libstdc++
binary_heap_/erase_fn_imps.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2018 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.
10 
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.
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
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35 
36 /**
37  * @file binary_heap_/erase_fn_imps.hpp
38  * Contains an implementation class for a binary_heap.
39  */
40 
41 PB_DS_CLASS_T_DEC
42 void
43 PB_DS_CLASS_C_DEC::
44 clear()
45 {
46  for (size_type i = 0; i < m_size; ++i)
47  erase_at(m_a_entries, i, s_no_throw_copies_ind);
48 
49  __try
50  {
51  const size_type new_size = resize_policy::get_new_size_for_arbitrary(0);
52  entry_pointer new_entries = s_entry_allocator.allocate(new_size);
53  resize_policy::notify_arbitrary(new_size);
54  s_entry_allocator.deallocate(m_a_entries, m_actual_size);
55  m_actual_size = new_size;
56  m_a_entries = new_entries;
57  }
58  __catch(...)
59  { }
60 
61  m_size = 0;
62  PB_DS_ASSERT_VALID((*this))
63 }
64 
65 PB_DS_CLASS_T_DEC
66 void
67 PB_DS_CLASS_C_DEC::
68 erase_at(entry_pointer a_entries, size_type i, false_type)
69 {
70  a_entries[i]->~value_type();
71  s_value_allocator.deallocate(a_entries[i], 1);
72 }
73 
74 PB_DS_CLASS_T_DEC
75 void
76 PB_DS_CLASS_C_DEC::
77 erase_at(entry_pointer, size_type, true_type)
78 { }
79 
80 PB_DS_CLASS_T_DEC
81 inline void
82 PB_DS_CLASS_C_DEC::
83 pop()
84 {
85  PB_DS_ASSERT_VALID((*this))
86  _GLIBCXX_DEBUG_ASSERT(!empty());
87 
88  pop_heap();
89  erase_at(m_a_entries, m_size - 1, s_no_throw_copies_ind);
90  resize_for_erase_if_needed();
91  _GLIBCXX_DEBUG_ASSERT(m_size > 0);
92  --m_size;
93 
94  PB_DS_ASSERT_VALID((*this))
95 }
96 
97 PB_DS_CLASS_T_DEC
98 template<typename Pred>
99 typename PB_DS_CLASS_C_DEC::size_type
100 PB_DS_CLASS_C_DEC::
101 erase_if(Pred pred)
102 {
103  PB_DS_ASSERT_VALID((*this))
104 
105  typedef typename entry_pred<value_type, Pred, _Alloc, simple_value>::type
106  pred_t;
107 
108  const size_type left = partition(pred_t(pred));
109  _GLIBCXX_DEBUG_ASSERT(m_size >= left);
110  const size_type ersd = m_size - left;
111  for (size_type i = left; i < m_size; ++i)
112  erase_at(m_a_entries, i, s_no_throw_copies_ind);
113 
114  __try
115  {
116  const size_type new_size =
117  resize_policy::get_new_size_for_arbitrary(left);
118 
119  entry_pointer new_entries = s_entry_allocator.allocate(new_size);
120  std::copy(m_a_entries, m_a_entries + left, new_entries);
121  s_entry_allocator.deallocate(m_a_entries, m_actual_size);
122  m_actual_size = new_size;
123  resize_policy::notify_arbitrary(m_actual_size);
124  }
125  __catch(...)
126  { };
127 
128  m_size = left;
129  make_heap();
130  PB_DS_ASSERT_VALID((*this))
131  return ersd;
132 }
133 
134 PB_DS_CLASS_T_DEC
135 inline void
136 PB_DS_CLASS_C_DEC::
137 erase(point_iterator it)
138 {
139  PB_DS_ASSERT_VALID((*this))
140  _GLIBCXX_DEBUG_ASSERT(!empty());
141 
142  const size_type fix_pos = it.m_p_e - m_a_entries;
143  std::swap(*it.m_p_e, m_a_entries[m_size - 1]);
144  erase_at(m_a_entries, m_size - 1, s_no_throw_copies_ind);
145  resize_for_erase_if_needed();
146 
147  _GLIBCXX_DEBUG_ASSERT(m_size > 0);
148  --m_size;
149  _GLIBCXX_DEBUG_ASSERT(fix_pos <= m_size);
150 
151  if (fix_pos != m_size)
152  fix(m_a_entries + fix_pos);
153 
154  PB_DS_ASSERT_VALID((*this))
155 }
156 
157 PB_DS_CLASS_T_DEC
158 inline void
159 PB_DS_CLASS_C_DEC::
160 resize_for_erase_if_needed()
161 {
162  if (!resize_policy::resize_needed_for_shrink(m_size))
163  return;
164 
165  __try
166  {
167  const size_type new_size = resize_policy::get_new_size_for_shrink();
168  entry_pointer new_entries = s_entry_allocator.allocate(new_size);
169  resize_policy::notify_shrink_resize();
170 
171  _GLIBCXX_DEBUG_ASSERT(m_size > 0);
172  std::copy(m_a_entries, m_a_entries + m_size - 1, new_entries);
173  s_entry_allocator.deallocate(m_a_entries, m_actual_size);
174  m_actual_size = new_size;
175  m_a_entries = new_entries;
176  }
177  __catch(...)
178  { }
179 }
180 
181 PB_DS_CLASS_T_DEC
182 template<typename Pred>
183 typename PB_DS_CLASS_C_DEC::size_type
184 PB_DS_CLASS_C_DEC::
185 partition(Pred pred)
186 {
187  size_type left = 0;
188  size_type right = m_size - 1;
189 
190  while (right + 1 != left)
191  {
192  _GLIBCXX_DEBUG_ASSERT(left <= m_size);
193 
194  if (!pred(m_a_entries[left]))
195  ++left;
196  else if (pred(m_a_entries[right]))
197  --right;
198  else
199  {
200  _GLIBCXX_DEBUG_ASSERT(left < right);
201  std::swap(m_a_entries[left], m_a_entries[right]);
202  ++left;
203  --right;
204  }
205  }
206 
207  return left;
208 }
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:75
ISO C++ entities toplevel namespace is std.
ios_base & right(ios_base &__base)
Calls base.setf(ios_base::right, ios_base::adjustfield).
Definition: ios_base.h:1009
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:78
ios_base & left(ios_base &__base)
Calls base.setf(ios_base::left, ios_base::adjustfield).
Definition: ios_base.h:1001