xref: /openbsd-src/gnu/gcc/libstdc++-v3/include/ext/pb_ds/detail/binomial_heap_base_/split_join_fn_imps.hpp (revision 404b540a9034ac75a6199ad1a32d1bbc7a0d4210)
1 // -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006 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 2, 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 // You should have received a copy of the GNU General Public License
17 // along with this library; see the file COPYING.  If not, write to
18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
19 // MA 02111-1307, USA.
20 
21 // As a special exception, you may use this file as part of a free
22 // software library without restriction.  Specifically, if other files
23 // instantiate templates or use macros or inline functions from this
24 // file, or you compile this file and link it with other files to
25 // produce an executable, this file does not by itself cause the
26 // resulting executable to be covered by the GNU General Public
27 // License.  This exception does not however invalidate any other
28 // reasons why the executable file might be covered by the GNU General
29 // Public License.
30 
31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
32 
33 // Permission to use, copy, modify, sell, and distribute this software
34 // is hereby granted without fee, provided that the above copyright
35 // notice appears in all copies, and that both that copyright notice
36 // and this permission notice appear in supporting documentation. None
37 // of the above authors, nor IBM Haifa Research Laboratories, make any
38 // representation about the suitability of this software for any
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40 // warranty.
41 
42 /**
43  * @file split_join_fn_imps.hpp
44  * Contains an implementation class for a base of binomial heaps.
45  */
46 
47 PB_DS_CLASS_T_DEC
48 template<typename Pred>
49 void
50 PB_DS_CLASS_C_DEC::
split(Pred pred,PB_DS_CLASS_C_DEC & other)51 split(Pred pred, PB_DS_CLASS_C_DEC& other)
52 {
53   _GLIBCXX_DEBUG_ONLY(assert_valid(true);)
54     _GLIBCXX_DEBUG_ONLY(other.assert_valid(true);)
55 
56     other.clear();
57 
58   if (base_type::empty())
59     {
60       _GLIBCXX_DEBUG_ONLY(assert_valid(true);)
61         _GLIBCXX_DEBUG_ONLY(other.assert_valid(true);)
62 
63         return;
64     }
65 
66   base_type::to_linked_list();
67 
68   node_pointer p_out = base_type::prune(pred);
69 
70   while (p_out != NULL)
71     {
72       _GLIBCXX_DEBUG_ASSERT(base_type::m_size > 0);
73       --base_type::m_size;
74 
75       ++other.m_size;
76 
77       node_pointer p_next = p_out->m_p_next_sibling;
78 
79       p_out->m_p_l_child = p_out->m_p_prev_or_parent = NULL;
80 
81       p_out->m_metadata = 0;
82 
83       p_out->m_p_next_sibling = other.m_p_root;
84 
85       if (other.m_p_root != NULL)
86 	other.m_p_root->m_p_prev_or_parent = p_out;
87 
88       other.m_p_root = p_out;
89 
90       other.m_p_root = other.fix(other.m_p_root);
91 
92       p_out = p_next;
93     }
94 
95   _GLIBCXX_DEBUG_ONLY(other.assert_valid(true);)
96 
97     node_pointer p_cur = base_type::m_p_root;
98 
99   base_type::m_p_root = NULL;
100 
101   while (p_cur != NULL)
102     {
103       node_pointer p_next = p_cur->m_p_next_sibling;
104 
105       p_cur->m_p_l_child = p_cur->m_p_prev_or_parent = NULL;
106 
107       p_cur->m_metadata = 0;
108 
109       p_cur->m_p_next_sibling = base_type::m_p_root;
110 
111       if (base_type::m_p_root != NULL)
112 	base_type::m_p_root->m_p_prev_or_parent = p_cur;
113 
114       base_type::m_p_root = p_cur;
115 
116       base_type::m_p_root = fix(base_type::m_p_root);
117 
118       p_cur = p_next;
119     }
120 
121   m_p_max = NULL;
122 
123   _GLIBCXX_DEBUG_ONLY(assert_valid(true);)
124     _GLIBCXX_DEBUG_ONLY(other.assert_valid(true);)
125     }
126 
127 PB_DS_CLASS_T_DEC
128 inline void
129 PB_DS_CLASS_C_DEC::
join(PB_DS_CLASS_C_DEC & other)130 join(PB_DS_CLASS_C_DEC& other)
131 {
132   _GLIBCXX_DEBUG_ONLY(assert_valid(true);)
133     _GLIBCXX_DEBUG_ONLY(other.assert_valid(true);)
134 
135     node_pointer p_other = other.m_p_root;
136 
137   if (p_other != NULL)
138     do
139       {
140 	node_pointer p_next = p_other->m_p_next_sibling;
141 
142 	std::swap(p_other->m_p_next_sibling, p_other->m_p_prev_or_parent);
143 
144 	p_other = p_next;
145       }
146     while (p_other != NULL);
147 
148   base_type::m_p_root = join(base_type::m_p_root, other.m_p_root);
149   base_type::m_size += other.m_size;
150   m_p_max = NULL;
151 
152   other.m_p_root = NULL;
153   other.m_size = 0;
154   other.m_p_max = NULL;
155 
156   _GLIBCXX_DEBUG_ONLY(assert_valid(true);)
157     _GLIBCXX_DEBUG_ONLY(other.assert_valid(true);)
158     }
159 
160 PB_DS_CLASS_T_DEC
161 inline typename PB_DS_CLASS_C_DEC::node_pointer
162 PB_DS_CLASS_C_DEC::
join(node_pointer p_lhs,node_pointer p_rhs) const163 join(node_pointer p_lhs, node_pointer p_rhs) const
164 {
165   node_pointer p_ret = NULL;
166 
167   node_pointer p_cur = NULL;
168 
169   while (p_lhs != NULL || p_rhs != NULL)
170     {
171       if (p_rhs == NULL)
172         {
173 	  if (p_cur == NULL)
174 	    p_ret = p_cur = p_lhs;
175 	  else
176             {
177 	      p_cur->m_p_next_sibling = p_lhs;
178 
179 	      p_lhs->m_p_prev_or_parent = p_cur;
180             }
181 
182 	  p_cur = p_lhs = NULL;
183         }
184       else if (p_lhs == NULL || p_rhs->m_metadata < p_lhs->m_metadata)
185         {
186 	  if (p_cur == NULL)
187             {
188 	      p_ret = p_cur = p_rhs;
189 
190 	      p_rhs = p_rhs->m_p_prev_or_parent;
191             }
192 	  else
193             {
194 	      p_cur->m_p_next_sibling = p_rhs;
195 
196 	      p_rhs = p_rhs->m_p_prev_or_parent;
197 
198 	      p_cur->m_p_next_sibling->m_p_prev_or_parent = p_cur;
199 
200 	      p_cur = p_cur->m_p_next_sibling;
201             }
202         }
203       else if (p_lhs->m_metadata < p_rhs->m_metadata)
204         {
205 	  if (p_cur == NULL)
206 	    p_ret = p_cur = p_lhs;
207 	  else
208             {
209 	      p_cur->m_p_next_sibling = p_lhs;
210 
211 	      p_lhs->m_p_prev_or_parent = p_cur;
212 
213 	      p_cur = p_cur->m_p_next_sibling;
214             }
215 
216 	  p_lhs = p_cur->m_p_next_sibling;
217         }
218       else
219         {
220 	  node_pointer p_next_rhs = p_rhs->m_p_prev_or_parent;
221 
222 	  p_rhs->m_p_next_sibling = p_lhs;
223 
224 	  p_lhs = fix(p_rhs);
225 
226 	  p_rhs = p_next_rhs;
227         }
228     }
229 
230   if (p_cur != NULL)
231     p_cur->m_p_next_sibling = NULL;
232 
233   if (p_ret != NULL)
234     p_ret->m_p_prev_or_parent = NULL;
235 
236   return p_ret;
237 }
238 
239