libstdc++-v3/include/ext/pb_ds/detail/bin_search_tree_/rotate_fn_imps.hpp

   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 bin_search_tree_/rotate_fn_imps.hpp
  38  * Contains imps for rotating nodes.
  39  */
  40
  41 PB_DS_CLASS_T_DEC
  42 inline void
  43 PB_DS_CLASS_C_DEC::
  44 rotate_left(node_pointer p_x)
  45 {
  46   node_pointer p_y = p_x->m_p_right;
  47
  48   p_x->m_p_right = p_y->m_p_left;
  49
  50   if (p_y->m_p_left != 0)
  51     p_y->m_p_left->m_p_parent = p_x;
  52
  53   p_y->m_p_parent = p_x->m_p_parent;
  54
  55   if (p_x == m_p_head->m_p_parent)
  56     m_p_head->m_p_parent = p_y;
  57   else if (p_x == p_x->m_p_parent->m_p_left)
  58     p_x->m_p_parent->m_p_left = p_y;
  59   else
  60     p_x->m_p_parent->m_p_right = p_y;
  61
  62   p_y->m_p_left = p_x;
  63   p_x->m_p_parent = p_y;
  64
  65   PB_DS_ASSERT_NODE_CONSISTENT(p_x)
  66   PB_DS_ASSERT_NODE_CONSISTENT(p_y)
  67
  68   apply_update(p_x, (node_update* )this);
  69   apply_update(p_x->m_p_parent, (node_update* )this);
  70 }
  71
  72 PB_DS_CLASS_T_DEC
  73 inline void
  74 PB_DS_CLASS_C_DEC::
  75 rotate_right(node_pointer p_x)
  76 {
  77   node_pointer p_y = p_x->m_p_left;
  78
  79   p_x->m_p_left = p_y->m_p_right;
  80
  81   if (p_y->m_p_right != 0)
  82     p_y->m_p_right->m_p_parent = p_x;
  83
  84   p_y->m_p_parent = p_x->m_p_parent;
  85
  86   if (p_x == m_p_head->m_p_parent)
  87     m_p_head->m_p_parent = p_y;
  88   else if (p_x == p_x->m_p_parent->m_p_right)
  89     p_x->m_p_parent->m_p_right = p_y;
  90   else
  91     p_x->m_p_parent->m_p_left = p_y;
  92
  93   p_y->m_p_right = p_x;
  94   p_x->m_p_parent = p_y;
  95
  96   PB_DS_ASSERT_NODE_CONSISTENT(p_x)
  97   PB_DS_ASSERT_NODE_CONSISTENT(p_y)
  98
  99   apply_update(p_x, (node_update* )this);
 100   apply_update(p_x->m_p_parent, (node_update* )this);
 101 }
 102
 103 PB_DS_CLASS_T_DEC
 104 inline void
 105 PB_DS_CLASS_C_DEC::
 106 rotate_parent(node_pointer p_nd)
 107 {
 108   node_pointer p_parent = p_nd->m_p_parent;
 109
 110   if (p_nd == p_parent->m_p_left)
 111     rotate_right(p_parent);
 112   else
 113     rotate_left(p_parent);
 114
 115   _GLIBCXX_DEBUG_ASSERT(p_parent->m_p_parent = p_nd);
 116   _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_left == p_parent ||
 117                    p_nd->m_p_right == p_parent);
 118 }
 119
 120 PB_DS_CLASS_T_DEC
 121 inline void
 122 PB_DS_CLASS_C_DEC::
 123 apply_update(node_pointer /*p_nd*/, null_node_update_pointer /*p_update*/)
 124 { }
 125
 126 PB_DS_CLASS_T_DEC
 127 template<typename Node_Update_>
 128 inline void
 129 PB_DS_CLASS_C_DEC::
 130 apply_update(node_pointer p_nd, Node_Update_*  /*p_update*/)
 131 {
 132   node_update::operator()(node_iterator(p_nd),
 133                           node_const_iterator(static_cast<node_pointer>(0)));
 134 }
 135
 136 PB_DS_CLASS_T_DEC
 137 template<typename Node_Update_>
 138 inline void
 139 PB_DS_CLASS_C_DEC::
 140 update_to_top(node_pointer p_nd, Node_Update_* p_update)
 141 {
 142   while (p_nd != m_p_head)
 143     {
 144       apply_update(p_nd, p_update);
 145
 146       p_nd = p_nd->m_p_parent;
 147     }
 148 }
 149
 150 PB_DS_CLASS_T_DEC
 151 inline void
 152 PB_DS_CLASS_C_DEC::
 153 update_to_top(node_pointer /*p_nd*/, null_node_update_pointer /*p_update*/)
 154 { }
 155