libstdc++
pat_trie_/erase_fn_imps.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2020 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 pat_trie_/erase_fn_imps.hpp
38  * Contains an implementation class for pat_trie.
39  */
40 
41 #ifdef PB_DS_CLASS_C_DEC
42 
43 PB_DS_CLASS_T_DEC
44 inline bool
45 PB_DS_CLASS_C_DEC::
46 erase(key_const_reference r_key)
47 {
48  node_pointer p_nd = find_imp(r_key);
49  if (p_nd == 0 || p_nd->m_type == i_node)
50  {
51  PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
52  return false;
53  }
54 
55  _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
56  if (!synth_access_traits::equal_keys(PB_DS_V2F(reinterpret_cast<leaf_pointer>(p_nd)->value()), r_key))
57  {
58  PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
59  return false;
60  }
61 
62  PB_DS_CHECK_KEY_EXISTS(r_key)
63  erase_leaf(static_cast<leaf_pointer>(p_nd));
64  PB_DS_ASSERT_VALID((*this))
65  return true;
66 }
67 
68 PB_DS_CLASS_T_DEC
69 void
70 PB_DS_CLASS_C_DEC::
71 erase_fixup(inode_pointer p_nd)
72 {
73  _GLIBCXX_DEBUG_ASSERT(std::distance(p_nd->begin(), p_nd->end()) >= 1);
74  if (std::distance(p_nd->begin(), p_nd->end()) == 1)
75  {
76  node_pointer p_parent = p_nd->m_p_parent;
77  if (p_parent == m_p_head)
78  m_p_head->m_p_parent = *p_nd->begin();
79  else
80  {
81  _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == i_node);
82  node_pointer p_new_child = *p_nd->begin();
83 
84  typedef inode_pointer inode_ptr;
85  inode_ptr p_internal = static_cast<inode_ptr>(p_parent);
86  p_internal->replace_child(p_new_child, pref_begin(p_new_child),
87  pref_end(p_new_child), this);
88  }
89  (*p_nd->begin())->m_p_parent = p_nd->m_p_parent;
90  p_nd->~inode();
91  s_inode_allocator.deallocate(p_nd, 1);
92 
93  if (p_parent == m_p_head)
94  return;
95 
96  _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == i_node);
97  p_nd = static_cast<inode_pointer>(p_parent);
98  }
99 
100  while (true)
101  {
102  _GLIBCXX_DEBUG_ASSERT(std::distance(p_nd->begin(), p_nd->end()) > 1);
103  p_nd->update_prefixes(this);
104  apply_update(p_nd, (node_update*)this);
105  PB_DS_ASSERT_NODE_VALID(p_nd)
106  if (p_nd->m_p_parent->m_type == head_node)
107  return;
108 
109  _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_parent->m_type == i_node);
110 
111  p_nd = static_cast<inode_pointer>(p_nd->m_p_parent);
112  }
113 }
114 
115 PB_DS_CLASS_T_DEC
116 inline void
117 PB_DS_CLASS_C_DEC::
118 actual_erase_leaf(leaf_pointer p_l)
119 {
120  _GLIBCXX_DEBUG_ASSERT(m_size > 0);
121  --m_size;
122  _GLIBCXX_DEBUG_ONLY(debug_base::erase_existing(PB_DS_V2F(p_l->value())));
123  p_l->~leaf();
124  s_leaf_allocator.deallocate(p_l, 1);
125 }
126 
127 PB_DS_CLASS_T_DEC
128 void
129 PB_DS_CLASS_C_DEC::
130 clear()
131 {
132  if (!empty())
133  {
134  clear_imp(m_p_head->m_p_parent);
135  m_size = 0;
136  initialize();
137  _GLIBCXX_DEBUG_ONLY(debug_base::clear();)
138  PB_DS_ASSERT_VALID((*this))
139  }
140 }
141 
142 PB_DS_CLASS_T_DEC
143 void
144 PB_DS_CLASS_C_DEC::
145 clear_imp(node_pointer p_nd)
146 {
147  if (p_nd->m_type == i_node)
148  {
149  _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == i_node);
150  for (typename inode::iterator it =
151  static_cast<inode_pointer>(p_nd)->begin();
152  it != static_cast<inode_pointer>(p_nd)->end();
153  ++it)
154  {
155  node_pointer p_child =* it;
156  clear_imp(p_child);
157  }
158  s_inode_allocator.deallocate(static_cast<inode_pointer>(p_nd), 1);
159  return;
160  }
161 
162  _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
163  static_cast<leaf_pointer>(p_nd)->~leaf();
164  s_leaf_allocator.deallocate(static_cast<leaf_pointer>(p_nd), 1);
165 }
166 
167 PB_DS_CLASS_T_DEC
168 inline typename PB_DS_CLASS_C_DEC::const_iterator
169 PB_DS_CLASS_C_DEC::
170 erase(const_iterator it)
171 {
172  PB_DS_ASSERT_VALID((*this))
173 
174  if (it == end())
175  return it;
176 
177  const_iterator ret_it = it;
178  ++ret_it;
179  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
180  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
181  PB_DS_ASSERT_VALID((*this))
182  return ret_it;
183 }
184 
185 #ifdef PB_DS_DATA_TRUE_INDICATOR
186 PB_DS_CLASS_T_DEC
187 inline typename PB_DS_CLASS_C_DEC::iterator
188 PB_DS_CLASS_C_DEC::
189 erase(iterator it)
190 {
191  PB_DS_ASSERT_VALID((*this))
192 
193  if (it == end())
194  return it;
195  iterator ret_it = it;
196  ++ret_it;
197  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
198  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
199  PB_DS_ASSERT_VALID((*this))
200  return ret_it;
201 }
202 #endif // #ifdef PB_DS_DATA_TRUE_INDICATOR
203 
204 PB_DS_CLASS_T_DEC
205 inline typename PB_DS_CLASS_C_DEC::const_reverse_iterator
206 PB_DS_CLASS_C_DEC::
207 erase(const_reverse_iterator it)
208 {
209  PB_DS_ASSERT_VALID((*this))
210 
211  if (it.m_p_nd == m_p_head)
212  return it;
213  const_reverse_iterator ret_it = it;
214  ++ret_it;
215 
216  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
217  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
218  PB_DS_ASSERT_VALID((*this))
219  return ret_it;
220 }
221 
222 #ifdef PB_DS_DATA_TRUE_INDICATOR
223 PB_DS_CLASS_T_DEC
224 inline typename PB_DS_CLASS_C_DEC::reverse_iterator
225 PB_DS_CLASS_C_DEC::
226 erase(reverse_iterator it)
227 {
228  PB_DS_ASSERT_VALID((*this))
229 
230  if (it.m_p_nd == m_p_head)
231  return it;
232  reverse_iterator ret_it = it;
233  ++ret_it;
234 
235  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
236  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
237  PB_DS_ASSERT_VALID((*this))
238  return ret_it;
239 }
240 #endif // #ifdef PB_DS_DATA_TRUE_INDICATOR
241 
242 PB_DS_CLASS_T_DEC
243 template<typename Pred>
244 inline typename PB_DS_CLASS_C_DEC::size_type
245 PB_DS_CLASS_C_DEC::
246 erase_if(Pred pred)
247 {
248  size_type num_ersd = 0;
249  PB_DS_ASSERT_VALID((*this))
250 
251  iterator it = begin();
252  while (it != end())
253  {
254  PB_DS_ASSERT_VALID((*this))
255  if (pred(*it))
256  {
257  ++num_ersd;
258  it = erase(it);
259  }
260  else
261  ++it;
262  }
263 
264  PB_DS_ASSERT_VALID((*this))
265  return num_ersd;
266 }
267 
268 PB_DS_CLASS_T_DEC
269 void
270 PB_DS_CLASS_C_DEC::
271 erase_leaf(leaf_pointer p_l)
272 {
273  update_min_max_for_erased_leaf(p_l);
274  if (p_l->m_p_parent->m_type == head_node)
275  {
276  _GLIBCXX_DEBUG_ASSERT(size() == 1);
277  clear();
278  return;
279  }
280 
281  _GLIBCXX_DEBUG_ASSERT(size() > 1);
282  _GLIBCXX_DEBUG_ASSERT(p_l->m_p_parent->m_type == i_node);
283 
284  inode_pointer p_parent = static_cast<inode_pointer>(p_l->m_p_parent);
285 
286  p_parent->remove_child(p_l);
287  erase_fixup(p_parent);
288  actual_erase_leaf(p_l);
289 }
290 
291 PB_DS_CLASS_T_DEC
292 void
293 PB_DS_CLASS_C_DEC::
294 update_min_max_for_erased_leaf(leaf_pointer p_l)
295 {
296  if (m_size == 1)
297  {
298  m_p_head->m_p_min = m_p_head;
299  m_p_head->m_p_max = m_p_head;
300  return;
301  }
302 
303  if (p_l == static_cast<leaf_const_pointer>(m_p_head->m_p_min))
304  {
305  iterator it(p_l);
306  ++it;
307  m_p_head->m_p_min = it.m_p_nd;
308  return;
309  }
310 
311  if (p_l == static_cast<leaf_const_pointer>(m_p_head->m_p_max))
312  {
313  iterator it(p_l);
314  --it;
315  m_p_head->m_p_max = it.m_p_nd;
316  }
317 }
318 #endif
std::distance
constexpr iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:138
std::initializer_list::begin
constexpr const _Tp * begin(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to the first element of the initializer_list.
Definition: initializer_list:90
std::initializer_list::end
constexpr const _Tp * end(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to one past the last element of the initializer_list.
Definition: initializer_list:101