libstdc++: rotate_fn_imps.hpp Source File

libstdc++

bin_search_tree_/rotate_fn_imps.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
33// purpose. It is provided "as is" without express or implied
34// warranty.
35
36/**
37 * @file bin_search_tree_/rotate_fn_imps.hpp
38 * Contains imps for rotating nodes.
39 */
40
41#ifdef PB_DS_CLASS_C_DEC
42
43PB_DS_CLASS_T_DEC
44inline void
45PB_DS_CLASS_C_DEC::
46rotate_left(node_pointer p_x)
47{
48 node_pointer p_y = p_x->m_p_right;
49
50 p_x->m_p_right = p_y->m_p_left;
51
52 if (p_y->m_p_left != 0)
53 p_y->m_p_left->m_p_parent = p_x;
54
55 p_y->m_p_parent = p_x->m_p_parent;
56
57 if (p_x == m_p_head->m_p_parent)
58 m_p_head->m_p_parent = p_y;
59 else if (p_x == p_x->m_p_parent->m_p_left)
60 p_x->m_p_parent->m_p_left = p_y;
61 else
62 p_x->m_p_parent->m_p_right = p_y;
63
64 p_y->m_p_left = p_x;
65 p_x->m_p_parent = p_y;
66
67 PB_DS_ASSERT_NODE_CONSISTENT(p_x)
68 PB_DS_ASSERT_NODE_CONSISTENT(p_y)
69
70 apply_update(p_x, (node_update* )this);
71 apply_update(p_x->m_p_parent, (node_update* )this);
72}
73
74PB_DS_CLASS_T_DEC
75inline void
76PB_DS_CLASS_C_DEC::
77rotate_right(node_pointer p_x)
78{
79 node_pointer p_y = p_x->m_p_left;
80
81 p_x->m_p_left = p_y->m_p_right;
82
83 if (p_y->m_p_right != 0)
84 p_y->m_p_right->m_p_parent = p_x;
85
86 p_y->m_p_parent = p_x->m_p_parent;
87
88 if (p_x == m_p_head->m_p_parent)
89 m_p_head->m_p_parent = p_y;
90 else if (p_x == p_x->m_p_parent->m_p_right)
91 p_x->m_p_parent->m_p_right = p_y;
92 else
93 p_x->m_p_parent->m_p_left = p_y;
94
95 p_y->m_p_right = p_x;
96 p_x->m_p_parent = p_y;
97
98 PB_DS_ASSERT_NODE_CONSISTENT(p_x)
99 PB_DS_ASSERT_NODE_CONSISTENT(p_y)
100
101 apply_update(p_x, (node_update* )this);
102 apply_update(p_x->m_p_parent, (node_update* )this);
103}
104
105PB_DS_CLASS_T_DEC
106inline void
107PB_DS_CLASS_C_DEC::
108rotate_parent(node_pointer p_nd)
109{
110 node_pointer p_parent = p_nd->m_p_parent;
111
112 if (p_nd == p_parent->m_p_left)
113 rotate_right(p_parent);
114 else
115 rotate_left(p_parent);
116
117 _GLIBCXX_DEBUG_ASSERT(p_parent->m_p_parent = p_nd);
118 _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_left == p_parent ||
119 p_nd->m_p_right == p_parent);
120}
121
122PB_DS_CLASS_T_DEC
123inline void
124PB_DS_CLASS_C_DEC::
125update_subtree_size(node_pointer p_nd)
126{
127 size_type size = 1;
128 if (p_nd->m_p_left)
129 size += p_nd->m_p_left->m_subtree_size;
130 if (p_nd->m_p_right)
131 size += p_nd->m_p_right->m_subtree_size;
132 p_nd->m_subtree_size = size;
133}
134
135PB_DS_CLASS_T_DEC
136inline void
137PB_DS_CLASS_C_DEC::
138apply_update(node_pointer p_nd, null_node_update_pointer /*p_update*/)
139{
140 update_subtree_size(p_nd);
141}
142
143PB_DS_CLASS_T_DEC
144template<typename Node_Update_>
145inline void
146PB_DS_CLASS_C_DEC::
147apply_update(node_pointer p_nd, Node_Update_* /*p_update*/)
148{
149 update_subtree_size(p_nd);
150 node_update::operator()(node_iterator(p_nd),
151 node_const_iterator(static_cast<node_pointer>(0)));
152}
153
154PB_DS_CLASS_T_DEC
155template<typename Node_Update_>
156inline void
157PB_DS_CLASS_C_DEC::
158update_to_top(node_pointer p_nd, Node_Update_* p_update)
159{
160 while (p_nd != m_p_head)
161 {
162 apply_update(p_nd, p_update);
163
164 p_nd = p_nd->m_p_parent;
165 }
166}
167
168PB_DS_CLASS_T_DEC
169inline void
170PB_DS_CLASS_C_DEC::
171update_to_top(node_pointer p_nd, null_node_update_pointer /*p_update */)
172{
173 while (p_nd != m_p_head)
174 {
175 update_subtree_size(p_nd);
176
177 p_nd = p_nd->m_p_parent;
178 }
179}
180
181#endif