compare_three_way_result_t<_Seq>
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| 392 | operator<=>(const queue<_Tp, _Seq>& __x, const queue<_Tp, _Seq>& __y)
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| 393 | { return __x.c <=> __y.c; }
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| 394 | #endif
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| 395 |
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| 396 | #if __cplusplus >= 201103L
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| 397 | template<typename _Tp, typename _Seq>
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| 398 | inline
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| 399 | #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
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| 400 | // Constrained free swap overload, see p0185r1
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| 401 | typename enable_if<__is_swappable<_Seq>::value>::type
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| 402 | #else
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| 403 | void
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| 404 | #endif
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| 405 | swap(queue<_Tp, _Seq>& __x, queue<_Tp, _Seq>& __y)
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| 406 | noexcept(noexcept(__x.swap(__y)))
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| 407 | { __x.swap(__y); }
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| 408 |
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| 409 | template<typename _Tp, typename _Seq, typename _Alloc>
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| 410 | struct uses_allocator<queue<_Tp, _Seq>, _Alloc>
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| 411 | : public uses_allocator<_Seq, _Alloc>::type { };
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| 412 | #endif // __cplusplus >= 201103L
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| 413 |
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| 414 | /**
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| 415 | * @brief A standard container automatically sorting its contents.
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| 416 | *
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| 417 | * @ingroup sequences
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| 418 | *
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| 419 | * @tparam _Tp Type of element.
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| 420 | * @tparam _Sequence Type of underlying sequence, defaults to vector<_Tp>.
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| 421 | * @tparam _Compare Comparison function object type, defaults to
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| 422 | * less<_Sequence::value_type>.
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| 423 | *
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| 424 | * This is not a true container, but an @e adaptor. It holds
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| 425 | * another container, and provides a wrapper interface to that
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| 426 | * container. The wrapper is what enforces priority-based sorting
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| 427 | * and %queue behavior. Very few of the standard container/sequence
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| 428 | * interface requirements are met (e.g., iterators).
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| 429 | *
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| 430 | * The second template parameter defines the type of the underlying
|
---|
| 431 | * sequence/container. It defaults to std::vector, but it can be
|
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| 432 | * any type that supports @c front(), @c push_back, @c pop_back,
|
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| 433 | * and random-access iterators, such as std::deque or an
|
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| 434 | * appropriate user-defined type.
|
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| 435 | *
|
---|
| 436 | * The third template parameter supplies the means of making
|
---|
| 437 | * priority comparisons. It defaults to @c less<value_type> but
|
---|
| 438 | * can be anything defining a strict weak ordering.
|
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| 439 | *
|
---|
| 440 | * Members not found in @a normal containers are @c container_type,
|
---|
| 441 | * which is a typedef for the second Sequence parameter, and @c
|
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| 442 | * push, @c pop, and @c top, which are standard %queue operations.
|
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| 443 | *
|
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| 444 | * @note No equality/comparison operators are provided for
|
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| 445 | * %priority_queue.
|
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| 446 | *
|
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| 447 | * @note Sorting of the elements takes place as they are added to,
|
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| 448 | * and removed from, the %priority_queue using the
|
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| 449 | * %priority_queue's member functions. If you access the elements
|
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| 450 | * by other means, and change their data such that the sorting
|
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| 451 | * order would be different, the %priority_queue will not re-sort
|
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| 452 | * the elements for you. (How could it know to do so?)
|
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| 453 | */
|
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| 454 | template<typename _Tp, typename _Sequence = vector<_Tp>,
|
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| 455 | typename _Compare = less<typename _Sequence::value_type> >
|
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| 456 | class priority_queue
|
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| 457 | {
|
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| 458 | #ifdef _GLIBCXX_CONCEPT_CHECKS
|
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| 459 | // concept requirements
|
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| 460 | typedef typename _Sequence::value_type _Sequence_value_type;
|
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| 461 | # if __cplusplus < 201103L
|
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| 462 | __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
|
---|
| 463 | # endif
|
---|
| 464 | __glibcxx_class_requires(_Sequence, _SequenceConcept)
|
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| 465 | __glibcxx_class_requires(_Sequence, _RandomAccessContainerConcept)
|
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| 466 | __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
|
---|
| 467 | __glibcxx_class_requires4(_Compare, bool, _Tp, _Tp,
|
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| 468 | _BinaryFunctionConcept)
|
---|
| 469 | #endif
|
---|
| 470 |
|
---|
| 471 | #if __cplusplus >= 201103L
|
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| 472 | template<typename _Alloc>
|
---|
| 473 | using _Uses = typename
|
---|
| 474 | enable_if<uses_allocator<_Sequence, _Alloc>::value>::type;
|
---|
| 475 |
|
---|
| 476 | #if __cplusplus >= 201703L
|
---|
| 477 | // _GLIBCXX_RESOLVE_LIB_DEFECTS
|
---|
| 478 | // 2566. Requirements on the first template parameter of container
|
---|
| 479 | // adaptors
|
---|
| 480 | static_assert(is_same<_Tp, typename _Sequence::value_type>::value,
|
---|
| 481 | "value_type must be the same as the underlying container");
|
---|
| 482 | #endif // C++17
|
---|
| 483 | #endif // C++11
|
---|
| 484 |
|
---|
| 485 | public:
|
---|
| 486 | typedef typename _Sequence::value_type value_type;
|
---|
| 487 | typedef typename _Sequence::reference reference;
|
---|
| 488 | typedef typename _Sequence::const_reference const_reference;
|
---|
| 489 | typedef typename _Sequence::size_type size_type;
|
---|
| 490 | typedef _Sequence container_type;
|
---|
| 491 | // _GLIBCXX_RESOLVE_LIB_DEFECTS
|
---|
| 492 | // DR 2684. priority_queue lacking comparator typedef
|
---|
| 493 | typedef _Compare value_compare;
|
---|
| 494 |
|
---|
| 495 | protected:
|
---|
| 496 | // See queue::c for notes on these names.
|
---|
| 497 | _Sequence c;
|
---|
| 498 | _Compare comp;
|
---|
| 499 |
|
---|
| 500 | public:
|
---|
| 501 | /**
|
---|
| 502 | * @brief Default constructor creates no elements.
|
---|
| 503 | */
|
---|
| 504 | #if __cplusplus < 201103L
|
---|
| 505 | explicit
|
---|
| 506 | priority_queue(const _Compare& __x = _Compare(),
|
---|
| 507 | const _Sequence& __s = _Sequence())
|
---|
| 508 | : c(__s), comp(__x)
|
---|
| 509 | { std::make_heap(c.begin(), c.end(), comp); }
|
---|
| 510 | #else
|
---|
| 511 | template<typename _Seq = _Sequence, typename _Requires = typename
|
---|
| 512 | enable_if<__and_<is_default_constructible<_Compare>,
|
---|
| 513 | is_default_constructible<_Seq>>::value>::type>
|
---|
| 514 | priority_queue()
|
---|
| 515 | : c(), comp() { }
|
---|
| 516 |
|
---|
| 517 | explicit
|
---|
| 518 | priority_queue(const _Compare& __x, const _Sequence& __s)
|
---|
| 519 | : c(__s), comp(__x)
|
---|
| 520 | { std::make_heap(c.begin(), c.end(), comp); }
|
---|
| 521 |
|
---|
| 522 | explicit
|
---|
| 523 | priority_queue(const _Compare& __x, _Sequence&& __s = _Sequence())
|
---|
| 524 | : c(std::move(__s)), comp(__x)
|
---|
| 525 | { std::make_heap(c.begin(), c.end(), comp); }
|
---|
| 526 |
|
---|
| 527 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
---|
| 528 | explicit
|
---|
| 529 | priority_queue(const _Alloc& __a)
|
---|
| 530 | : c(__a), comp() { }
|
---|
| 531 |
|
---|
| 532 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
---|
| 533 | priority_queue(const _Compare& __x, const _Alloc& __a)
|
---|
| 534 | : c(__a), comp(__x) { }
|
---|
| 535 |
|
---|
| 536 | // _GLIBCXX_RESOLVE_LIB_DEFECTS
|
---|
| 537 | // 2537. Constructors [...] taking allocators should call make_heap
|
---|
| 538 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
---|
| 539 | priority_queue(const _Compare& __x, const _Sequence& __c,
|
---|
| 540 | const _Alloc& __a)
|
---|
| 541 | : c(__c, __a), comp(__x)
|
---|
| 542 | { std::make_heap(c.begin(), c.end(), comp); }
|
---|
| 543 |
|
---|
| 544 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
---|
| 545 | priority_queue(const _Compare& __x, _Sequence&& __c, const _Alloc& __a)
|
---|
| 546 | : c(std::move(__c), __a), comp(__x)
|
---|
| 547 | { std::make_heap(c.begin(), c.end(), comp); }
|
---|
| 548 |
|
---|
| 549 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
---|
| 550 | priority_queue(const priority_queue& __q, const _Alloc& __a)
|
---|
| 551 | : c(__q.c, __a), comp(__q.comp) { }
|
---|
| 552 |
|
---|
| 553 | template<typename _Alloc, typename _Requires = _Uses<_Alloc>>
|
---|
| 554 | priority_queue(priority_queue&& __q, const _Alloc& __a)
|
---|
| 555 | : c(std::move(__q.c), __a), comp(std::move(__q.comp)) { }
|
---|
| 556 | #endif
|
---|
| 557 |
|
---|
| 558 | /**
|
---|
| 559 | * @brief Builds a %queue from a range.
|
---|
| 560 | * @param __first An input iterator.
|
---|
| 561 | * @param __last An input iterator.
|
---|
| 562 | * @param __x A comparison functor describing a strict weak ordering.
|
---|
| 563 | * @param __s An initial sequence with which to start.
|
---|
| 564 | *
|
---|
| 565 | * Begins by copying @a __s, inserting a copy of the elements
|
---|
| 566 | * from @a [first,last) into the copy of @a __s, then ordering
|
---|
| 567 | * the copy according to @a __x.
|
---|
| 568 | *
|
---|
| 569 | * For more information on function objects, see the
|
---|
| 570 | * documentation on @link functors functor base
|
---|
| 571 | * classes@endlink.
|
---|
| 572 | */
|
---|
| 573 | #if __cplusplus < 201103L
|
---|
| 574 | template<typename _InputIterator>
|
---|
| 575 | priority_queue(_InputIterator __first, _InputIterator __last,
|
---|
| 576 | const _Compare& __x = _Compare(),
|
---|
| 577 | const _Sequence& __s = _Sequence())
|
---|
| 578 | : c(__s), comp(__x)
|
---|
| 579 | {
|
---|
| 580 | __glibcxx_requires_valid_range(__first, __last);
|
---|
| 581 | c.insert(c.end(), __first, __last);
|
---|
| 582 | std::make_heap(c.begin(), c.end(), comp);
|
---|
| 583 | }
|
---|
| 584 | #else
|
---|
| 585 | template<typename _InputIterator>
|
---|
| 586 | priority_queue(_InputIterator __first, _InputIterator __last,
|
---|
| 587 | const _Compare& __x,
|
---|
| 588 | const _Sequence& __s)
|
---|
| 589 | : c(__s), comp(__x)
|
---|
| 590 | {
|
---|
| 591 | __glibcxx_requires_valid_range(__first, __last);
|
---|
| 592 | c.insert(c.end(), __first, __last);
|
---|
| 593 | std::make_heap(c.begin(), c.end(), comp);
|
---|
| 594 | }
|
---|
| 595 |
|
---|
| 596 | template<typename _InputIterator>
|
---|
| 597 | priority_queue(_InputIterator __first, _InputIterator __last,
|
---|
| 598 | const _Compare& __x = _Compare(),
|
---|
| 599 | _Sequence&& __s = _Sequence())
|
---|
| 600 | : c(std::move(__s)), comp(__x)
|
---|
| 601 | {
|
---|
| 602 | __glibcxx_requires_valid_range(__first, __last);
|
---|
| 603 | c.insert(c.end(), __first, __last);
|
---|
| 604 | std::make_heap(c.begin(), c.end(), comp);
|
---|
| 605 | }
|
---|
| 606 | #endif
|
---|
| 607 |
|
---|
| 608 | /**
|
---|
| 609 | * Returns true if the %queue is empty.
|
---|
| 610 | */
|
---|
| 611 | _GLIBCXX_NODISCARD bool
|
---|
| 612 | empty() const
|
---|
| 613 | { return c.empty(); }
|
---|
| 614 |
|
---|
| 615 | /** Returns the number of elements in the %queue. */
|
---|
| 616 | size_type
|
---|
| 617 | size() const
|
---|
| 618 | { return c.size(); }
|
---|
| 619 |
|
---|
| 620 | /**
|
---|
| 621 | * Returns a read-only (constant) reference to the data at the first
|
---|
| 622 | * element of the %queue.
|
---|
| 623 | */
|
---|
| 624 | const_reference
|
---|
| 625 | top() const
|
---|
| 626 | {
|
---|
| 627 | __glibcxx_requires_nonempty();
|
---|
| 628 | return c.front();
|
---|
| 629 | }
|
---|
| 630 |
|
---|
| 631 | /**
|
---|
| 632 | * @brief Add data to the %queue.
|
---|
| 633 | * @param __x Data to be added.
|
---|
| 634 | *
|
---|
| 635 | * This is a typical %queue operation.
|
---|
| 636 | * The time complexity of the operation depends on the underlying
|
---|
| 637 | * sequence.
|
---|
| 638 | */
|
---|
| 639 | void
|
---|
| 640 | push(const value_type& __x)
|
---|
| 641 | {
|
---|
| 642 | c.push_back(__x);
|
---|
| 643 | std::push_heap(c.begin(), c.end(), comp);
|
---|
| 644 | }
|
---|
| 645 |
|
---|
| 646 | #if __cplusplus >= 201103L
|
---|
| 647 | void
|
---|
| 648 | push(value_type&& __x)
|
---|
| 649 | {
|
---|
| 650 | c.push_back(std::move(__x));
|
---|
| 651 | std::push_heap(c.begin(), c.end(), comp);
|
---|
| 652 | }
|
---|
| 653 |
|
---|
| 654 | template<typename... _Args>
|
---|
| 655 | void
|
---|
| 656 | emplace(_Args&&... __args)
|
---|
| 657 | {
|
---|
| 658 | c.emplace_back(std::forward<_Args>(__args)...);
|
---|
| 659 | std::push_heap(c.begin(), c.end(), comp);
|
---|
| 660 | }
|
---|
| 661 | #endif
|
---|
| 662 |
|
---|
| 663 | /**
|
---|
| 664 | * @brief Removes first element.
|
---|
| 665 | *
|
---|
| 666 | * This is a typical %queue operation. It shrinks the %queue
|
---|
| 667 | * by one. The time complexity of the operation depends on the
|
---|
| 668 | * underlying sequence.
|
---|
| 669 | *
|
---|
| 670 | * Note that no data is returned, and if the first element's
|
---|
| 671 | * data is needed, it should be retrieved before pop() is
|
---|
| 672 | * called.
|
---|
| 673 | */
|
---|
| 674 | void
|
---|
| 675 | pop()
|
---|
| 676 | {
|
---|
| 677 | __glibcxx_requires_nonempty();
|
---|
| 678 | std::pop_heap(c.begin(), c.end(), comp);
|
---|
| 679 | c.pop_back();
|
---|
| 680 | }
|
---|
| 681 |
|
---|
| 682 | #if __cplusplus >= 201103L
|
---|
| 683 | void
|
---|
| 684 | swap(priority_queue& __pq)
|
---|
| 685 | noexcept(__and_<
|
---|
| 686 | #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
---|
| 687 | __is_nothrow_swappable<_Sequence>,
|
---|
| 688 | #else
|
---|
| 689 | __is_nothrow_swappable<_Tp>,
|
---|
| 690 | #endif
|
---|
| 691 | __is_nothrow_swappable<_Compare>
|
---|
| 692 | >::value)
|
---|
| 693 | {
|
---|
| 694 | using std::swap;
|
---|
| 695 | swap(c, __pq.c);
|
---|
| 696 | swap(comp, __pq.comp);
|
---|
| 697 | }
|
---|
| 698 | #endif // __cplusplus >= 201103L
|
---|
| 699 | };
|
---|
| 700 |
|
---|
| 701 | #if __cpp_deduction_guides >= 201606
|
---|
| 702 | template<typename _Compare, typename _Container,
|
---|
| 703 | typename = _RequireNotAllocator<_Compare>,
|
---|
| 704 | typename = _RequireNotAllocator<_Container>>
|
---|
| 705 | priority_queue(_Compare, _Container)
|
---|
| 706 | -> priority_queue<typename _Container::value_type, _Container, _Compare>;
|
---|
| 707 |
|
---|
| 708 | template<typename _InputIterator, typename _ValT
|
---|
| 709 | = typename iterator_traits<_InputIterator>::value_type,
|
---|
| 710 | typename _Compare = less<_ValT>,
|
---|
| 711 | typename _Container = vector<_ValT>,
|
---|
| 712 | typename = _RequireInputIter<_InputIterator>,
|
---|
| 713 | typename = _RequireNotAllocator<_Compare>,
|
---|
| 714 | typename = _RequireNotAllocator<_Container>>
|
---|
| 715 | priority_queue(_InputIterator, _InputIterator, _Compare = _Compare(),
|
---|
| 716 | _Container = _Container())
|
---|
| 717 | -> priority_queue<_ValT, _Container, _Compare>;
|
---|
| 718 |
|
---|
| 719 | template<typename _Compare, typename _Container, typename _Allocator,
|
---|
| 720 | typename = _RequireNotAllocator<_Compare>,
|
---|
| 721 | typename = _RequireNotAllocator<_Container>,
|
---|
| 722 | typename = _RequireAllocator<_Allocator>>
|
---|
| 723 | priority_queue(_Compare, _Container, _Allocator)
|
---|
| 724 | -> priority_queue<typename _Container::value_type, _Container, _Compare>;
|
---|
| 725 | #endif
|
---|
| 726 |
|
---|
| 727 | // No equality/comparison operators are provided for priority_queue.
|
---|
| 728 |
|
---|
| 729 | #if __cplusplus >= 201103L
|
---|
| 730 | template<typename _Tp, typename _Sequence, typename _Compare>
|
---|
| 731 | inline
|
---|
| 732 | #if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or gnu++11
|
---|
| 733 | // Constrained free swap overload, see p0185r1
|
---|
| 734 | typename enable_if<__and_<__is_swappable<_Sequence>,
|
---|
| 735 | __is_swappable<_Compare>>::value>::type
|
---|
| 736 | #else
|
---|
| 737 | void
|
---|
| 738 | #endif
|
---|
| 739 | swap(priority_queue<_Tp, _Sequence, _Compare>& __x,
|
---|
| 740 | priority_queue<_Tp, _Sequence, _Compare>& __y)
|
---|
| 741 | noexcept(noexcept(__x.swap(__y)))
|
---|
| 742 | { __x.swap(__y); }
|
---|
| 743 |
|
---|
| 744 | template<typename _Tp, typename _Sequence, typename _Compare,
|
---|
| 745 | typename _Alloc>
|
---|
| 746 | struct uses_allocator<priority_queue<_Tp, _Sequence, _Compare>, _Alloc>
|
---|
| 747 | : public uses_allocator<_Sequence, _Alloc>::type { };
|
---|
| 748 | #endif // __cplusplus >= 201103L
|
---|
| 749 |
|
---|
| 750 | _GLIBCXX_END_NAMESPACE_VERSION
|
---|
| 751 | } // namespace
|
---|
| 752 |
|
---|
| 753 | #endif /* _STL_QUEUE_H */
|
---|