libstdc++
bin_search_tree_/rotate_fn_imps.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2020 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 
43 PB_DS_CLASS_T_DEC
44 inline void
45 PB_DS_CLASS_C_DEC::
46 rotate_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 
74 PB_DS_CLASS_T_DEC
75 inline void
76 PB_DS_CLASS_C_DEC::
77 rotate_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 
105 PB_DS_CLASS_T_DEC
106 inline void
107 PB_DS_CLASS_C_DEC::
108 rotate_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 
122 PB_DS_CLASS_T_DEC
123 inline void
124 PB_DS_CLASS_C_DEC::
125 apply_update(node_pointer /*p_nd*/, null_node_update_pointer /*p_update*/)
126 { }
127 
128 PB_DS_CLASS_T_DEC
129 template<typename Node_Update_>
130 inline void
131 PB_DS_CLASS_C_DEC::
132 apply_update(node_pointer p_nd, Node_Update_* /*p_update*/)
133 {
134  node_update::operator()(node_iterator(p_nd),
135  node_const_iterator(static_cast<node_pointer>(0)));
136 }
137 
138 PB_DS_CLASS_T_DEC
139 template<typename Node_Update_>
140 inline void
141 PB_DS_CLASS_C_DEC::
142 update_to_top(node_pointer p_nd, Node_Update_* p_update)
143 {
144  while (p_nd != m_p_head)
145  {
146  apply_update(p_nd, p_update);
147 
148  p_nd = p_nd->m_p_parent;
149  }
150 }
151 
152 PB_DS_CLASS_T_DEC
153 inline void
154 PB_DS_CLASS_C_DEC::
155 update_to_top(node_pointer /*p_nd*/, null_node_update_pointer /*p_update*/)
156 { }
157 
158 #endif