libstdc++-v3/include/ext/pb_ds/detail/binomial_heap_base_/split_join_fn_imps.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2023 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_/split_join_fn_imps.hpp
  38  * Contains an implementation class for a base of binomial heaps.
  39  */
  40
  41 #ifdef PB_DS_CLASS_C_DEC
  42
  43 PB_DS_CLASS_T_DEC
  44 template<typename Pred>
  45 void
  46 PB_DS_CLASS_C_DEC::
  47 split(Pred pred, PB_DS_CLASS_C_DEC& other)
  48 {
  49   PB_DS_ASSERT_VALID_COND((*this),true)
  50   PB_DS_ASSERT_VALID_COND(other,true)
  51
  52   other.clear();
  53   if (base_type::empty())
  54     {
  55       PB_DS_ASSERT_VALID_COND((*this),true)
  56       PB_DS_ASSERT_VALID_COND(other,true)
  57       return;
  58     }
  59
  60   base_type::to_linked_list();
  61   node_pointer p_out = base_type::prune(pred);
  62   while (p_out != 0)
  63     {
  64       _GLIBCXX_DEBUG_ASSERT(base_type::m_size > 0);
  65       --base_type::m_size;
  66       ++other.m_size;
  67
  68       node_pointer p_next = p_out->m_p_next_sibling;
  69       p_out->m_p_l_child = p_out->m_p_prev_or_parent = 0;
  70       p_out->m_metadata = 0;
  71
  72       p_out->m_p_next_sibling = other.m_p_root;
  73       if (other.m_p_root != 0)
  74         other.m_p_root->m_p_prev_or_parent = p_out;
  75
  76       other.m_p_root = p_out;
  77       other.m_p_root = other.fix(other.m_p_root);
  78       p_out = p_next;
  79     }
  80
  81   PB_DS_ASSERT_VALID_COND(other,true)
  82   node_pointer p_cur = base_type::m_p_root;
  83   base_type::m_p_root = 0;
  84
  85   while (p_cur != 0)
  86     {
  87       node_pointer p_next = p_cur->m_p_next_sibling;
  88       p_cur->m_p_l_child = p_cur->m_p_prev_or_parent = 0;
  89       p_cur->m_metadata = 0;
  90       p_cur->m_p_next_sibling = base_type::m_p_root;
  91
  92       if (base_type::m_p_root != 0)
  93         base_type::m_p_root->m_p_prev_or_parent = p_cur;
  94
  95       base_type::m_p_root = p_cur;
  96       base_type::m_p_root = fix(base_type::m_p_root);
  97       p_cur = p_next;
  98     }
  99
 100   m_p_max = 0;
 101   PB_DS_ASSERT_VALID_COND((*this),true)
 102   PB_DS_ASSERT_VALID_COND(other,true)
 103 }
 104
 105 PB_DS_CLASS_T_DEC
 106 inline void
 107 PB_DS_CLASS_C_DEC::
 108 join(PB_DS_CLASS_C_DEC& other)
 109 {
 110   PB_DS_ASSERT_VALID_COND((*this),true)
 111   PB_DS_ASSERT_VALID_COND(other,true)
 112
 113   node_pointer p_other = other.m_p_root;
 114   if (p_other != 0)
 115     do
 116       {
 117         node_pointer p_next = p_other->m_p_next_sibling;
 118         std::swap(p_other->m_p_next_sibling, p_other->m_p_prev_or_parent);
 119         p_other = p_next;
 120       }
 121     while (p_other != 0);
 122
 123   base_type::m_p_root = join(base_type::m_p_root, other.m_p_root);
 124   base_type::m_size += other.m_size;
 125   m_p_max = 0;
 126
 127   other.m_p_root = 0;
 128   other.m_size = 0;
 129   other.m_p_max = 0;
 130
 131   PB_DS_ASSERT_VALID_COND((*this),true)
 132   PB_DS_ASSERT_VALID_COND(other,true)
 133 }
 134
 135 PB_DS_CLASS_T_DEC
 136 inline typename PB_DS_CLASS_C_DEC::node_pointer
 137 PB_DS_CLASS_C_DEC::
 138 join(node_pointer p_lhs, node_pointer p_rhs) const
 139 {
 140   node_pointer p_ret = 0;
 141   node_pointer p_cur = 0;
 142
 143   while (p_lhs != 0 || p_rhs != 0)
 144     {
 145       if (p_rhs == 0)
 146         {
 147           if (p_cur == 0)
 148             p_ret = p_cur = p_lhs;
 149           else
 150             {
 151               p_cur->m_p_next_sibling = p_lhs;
 152               p_lhs->m_p_prev_or_parent = p_cur;
 153             }
 154           p_cur = p_lhs = 0;
 155         }
 156       else if (p_lhs == 0 || p_rhs->m_metadata < p_lhs->m_metadata)
 157         {
 158           if (p_cur == 0)
 159             {
 160               p_ret = p_cur = p_rhs;
 161               p_rhs = p_rhs->m_p_prev_or_parent;
 162             }
 163           else
 164             {
 165               p_cur->m_p_next_sibling = p_rhs;
 166               p_rhs = p_rhs->m_p_prev_or_parent;
 167               p_cur->m_p_next_sibling->m_p_prev_or_parent = p_cur;
 168               p_cur = p_cur->m_p_next_sibling;
 169             }
 170         }
 171       else if (p_lhs->m_metadata < p_rhs->m_metadata)
 172         {
 173           if (p_cur == 0)
 174             p_ret = p_cur = p_lhs;
 175           else
 176             {
 177               p_cur->m_p_next_sibling = p_lhs;
 178               p_lhs->m_p_prev_or_parent = p_cur;
 179               p_cur = p_cur->m_p_next_sibling;
 180             }
 181           p_lhs = p_cur->m_p_next_sibling;
 182         }
 183       else
 184         {
 185           node_pointer p_next_rhs = p_rhs->m_p_prev_or_parent;
 186           p_rhs->m_p_next_sibling = p_lhs;
 187           p_lhs = fix(p_rhs);
 188           p_rhs = p_next_rhs;
 189         }
 190     }
 191
 192   if (p_cur != 0)
 193     p_cur->m_p_next_sibling = 0;
 194
 195   if (p_ret != 0)
 196     p_ret->m_p_prev_or_parent = 0;
 197
 198   return p_ret;
 199 }
 200 #endif