contrib/gcc-8.0/libstdc++-v3/include/ext/pb_ds/detail/binomial_heap_base_/erase_fn_imps.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2018 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_/erase_fn_imps.hpp
  38  * Contains an implementation class for a base of binomial heaps.
  39  */
  40
  41 PB_DS_CLASS_T_DEC
  42 void
  43 PB_DS_CLASS_C_DEC::
  44 pop()
  45 {
  46   PB_DS_ASSERT_VALID_COND((*this),true)
  47   _GLIBCXX_DEBUG_ASSERT(!base_type::empty());
  48
  49   if (m_p_max == 0)
  50     find_max();
  51
  52   _GLIBCXX_DEBUG_ASSERT(m_p_max != 0);
  53   node_pointer p_nd = m_p_max;
  54   remove_parentless_node(m_p_max);
  55   base_type::actual_erase_node(p_nd);
  56   m_p_max = 0;
  57   PB_DS_ASSERT_VALID_COND((*this),true)
  58 }
  59
  60 PB_DS_CLASS_T_DEC
  61 void
  62 PB_DS_CLASS_C_DEC::
  63 remove_parentless_node(node_pointer p_nd)
  64 {
  65   _GLIBCXX_DEBUG_ASSERT(p_nd != 0);
  66   _GLIBCXX_DEBUG_ASSERT(base_type::parent(p_nd) == 0);
  67
  68   node_pointer p_cur_root = p_nd == base_type::m_p_root?
  69     p_nd->m_p_next_sibling : base_type::m_p_root;
  70
  71   if (p_cur_root != 0)
  72     p_cur_root->m_p_prev_or_parent = 0;
  73
  74   if (p_nd->m_p_prev_or_parent != 0)
  75     p_nd->m_p_prev_or_parent->m_p_next_sibling = p_nd->m_p_next_sibling;
  76
  77   if (p_nd->m_p_next_sibling != 0)
  78     p_nd->m_p_next_sibling->m_p_prev_or_parent = p_nd->m_p_prev_or_parent;
  79
  80   node_pointer p_child = p_nd->m_p_l_child;
  81   if (p_child != 0)
  82     {
  83       p_child->m_p_prev_or_parent = 0;
  84       while (p_child->m_p_next_sibling != 0)
  85         p_child = p_child->m_p_next_sibling;
  86     }
  87
  88   m_p_max = 0;
  89   base_type::m_p_root = join(p_cur_root, p_child);
  90 }
  91
  92 PB_DS_CLASS_T_DEC
  93 inline void
  94 PB_DS_CLASS_C_DEC::
  95 clear()
  96 {
  97   base_type::clear();
  98   m_p_max = 0;
  99 }
 100
 101 PB_DS_CLASS_T_DEC
 102 void
 103 PB_DS_CLASS_C_DEC::
 104 erase(point_iterator it)
 105 {
 106   PB_DS_ASSERT_VALID_COND((*this),true)
 107   _GLIBCXX_DEBUG_ASSERT(!base_type::empty());
 108
 109   base_type::bubble_to_top(it.m_p_nd);
 110   remove_parentless_node(it.m_p_nd);
 111   base_type::actual_erase_node(it.m_p_nd);
 112   m_p_max = 0;
 113   PB_DS_ASSERT_VALID_COND((*this),true)
 114 }
 115
 116 PB_DS_CLASS_T_DEC
 117 template<typename Pred>
 118 typename PB_DS_CLASS_C_DEC::size_type
 119 PB_DS_CLASS_C_DEC::
 120 erase_if(Pred pred)
 121 {
 122   PB_DS_ASSERT_VALID_COND((*this),true)
 123
 124   if (base_type::empty())
 125     {
 126       PB_DS_ASSERT_VALID_COND((*this),true)
 127       return 0;
 128     }
 129
 130   base_type::to_linked_list();
 131   node_pointer p_out = base_type::prune(pred);
 132   size_type ersd = 0;
 133   while (p_out != 0)
 134     {
 135       ++ersd;
 136       node_pointer p_next = p_out->m_p_next_sibling;
 137       base_type::actual_erase_node(p_out);
 138       p_out = p_next;
 139     }
 140
 141   node_pointer p_cur = base_type::m_p_root;
 142   base_type::m_p_root = 0;
 143   while (p_cur != 0)
 144     {
 145       node_pointer p_next = p_cur->m_p_next_sibling;
 146       p_cur->m_p_l_child = p_cur->m_p_prev_or_parent = 0;
 147       p_cur->m_metadata = 0;
 148       p_cur->m_p_next_sibling = base_type::m_p_root;
 149
 150       if (base_type::m_p_root != 0)
 151         base_type::m_p_root->m_p_prev_or_parent = p_cur;
 152
 153       base_type::m_p_root = p_cur;
 154       base_type::m_p_root = fix(base_type::m_p_root);
 155       p_cur = p_next;
 156     }
 157
 158   m_p_max = 0;
 159   PB_DS_ASSERT_VALID_COND((*this),true)
 160   return ersd;
 161 }