1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2022 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 #ifdef PB_DS_CLASS_C_DEC
42 
43 PB_DS_CLASS_T_DEC
44 void
45 PB_DS_CLASS_C_DEC::
pop()46 pop()
47 {
48   PB_DS_ASSERT_VALID_COND((*this),true)
49   _GLIBCXX_DEBUG_ASSERT(!base_type::empty());
50 
51   if (m_p_max == 0)
52     find_max();
53 
54   _GLIBCXX_DEBUG_ASSERT(m_p_max != 0);
55   node_pointer p_nd = m_p_max;
56   remove_parentless_node(m_p_max);
57   base_type::actual_erase_node(p_nd);
58   m_p_max = 0;
59   PB_DS_ASSERT_VALID_COND((*this),true)
60 }
61 
62 PB_DS_CLASS_T_DEC
63 void
64 PB_DS_CLASS_C_DEC::
remove_parentless_node(node_pointer p_nd)65 remove_parentless_node(node_pointer p_nd)
66 {
67   _GLIBCXX_DEBUG_ASSERT(p_nd != 0);
68   _GLIBCXX_DEBUG_ASSERT(base_type::parent(p_nd) == 0);
69 
70   node_pointer p_cur_root = p_nd == base_type::m_p_root?
71     p_nd->m_p_next_sibling : base_type::m_p_root;
72 
73   if (p_cur_root != 0)
74     p_cur_root->m_p_prev_or_parent = 0;
75 
76   if (p_nd->m_p_prev_or_parent != 0)
77     p_nd->m_p_prev_or_parent->m_p_next_sibling = p_nd->m_p_next_sibling;
78 
79   if (p_nd->m_p_next_sibling != 0)
80     p_nd->m_p_next_sibling->m_p_prev_or_parent = p_nd->m_p_prev_or_parent;
81 
82   node_pointer p_child = p_nd->m_p_l_child;
83   if (p_child != 0)
84     {
85       p_child->m_p_prev_or_parent = 0;
86       while (p_child->m_p_next_sibling != 0)
87           p_child = p_child->m_p_next_sibling;
88     }
89 
90   m_p_max = 0;
91   base_type::m_p_root = join(p_cur_root, p_child);
92 }
93 
94 PB_DS_CLASS_T_DEC
95 inline void
96 PB_DS_CLASS_C_DEC::
clear()97 clear()
98 {
99   base_type::clear();
100   m_p_max = 0;
101 }
102 
103 PB_DS_CLASS_T_DEC
104 void
105 PB_DS_CLASS_C_DEC::
erase(point_iterator it)106 erase(point_iterator it)
107 {
108   PB_DS_ASSERT_VALID_COND((*this),true)
109   _GLIBCXX_DEBUG_ASSERT(!base_type::empty());
110 
111   base_type::bubble_to_top(it.m_p_nd);
112   remove_parentless_node(it.m_p_nd);
113   base_type::actual_erase_node(it.m_p_nd);
114   m_p_max = 0;
115   PB_DS_ASSERT_VALID_COND((*this),true)
116 }
117 
118 PB_DS_CLASS_T_DEC
119 template<typename Pred>
120 typename PB_DS_CLASS_C_DEC::size_type
121 PB_DS_CLASS_C_DEC::
erase_if(Pred pred)122 erase_if(Pred pred)
123 {
124   PB_DS_ASSERT_VALID_COND((*this),true)
125 
126   if (base_type::empty())
127     {
128       PB_DS_ASSERT_VALID_COND((*this),true)
129       return 0;
130     }
131 
132   base_type::to_linked_list();
133   node_pointer p_out = base_type::prune(pred);
134   size_type ersd = 0;
135   while (p_out != 0)
136     {
137       ++ersd;
138       node_pointer p_next = p_out->m_p_next_sibling;
139       base_type::actual_erase_node(p_out);
140       p_out = p_next;
141     }
142 
143   node_pointer p_cur = base_type::m_p_root;
144   base_type::m_p_root = 0;
145   while (p_cur != 0)
146     {
147       node_pointer p_next = p_cur->m_p_next_sibling;
148       p_cur->m_p_l_child = p_cur->m_p_prev_or_parent = 0;
149       p_cur->m_metadata = 0;
150       p_cur->m_p_next_sibling = base_type::m_p_root;
151 
152       if (base_type::m_p_root != 0)
153           base_type::m_p_root->m_p_prev_or_parent = p_cur;
154 
155       base_type::m_p_root = p_cur;
156       base_type::m_p_root = fix(base_type::m_p_root);
157       p_cur = p_next;
158     }
159 
160   m_p_max = 0;
161   PB_DS_ASSERT_VALID_COND((*this),true)
162   return ersd;
163 }
164 #endif
165