libstdc++
binomial_heap_base_/split_join_fn_imps.hpp
Go to the documentation of this file.
1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2017 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 PB_DS_CLASS_T_DEC
42 template<typename Pred>
43 void
44 PB_DS_CLASS_C_DEC::
45 split(Pred pred, PB_DS_CLASS_C_DEC& other)
46 {
47  PB_DS_ASSERT_VALID_COND((*this),true)
48  PB_DS_ASSERT_VALID_COND(other,true)
49 
50  other.clear();
51  if (base_type::empty())
52  {
53  PB_DS_ASSERT_VALID_COND((*this),true)
54  PB_DS_ASSERT_VALID_COND(other,true)
55  return;
56  }
57 
58  base_type::to_linked_list();
59  node_pointer p_out = base_type::prune(pred);
60  while (p_out != 0)
61  {
62  _GLIBCXX_DEBUG_ASSERT(base_type::m_size > 0);
63  --base_type::m_size;
64  ++other.m_size;
65 
66  node_pointer p_next = p_out->m_p_next_sibling;
67  p_out->m_p_l_child = p_out->m_p_prev_or_parent = 0;
68  p_out->m_metadata = 0;
69 
70  p_out->m_p_next_sibling = other.m_p_root;
71  if (other.m_p_root != 0)
72  other.m_p_root->m_p_prev_or_parent = p_out;
73 
74  other.m_p_root = p_out;
75  other.m_p_root = other.fix(other.m_p_root);
76  p_out = p_next;
77  }
78 
79  PB_DS_ASSERT_VALID_COND(other,true)
80  node_pointer p_cur = base_type::m_p_root;
81  base_type::m_p_root = 0;
82 
83  while (p_cur != 0)
84  {
85  node_pointer p_next = p_cur->m_p_next_sibling;
86  p_cur->m_p_l_child = p_cur->m_p_prev_or_parent = 0;
87  p_cur->m_metadata = 0;
88  p_cur->m_p_next_sibling = base_type::m_p_root;
89 
90  if (base_type::m_p_root != 0)
91  base_type::m_p_root->m_p_prev_or_parent = p_cur;
92 
93  base_type::m_p_root = p_cur;
94  base_type::m_p_root = fix(base_type::m_p_root);
95  p_cur = p_next;
96  }
97 
98  m_p_max = 0;
99  PB_DS_ASSERT_VALID_COND((*this),true)
100  PB_DS_ASSERT_VALID_COND(other,true)
101 }
102 
103 PB_DS_CLASS_T_DEC
104 inline void
105 PB_DS_CLASS_C_DEC::
106 join(PB_DS_CLASS_C_DEC& other)
107 {
108  PB_DS_ASSERT_VALID_COND((*this),true)
109  PB_DS_ASSERT_VALID_COND(other,true)
110 
111  node_pointer p_other = other.m_p_root;
112  if (p_other != 0)
113  do
114  {
115  node_pointer p_next = p_other->m_p_next_sibling;
116  std::swap(p_other->m_p_next_sibling, p_other->m_p_prev_or_parent);
117  p_other = p_next;
118  }
119  while (p_other != 0);
120 
121  base_type::m_p_root = join(base_type::m_p_root, other.m_p_root);
122  base_type::m_size += other.m_size;
123  m_p_max = 0;
124 
125  other.m_p_root = 0;
126  other.m_size = 0;
127  other.m_p_max = 0;
128 
129  PB_DS_ASSERT_VALID_COND((*this),true)
130  PB_DS_ASSERT_VALID_COND(other,true)
131 }
132 
133 PB_DS_CLASS_T_DEC
134 inline typename PB_DS_CLASS_C_DEC::node_pointer
135 PB_DS_CLASS_C_DEC::
136 join(node_pointer p_lhs, node_pointer p_rhs) const
137 {
138  node_pointer p_ret = 0;
139  node_pointer p_cur = 0;
140 
141  while (p_lhs != 0 || p_rhs != 0)
142  {
143  if (p_rhs == 0)
144  {
145  if (p_cur == 0)
146  p_ret = p_cur = p_lhs;
147  else
148  {
149  p_cur->m_p_next_sibling = p_lhs;
150  p_lhs->m_p_prev_or_parent = p_cur;
151  }
152  p_cur = p_lhs = 0;
153  }
154  else if (p_lhs == 0 || p_rhs->m_metadata < p_lhs->m_metadata)
155  {
156  if (p_cur == 0)
157  {
158  p_ret = p_cur = p_rhs;
159  p_rhs = p_rhs->m_p_prev_or_parent;
160  }
161  else
162  {
163  p_cur->m_p_next_sibling = p_rhs;
164  p_rhs = p_rhs->m_p_prev_or_parent;
165  p_cur->m_p_next_sibling->m_p_prev_or_parent = p_cur;
166  p_cur = p_cur->m_p_next_sibling;
167  }
168  }
169  else if (p_lhs->m_metadata < p_rhs->m_metadata)
170  {
171  if (p_cur == 0)
172  p_ret = p_cur = p_lhs;
173  else
174  {
175  p_cur->m_p_next_sibling = p_lhs;
176  p_lhs->m_p_prev_or_parent = p_cur;
177  p_cur = p_cur->m_p_next_sibling;
178  }
179  p_lhs = p_cur->m_p_next_sibling;
180  }
181  else
182  {
183  node_pointer p_next_rhs = p_rhs->m_p_prev_or_parent;
184  p_rhs->m_p_next_sibling = p_lhs;
185  p_lhs = fix(p_rhs);
186  p_rhs = p_next_rhs;
187  }
188  }
189 
190  if (p_cur != 0)
191  p_cur->m_p_next_sibling = 0;
192 
193  if (p_ret != 0)
194  p_ret->m_p_prev_or_parent = 0;
195 
196  return p_ret;
197 }