libstdc++
binary_heap_/insert_fn_imps.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006, 2009, 2011 Free Software Foundation, Inc.
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16 // Under Section 7 of GPL version 3, you are granted additional
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18 // 3.1, as published by the Free Software Foundation.
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25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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28 // is hereby granted without fee, provided that the above copyright
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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 }