libstdc++

binary_heap_/insert_fn_imps.hpp
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1 // -*- C++ -*-
2
3 // Copyright (C) 2005-2013 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 binary_heap_/insert_fn_imps.hpp
38 * Contains an implementation class for a binary_heap.
39 */
40
41 PB_DS_CLASS_T_DEC
42 inline typename PB_DS_CLASS_C_DEC::point_iterator
43 PB_DS_CLASS_C_DEC::
44 push(const_reference r_val)
45 {
46 PB_DS_ASSERT_VALID((*this))
47 insert_value(r_val, s_no_throw_copies_ind);
48 push_heap();
49 PB_DS_ASSERT_VALID((*this))
50 return point_iterator(m_a_entries);
51 }
52
53 PB_DS_CLASS_T_DEC
54 inline void
55 PB_DS_CLASS_C_DEC::
56 insert_value(value_type val, true_type)
57 {
58 resize_for_insert_if_needed();
59 m_a_entries[m_size++] = val;
60 }
61
62 PB_DS_CLASS_T_DEC
63 inline void
64 PB_DS_CLASS_C_DEC::
65 insert_value(const_reference r_val, false_type)
66 {
67 resize_for_insert_if_needed();
68 pointer p_new = s_value_allocator.allocate(1);
69 cond_dealtor_t cond(p_new);
70 new (p_new) value_type(r_val);
71 cond.set_no_action();
72 m_a_entries[m_size++] = p_new;
73 }
74
75 PB_DS_CLASS_T_DEC
76 inline void
77 PB_DS_CLASS_C_DEC::
78 resize_for_insert_if_needed()
79 {
80 if (!resize_policy::resize_needed_for_grow(m_size))
81 {
82 _GLIBCXX_DEBUG_ASSERT(m_size < m_actual_size);
83 return;
84 }
85
86 const size_type new_size = resize_policy::get_new_size_for_grow();
87 entry_pointer new_entries = s_entry_allocator.allocate(new_size);
88 resize_policy::notify_grow_resize();
89
90 std::copy(m_a_entries, m_a_entries + m_size, new_entries);
91 s_entry_allocator.deallocate(m_a_entries, m_actual_size);
92 m_actual_size = new_size;
93 m_a_entries = new_entries;
94 make_heap();
95 }
96
97 PB_DS_CLASS_T_DEC
98 void
99 PB_DS_CLASS_C_DEC::
100 modify(point_iterator it, const_reference r_new_val)
101 {
102 PB_DS_ASSERT_VALID((*this))
103 swap_value_imp(it.m_p_e, r_new_val, s_no_throw_copies_ind);
104 fix(it.m_p_e);
105 PB_DS_ASSERT_VALID((*this))
106 _GLIBCXX_DEBUG_ASSERT(is_heap());
107 }
108
109 PB_DS_CLASS_T_DEC
110 void
111 PB_DS_CLASS_C_DEC::
112 fix(entry_pointer p_e)
113 {
114 size_type i = p_e - m_a_entries;
115 if (i > 0 && entry_cmp::operator()(m_a_entries[parent(i)], m_a_entries[i]))
116 {
117 size_type parent_i = parent(i);
118 while (i > 0
119 && entry_cmp::operator()(m_a_entries[parent_i], m_a_entries[i]))
120 {
121 std::swap(m_a_entries[i], m_a_entries[parent_i]);
122 i = parent_i;
123 parent_i = parent(i);
124 }
125
126 PB_DS_ASSERT_VALID((*this))
127 return;
128 }
129
130 while (i < m_size)
131 {
132 const size_type lchild_i = left_child(i);
133 const size_type rchild_i = right_child(i);
134 _GLIBCXX_DEBUG_ASSERT(rchild_i > lchild_i);
135
136 const bool smaller_than_lchild = lchild_i < m_size &&
137 entry_cmp::operator()(m_a_entries[i], m_a_entries[lchild_i]);
138
139 const bool smaller_than_rchild = rchild_i < m_size &&
140 entry_cmp::operator()(m_a_entries[i], m_a_entries[rchild_i]);
141
142 const bool swap_with_rchild = smaller_than_rchild && (!smaller_than_lchild || entry_cmp::operator()(m_a_entries[lchild_i], m_a_entries[rchild_i]));
143
144 const bool swap_with_lchild = !swap_with_rchild && smaller_than_lchild;
145
146 if (swap_with_lchild)
147 {
148 std::swap(m_a_entries[i], m_a_entries[lchild_i]);
149 i = lchild_i;
150 }
151 else if (swap_with_rchild)
152 {
153 std::swap(m_a_entries[i], m_a_entries[rchild_i]);
154 i = rchild_i;
155 }
156 else
157 i = m_size;
158 }
159 }
160
161 PB_DS_CLASS_T_DEC
162 inline void
163 PB_DS_CLASS_C_DEC::
164 swap_value_imp(entry_pointer p_e, value_type new_val, true_type)
165 { *p_e = new_val; }
166
167 PB_DS_CLASS_T_DEC
168 inline void
169 PB_DS_CLASS_C_DEC::
170 swap_value_imp(entry_pointer p_e, const_reference r_new_val, false_type)
171 {
172 value_type tmp(r_new_val);
173 (*p_e)->swap(tmp);
174 }