libstdc++
prefix_search_node_update_imp.hpp
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1 // -*- C++ -*-
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3 // Copyright (C) 2005-2017 Free Software Foundation, Inc.
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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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35 
36 /**
37  * @file trie_policy/prefix_search_node_update_imp.hpp
38  * Contains an implementation of prefix_search_node_update.
39  */
40 
41 PB_DS_CLASS_T_DEC
42 std::pair<
43  typename PB_DS_CLASS_C_DEC::const_iterator,
44  typename PB_DS_CLASS_C_DEC::const_iterator>
45 PB_DS_CLASS_C_DEC::
46 prefix_range(key_const_reference r_key) const
47 {
48  const access_traits& r_traits = get_access_traits();
49  return (prefix_range(r_traits.begin(r_key), r_traits.end(r_key)));
50 }
51 
52 PB_DS_CLASS_T_DEC
53 std::pair<
54  typename PB_DS_CLASS_C_DEC::iterator,
55  typename PB_DS_CLASS_C_DEC::iterator>
56 PB_DS_CLASS_C_DEC::
57 prefix_range(key_const_reference r_key)
58 {
59  return (prefix_range(get_access_traits().begin(r_key),
60  get_access_traits().end(r_key)));
61 }
62 
63 PB_DS_CLASS_T_DEC
64 std::pair<
65  typename PB_DS_CLASS_C_DEC::const_iterator,
66  typename PB_DS_CLASS_C_DEC::const_iterator>
67 PB_DS_CLASS_C_DEC::
68 prefix_range(typename access_traits::const_iterator b,
69  typename access_traits::const_iterator e) const
70 {
71  const std::pair<iterator, iterator> non_const_ret =
72  const_cast<PB_DS_CLASS_C_DEC* >(this)->prefix_range(b, e);
73 
74  return (std::make_pair(const_iterator(non_const_ret.first),
75  const_iterator(non_const_ret.second)));
76 }
77 
78 PB_DS_CLASS_T_DEC
79 std::pair<
80  typename PB_DS_CLASS_C_DEC::iterator,
81  typename PB_DS_CLASS_C_DEC::iterator>
82 PB_DS_CLASS_C_DEC::
83 prefix_range(typename access_traits::const_iterator b,
84  typename access_traits::const_iterator e)
85 {
86  Node_Itr nd_it = node_begin();
87  Node_Itr end_nd_it = node_end();
88 
89  const access_traits& r_traits = get_access_traits();
90  const size_type given_range_length = std::distance(b, e);
91 
92  while (true)
93  {
94  if (nd_it == end_nd_it)
95  return (std::make_pair(end(), end()));
96 
97  const size_type common_range_length =
98  base_type::common_prefix_len(nd_it, b, e, r_traits);
99 
100  if (common_range_length >= given_range_length)
101  {
102  iterator ret_b = this->leftmost_it(nd_it);
103  iterator ret_e = this->rightmost_it(nd_it);
104  return (std::make_pair(ret_b, ++ret_e));
105  }
106  nd_it = next_child(nd_it, b, e, end_nd_it, r_traits);
107  }
108 }
109 
110 PB_DS_CLASS_T_DEC
111 typename PB_DS_CLASS_C_DEC::node_iterator
112 PB_DS_CLASS_C_DEC::
113 next_child(node_iterator nd_it, typename access_traits::const_iterator b,
114  typename access_traits::const_iterator e, node_iterator end_nd_it,
115  const access_traits& r_traits)
116 {
117  const size_type num_children = nd_it.num_children();
118  node_iterator ret = end_nd_it;
119  size_type max_length = 0;
120  for (size_type i = 0; i < num_children; ++i)
121  {
122  node_iterator pot = nd_it.get_child(i);
123  const size_type common_range_length =
124  base_type::common_prefix_len(pot, b, e, r_traits);
125 
126  if (common_range_length > max_length)
127  {
128  ret = pot;
129  max_length = common_range_length;
130  }
131  }
132  return (ret);
133 }
134 
135 PB_DS_CLASS_T_DEC
136 inline void
137 PB_DS_CLASS_C_DEC::
138 operator()(node_iterator /*nd_it*/, node_const_iterator /*end_nd_it*/) const
139 { }
_T2 second
first is a copy of the first object
Definition: stl_pair.h:204
constexpr const _Tp * begin(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to the first element of the initializer_list.
_T1 first
second_type is the second bound type
Definition: stl_pair.h:203
constexpr const _Tp * end(initializer_list< _Tp > __ils) noexcept
Return an iterator pointing to one past the last element of the initializer_list. ...
constexpr pair< typename __decay_and_strip< _T1 >::__type, typename __decay_and_strip< _T2 >::__type > make_pair(_T1 &&__x, _T2 &&__y)
A convenience wrapper for creating a pair from two objects.
Definition: stl_pair.h:519
_GLIBCXX17_CONSTEXPR iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:198