libstdc++: rc.hpp Source File

libstdc++

rc.hpp
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1// -*- C++ -*-
2
3// Copyright (C) 2005-2026 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the terms
7// of the GNU General Public License as published by the Free Software
8// Foundation; either version 3, or (at your option) any later
9// version.
10
11// This library is distributed in the hope that it will be useful, but
12// WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14// General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
26
27// Permission to use, copy, modify, sell, and distribute this software
28// is hereby granted without fee, provided that the above copyright
29// notice appears in all copies, and that both that copyright notice
30// and this permission notice appear in supporting documentation. None
31// of the above authors, nor IBM Haifa Research Laboratories, make any
32// representation about the suitability of this software for any
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34// warranty.
35
36/**
37 * @file rc_binomial_heap_/rc.hpp
38 * Contains a redundant (binary counter).
39 */
40
41#ifndef PB_DS_RC_HPP
42#define PB_DS_RC_HPP
43
44namespace __gnu_pbds
45{
46 namespace detail
47 {
48 /// Redundant binary counter.
49 template<typename _Node, typename _Alloc>
50 class rc
51 {
52 private:
53 typedef _Alloc allocator_type;
54 typedef typename allocator_type::size_type size_type;
55 typedef _Node node;
56
57 typedef typename rebind_traits<_Alloc, node>::pointer node_pointer;
58
59
60 typedef typename rebind_traits<_Alloc, node_pointer>::pointer
61 entry_pointer;
62 typedef typename rebind_traits<_Alloc, node_pointer>::const_pointer
63 entry_const_pointer;
64
65 enum
66 {
67 max_entries = sizeof(size_type) << 3
68 };
69
70 public:
71 typedef node_pointer entry;
72 typedef entry_const_pointer const_iterator;
73
74 rc();
75
76 rc(const rc&);
77
78 inline void
79 swap(rc&);
80
81 inline void
82 push(entry);
83
84 inline node_pointer
85 top() const;
86
87 inline void
88 pop();
89
90 _GLIBCXX_NODISCARD inline bool
91 empty() const;
92
93 inline size_type
94 size() const;
95
96 void
97 clear();
98
99 const const_iterator
100 begin() const;
101
102 const const_iterator
103 end() const;
104
105#ifdef _GLIBCXX_DEBUG
106 void
107 assert_valid(const char*, int) const;
108#endif
109
110#ifdef PB_DS_RC_BINOMIAL_HEAP_TRACE_
111 void
112 trace() const;
113#endif
114
115 private:
116 node_pointer m_a_entries[max_entries];
117 size_type m_over_top;
118 };
119
120 template<typename _Node, typename _Alloc>
121 rc<_Node, _Alloc>::
122 rc() : m_over_top(0)
123 { PB_DS_ASSERT_VALID((*this)) }
124
125 template<typename _Node, typename _Alloc>
126 rc<_Node, _Alloc>::
127 rc(const rc<_Node, _Alloc>& other) : m_over_top(0)
128 { PB_DS_ASSERT_VALID((*this)) }
129
130 template<typename _Node, typename _Alloc>
131 inline void
132 rc<_Node, _Alloc>::
133 swap(rc<_Node, _Alloc>& other)
134 {
135 PB_DS_ASSERT_VALID((*this))
136 PB_DS_ASSERT_VALID(other)
137
138 const size_type over_top = std::max(m_over_top, other.m_over_top);
139
140 for (size_type i = 0; i < over_top; ++i)
141 std::swap(m_a_entries[i], other.m_a_entries[i]);
142
143 std::swap(m_over_top, other.m_over_top);
144 PB_DS_ASSERT_VALID((*this))
145 PB_DS_ASSERT_VALID(other)
146 }
147
148 template<typename _Node, typename _Alloc>
149 inline void
150 rc<_Node, _Alloc>::
151 push(entry p_nd)
152 {
153 PB_DS_ASSERT_VALID((*this))
154 _GLIBCXX_DEBUG_ASSERT(m_over_top < max_entries);
155 m_a_entries[m_over_top++] = p_nd;
156 PB_DS_ASSERT_VALID((*this))
157 }
158
159 template<typename _Node, typename _Alloc>
160 inline void
161 rc<_Node, _Alloc>::
162 pop()
163 {
164 PB_DS_ASSERT_VALID((*this))
165 _GLIBCXX_DEBUG_ASSERT(!empty());
166 --m_over_top;
167 PB_DS_ASSERT_VALID((*this))
168 }
169
170 template<typename _Node, typename _Alloc>
171 inline typename rc<_Node, _Alloc>::node_pointer
172 rc<_Node, _Alloc>::
173 top() const
174 {
175 PB_DS_ASSERT_VALID((*this))
176 _GLIBCXX_DEBUG_ASSERT(!empty());
177 return *(m_a_entries + m_over_top - 1);
178 }
179
180 template<typename _Node, typename _Alloc>
181 _GLIBCXX_NODISCARD inline bool
182 rc<_Node, _Alloc>::
183 empty() const
184 {
185 PB_DS_ASSERT_VALID((*this))
186 return m_over_top == 0;
187 }
188
189 template<typename _Node, typename _Alloc>
190 inline typename rc<_Node, _Alloc>::size_type
191 rc<_Node, _Alloc>::
192 size() const
193 { return m_over_top; }
194
195 template<typename _Node, typename _Alloc>
196 void
197 rc<_Node, _Alloc>::
198 clear()
199 {
200 PB_DS_ASSERT_VALID((*this))
201 m_over_top = 0;
202 PB_DS_ASSERT_VALID((*this))
203 }
204
205 template<typename _Node, typename _Alloc>
206 const typename rc<_Node, _Alloc>::const_iterator
207 rc<_Node, _Alloc>::
208 begin() const
209 { return& m_a_entries[0]; }
210
211 template<typename _Node, typename _Alloc>
212 const typename rc<_Node, _Alloc>::const_iterator
213 rc<_Node, _Alloc>::
214 end() const
215 { return& m_a_entries[m_over_top]; }
216
217#ifdef _GLIBCXX_DEBUG
218 template<typename _Node, typename _Alloc>
219 void
220 rc<_Node, _Alloc>::
221 assert_valid(const char* __file, int __line) const
222 { PB_DS_DEBUG_VERIFY(m_over_top < max_entries); }
223#endif
224
225#ifdef PB_DS_RC_BINOMIAL_HEAP_TRACE_
226 template<typename _Node, typename _Alloc>
227 void
228 rc<_Node, _Alloc>::
229 trace() const
230 {
231 std::cout << "rc" << std::endl;
232 for (size_type i = 0; i < m_over_top; ++i)
233 std::cerr << m_a_entries[i] << std::endl;
234 std::cout << std::endl;
235 }
236#endif
237} // namespace detail
238} // namespace __gnu_pbds
239
240#endif
std
ISO C++ entities toplevel namespace is std.
std::endl
basic_ostream< _CharT, _Traits > & endl(basic_ostream< _CharT, _Traits > &__os)
Write a newline and flush the stream.
Definition ostream:71
std::cerr
ostream cerr
Linked to standard error (unbuffered)
std::cout
ostream cout
Linked to standard output.
__gnu_pbds
GNU extensions for policy-based data structures for public use.
Definition assoc_container.hpp:52
__gnu_pbds::detail::rebind_traits
Consistent API for accessing allocator-related types.
Definition types_traits.hpp:140
__gnu_pbds::detail::rc
Redundant binary counter.
Definition rc.hpp:51