libstdc++
binomial_heap_base_/erase_fn_imps.hpp
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1// -*- C++ -*-
2
3// Copyright (C) 2005-2019 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 binomial_heap_base_/erase_fn_imps.hpp
38 * Contains an implementation class for a base of binomial heaps.
39 */
40
41PB_DS_CLASS_T_DEC
42void
43PB_DS_CLASS_C_DEC::
44pop()
45{
46 PB_DS_ASSERT_VALID_COND((*this),true)
47 _GLIBCXX_DEBUG_ASSERT(!base_type::empty());
48
49 if (m_p_max == 0)
50 find_max();
51
52 _GLIBCXX_DEBUG_ASSERT(m_p_max != 0);
53 node_pointer p_nd = m_p_max;
54 remove_parentless_node(m_p_max);
55 base_type::actual_erase_node(p_nd);
56 m_p_max = 0;
57 PB_DS_ASSERT_VALID_COND((*this),true)
58}
59
60PB_DS_CLASS_T_DEC
61void
62PB_DS_CLASS_C_DEC::
63remove_parentless_node(node_pointer p_nd)
64{
65 _GLIBCXX_DEBUG_ASSERT(p_nd != 0);
66 _GLIBCXX_DEBUG_ASSERT(base_type::parent(p_nd) == 0);
67
68 node_pointer p_cur_root = p_nd == base_type::m_p_root?
69 p_nd->m_p_next_sibling : base_type::m_p_root;
70
71 if (p_cur_root != 0)
72 p_cur_root->m_p_prev_or_parent = 0;
73
74 if (p_nd->m_p_prev_or_parent != 0)
75 p_nd->m_p_prev_or_parent->m_p_next_sibling = p_nd->m_p_next_sibling;
76
77 if (p_nd->m_p_next_sibling != 0)
78 p_nd->m_p_next_sibling->m_p_prev_or_parent = p_nd->m_p_prev_or_parent;
79
80 node_pointer p_child = p_nd->m_p_l_child;
81 if (p_child != 0)
82 {
83 p_child->m_p_prev_or_parent = 0;
84 while (p_child->m_p_next_sibling != 0)
85 p_child = p_child->m_p_next_sibling;
86 }
87
88 m_p_max = 0;
89 base_type::m_p_root = join(p_cur_root, p_child);
90}
91
92PB_DS_CLASS_T_DEC
93inline void
94PB_DS_CLASS_C_DEC::
95clear()
96{
97 base_type::clear();
98 m_p_max = 0;
99}
100
101PB_DS_CLASS_T_DEC
102void
103PB_DS_CLASS_C_DEC::
104erase(point_iterator it)
105{
106 PB_DS_ASSERT_VALID_COND((*this),true)
107 _GLIBCXX_DEBUG_ASSERT(!base_type::empty());
108
109 base_type::bubble_to_top(it.m_p_nd);
110 remove_parentless_node(it.m_p_nd);
111 base_type::actual_erase_node(it.m_p_nd);
112 m_p_max = 0;
113 PB_DS_ASSERT_VALID_COND((*this),true)
114}
115
116PB_DS_CLASS_T_DEC
117template<typename Pred>
118typename PB_DS_CLASS_C_DEC::size_type
119PB_DS_CLASS_C_DEC::
120erase_if(Pred pred)
121{
122 PB_DS_ASSERT_VALID_COND((*this),true)
123
124 if (base_type::empty())
125 {
126 PB_DS_ASSERT_VALID_COND((*this),true)
127 return 0;
128 }
129
130 base_type::to_linked_list();
131 node_pointer p_out = base_type::prune(pred);
132 size_type ersd = 0;
133 while (p_out != 0)
134 {
135 ++ersd;
136 node_pointer p_next = p_out->m_p_next_sibling;
137 base_type::actual_erase_node(p_out);
138 p_out = p_next;
139 }
140
141 node_pointer p_cur = base_type::m_p_root;
142 base_type::m_p_root = 0;
143 while (p_cur != 0)
144 {
145 node_pointer p_next = p_cur->m_p_next_sibling;
146 p_cur->m_p_l_child = p_cur->m_p_prev_or_parent = 0;
147 p_cur->m_metadata = 0;
148 p_cur->m_p_next_sibling = base_type::m_p_root;
149
150 if (base_type::m_p_root != 0)
151 base_type::m_p_root->m_p_prev_or_parent = p_cur;
152
153 base_type::m_p_root = p_cur;
154 base_type::m_p_root = fix(base_type::m_p_root);
155 p_cur = p_next;
156 }
157
158 m_p_max = 0;
159 PB_DS_ASSERT_VALID_COND((*this),true)
160 return ersd;
161}