libstdc++
splay_tree_/erase_fn_imps.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006, 2009, 2010, 2011 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
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8 // Foundation; either version 3, or (at your option) any later
9 // version.
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11 // This library is distributed in the hope that it will be useful, but
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14 // General Public License for more details.
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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.
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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
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24 
25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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27 // Permission to use, copy, modify, sell, and distribute this software
28 // is hereby granted without fee, provided that the above copyright
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35 
36 /**
37  * @file splay_tree_/erase_fn_imps.hpp
38  * Contains an implementation class for splay_tree_.
39  */
40 
41 PB_DS_CLASS_T_DEC
42 inline bool
43 PB_DS_CLASS_C_DEC::
44 erase(key_const_reference r_key)
45 {
46  point_iterator it = find(r_key);
47  if (it == base_type::end())
48  return false;
49  erase(it);
50  return true;
51 }
52 
53 PB_DS_CLASS_T_DEC
54 inline typename PB_DS_CLASS_C_DEC::iterator
55 PB_DS_CLASS_C_DEC::
56 erase(iterator it)
57 {
58  PB_DS_ASSERT_VALID((*this))
59  if (it == base_type::end())
60  return it;
61  iterator ret_it = it;
62  ++ret_it;
63  erase_node(it.m_p_nd);
64  PB_DS_ASSERT_VALID((*this))
65  return ret_it;
66 }
67 
68 PB_DS_CLASS_T_DEC
69 inline typename PB_DS_CLASS_C_DEC::reverse_iterator
70 PB_DS_CLASS_C_DEC::
71 erase(reverse_iterator it)
72 {
73  PB_DS_ASSERT_VALID((*this))
74  if (it.m_p_nd == base_type::m_p_head)
75  return (it);
76  reverse_iterator ret_it = it;
77  ++ret_it;
78  erase_node(it.m_p_nd);
79  PB_DS_ASSERT_VALID((*this))
80  return ret_it;
81 }
82 
83 PB_DS_CLASS_T_DEC
84 template<typename Pred>
85 inline typename PB_DS_CLASS_C_DEC::size_type
86 PB_DS_CLASS_C_DEC::
87 erase_if(Pred pred)
88 {
89  PB_DS_ASSERT_VALID((*this))
90  size_type num_ersd = 0;
91  iterator it = base_type::begin();
92  while (it != base_type::end())
93  {
94  if (pred(*it))
95  {
96  ++num_ersd;
97  it = erase(it);
98  }
99  else
100  ++it;
101  }
102  PB_DS_ASSERT_VALID((*this))
103  return num_ersd;
104 }
105 
106 PB_DS_CLASS_T_DEC
107 void
108 PB_DS_CLASS_C_DEC::
109 erase_node(node_pointer p_nd)
110 {
111  _GLIBCXX_DEBUG_ASSERT(p_nd != 0);
112  splay(p_nd);
113 
114  PB_DS_ASSERT_VALID((*this))
115  _GLIBCXX_DEBUG_ASSERT(p_nd == this->m_p_head->m_p_parent);
116 
117  node_pointer p_l = p_nd->m_p_left;
118  node_pointer p_r = p_nd->m_p_right;
119 
120  base_type::update_min_max_for_erased_node(p_nd);
121  base_type::actual_erase_node(p_nd);
122  if (p_r == 0)
123  {
124  base_type::m_p_head->m_p_parent = p_l;
125  if (p_l != 0)
126  p_l->m_p_parent = base_type::m_p_head;
127  PB_DS_ASSERT_VALID((*this))
128  return;
129  }
130 
131  node_pointer p_target_r = leftmost(p_r);
132  _GLIBCXX_DEBUG_ASSERT(p_target_r != 0);
133  p_r->m_p_parent = base_type::m_p_head;
134  base_type::m_p_head->m_p_parent = p_r;
135  splay(p_target_r);
136 
137  _GLIBCXX_DEBUG_ONLY(p_target_r->m_p_left = 0);
138  _GLIBCXX_DEBUG_ASSERT(p_target_r->m_p_parent == this->m_p_head);
139  _GLIBCXX_DEBUG_ASSERT(this->m_p_head->m_p_parent == p_target_r);
140 
141  p_target_r->m_p_left = p_l;
142  if (p_l != 0)
143  p_l->m_p_parent = p_target_r;
144  PB_DS_ASSERT_VALID((*this))
145  this->apply_update(p_target_r, (node_update*)this);
146 }
147 
148 PB_DS_CLASS_T_DEC
149 inline typename PB_DS_CLASS_C_DEC::node_pointer
150 PB_DS_CLASS_C_DEC::
151 leftmost(node_pointer p_nd)
152 {
153  _GLIBCXX_DEBUG_ASSERT(p_nd != 0);
154  while (p_nd->m_p_left != 0)
155  p_nd = p_nd->m_p_left;
156  return p_nd;
157 }