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

   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