1// -*- C++ -*-
2
3// Copyright (C) 2005-2013 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
33// purpose. It is provided "as is" without express or implied
34// warranty.
35
36/**
37 * @file pairing_heap_/pairing_heap_.hpp
38 * Contains an implementation class for a pairing heap.
39 */
40
41/*
42 * Pairing heap:
43 * Michael L. Fredman, Robert Sedgewick, Daniel Dominic Sleator,
44 *    and Robert Endre Tarjan, The Pairing Heap:
45 *    A New Form of Self-Adjusting Heap, Algorithmica, 1(1):111-129, 1986.
46 */
47
48#include <ext/pb_ds/detail/cond_dealtor.hpp>
49#include <ext/pb_ds/detail/type_utils.hpp>
50#include <ext/pb_ds/detail/left_child_next_sibling_heap_/left_child_next_sibling_heap_.hpp>
51#include <debug/debug.h>
52
53namespace __gnu_pbds
54{
55  namespace detail
56  {
57#define PB_DS_CLASS_T_DEC \
58  template<typename Value_Type, typename Cmp_Fn, typename _Alloc>
59
60#define PB_DS_CLASS_C_DEC \
61  pairing_heap<Value_Type, Cmp_Fn, _Alloc>
62
63#ifdef _GLIBCXX_DEBUG
64#define PB_DS_P_HEAP_BASE \
65  left_child_next_sibling_heap<Value_Type, Cmp_Fn, null_type, _Alloc, false>
66#else
67#define PB_DS_P_HEAP_BASE \
68  left_child_next_sibling_heap<Value_Type, Cmp_Fn, null_type, _Alloc>
69#endif
70
71    /**
72     *  Pairing heap.
73     *
74     *  @ingroup heap-detail
75     */
76    template<typename Value_Type, typename Cmp_Fn, typename _Alloc>
77    class pairing_heap : public PB_DS_P_HEAP_BASE
78    {
79    private:
80      typedef PB_DS_P_HEAP_BASE				base_type;
81      typedef typename base_type::node_pointer 		node_pointer;
82
83      typedef typename _Alloc::template rebind<Value_Type>::other __rebind_a;
84
85    public:
86      typedef Value_Type 				value_type;
87      typedef Cmp_Fn 					cmp_fn;
88      typedef _Alloc 					allocator_type;
89      typedef typename _Alloc::size_type 		size_type;
90      typedef typename _Alloc::difference_type 		difference_type;
91
92      typedef typename __rebind_a::pointer 		pointer;
93      typedef typename __rebind_a::const_pointer 	const_pointer;
94      typedef typename __rebind_a::reference		reference;
95      typedef typename __rebind_a::const_reference 	const_reference;
96
97      typedef typename base_type::point_const_iterator	point_const_iterator;
98      typedef typename base_type::point_iterator 	point_iterator;
99      typedef typename base_type::const_iterator 	const_iterator;
100      typedef typename base_type::iterator 		iterator;
101
102      pairing_heap();
103
104      pairing_heap(const Cmp_Fn&);
105
106      pairing_heap(const pairing_heap&);
107
108      void
109      swap(pairing_heap&);
110
111      ~pairing_heap();
112
113      inline point_iterator
114      push(const_reference);
115
116      void
117      modify(point_iterator, const_reference);
118
119      inline const_reference
120      top() const;
121
122      void
123      pop();
124
125      void
126      erase(point_iterator);
127
128      template<typename Pred>
129      size_type
130      erase_if(Pred);
131
132      template<typename Pred>
133      void
134      split(Pred, pairing_heap&);
135
136      void
137      join(pairing_heap&);
138
139    protected:
140
141      template<typename It>
142      void
143      copy_from_range(It, It);
144
145#ifdef _GLIBCXX_DEBUG
146      void
147      assert_valid(const char*, int) const;
148#endif
149
150    private:
151
152      inline void
153      push_imp(node_pointer);
154
155      node_pointer
156      join_node_children(node_pointer);
157
158      node_pointer
159      forward_join(node_pointer, node_pointer);
160
161      node_pointer
162      back_join(node_pointer, node_pointer);
163
164      void
165      remove_node(node_pointer);
166    };
167
168#define PB_DS_ASSERT_NODE_CONSISTENT(_Node, _Bool) \
169 _GLIBCXX_DEBUG_ONLY(base_type::assert_node_consistent(_Node, _Bool,	\
170						       __FILE__, __LINE__);)
171
172#include <ext/pb_ds/detail/pairing_heap_/constructors_destructor_fn_imps.hpp>
173#include <ext/pb_ds/detail/pairing_heap_/debug_fn_imps.hpp>
174#include <ext/pb_ds/detail/pairing_heap_/find_fn_imps.hpp>
175#include <ext/pb_ds/detail/pairing_heap_/insert_fn_imps.hpp>
176#include <ext/pb_ds/detail/pairing_heap_/erase_fn_imps.hpp>
177#include <ext/pb_ds/detail/pairing_heap_/split_join_fn_imps.hpp>
178
179#undef PB_DS_ASSERT_NODE_CONSISTENT
180#undef PB_DS_CLASS_C_DEC
181#undef PB_DS_CLASS_T_DEC
182#undef PB_DS_P_HEAP_BASE
183
184  } // namespace detail
185} // namespace __gnu_pbds
186