libstdc++
prefix_search_node_update_imp.hpp
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1// -*- C++ -*-
2
3// Copyright (C) 2005-2021 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.
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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.
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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.
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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/>.
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25// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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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
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34// warranty.
35
36/**
37 * @file trie_policy/prefix_search_node_update_imp.hpp
38 * Contains an implementation of prefix_search_node_update.
39 */
40
41#ifdef PB_DS_CLASS_C_DEC
42
43PB_DS_CLASS_T_DEC
45 typename PB_DS_CLASS_C_DEC::const_iterator,
46 typename PB_DS_CLASS_C_DEC::const_iterator>
47PB_DS_CLASS_C_DEC::
48prefix_range(key_const_reference r_key) const
49{
50 const access_traits& r_traits = get_access_traits();
51 return (prefix_range(r_traits.begin(r_key), r_traits.end(r_key)));
52}
53
54PB_DS_CLASS_T_DEC
56 typename PB_DS_CLASS_C_DEC::iterator,
57 typename PB_DS_CLASS_C_DEC::iterator>
58PB_DS_CLASS_C_DEC::
59prefix_range(key_const_reference r_key)
60{
61 return (prefix_range(get_access_traits().begin(r_key),
62 get_access_traits().end(r_key)));
63}
64
65PB_DS_CLASS_T_DEC
67 typename PB_DS_CLASS_C_DEC::const_iterator,
68 typename PB_DS_CLASS_C_DEC::const_iterator>
69PB_DS_CLASS_C_DEC::
70prefix_range(typename access_traits::const_iterator b,
71 typename access_traits::const_iterator e) const
72{
73 const std::pair<iterator, iterator> non_const_ret =
74 const_cast<PB_DS_CLASS_C_DEC* >(this)->prefix_range(b, e);
75
76 return (std::make_pair(const_iterator(non_const_ret.first),
77 const_iterator(non_const_ret.second)));
78}
79
80PB_DS_CLASS_T_DEC
82 typename PB_DS_CLASS_C_DEC::iterator,
83 typename PB_DS_CLASS_C_DEC::iterator>
84PB_DS_CLASS_C_DEC::
85prefix_range(typename access_traits::const_iterator b,
86 typename access_traits::const_iterator e)
87{
88 Node_Itr nd_it = node_begin();
89 Node_Itr end_nd_it = node_end();
90
91 const access_traits& r_traits = get_access_traits();
92 const size_type given_range_length = std::distance(b, e);
93
94 while (true)
95 {
96 if (nd_it == end_nd_it)
97 return (std::make_pair(end(), end()));
98
99 const size_type common_range_length =
100 base_type::common_prefix_len(nd_it, b, e, r_traits);
101
102 if (common_range_length >= given_range_length)
103 {
104 iterator ret_b = this->leftmost_it(nd_it);
105 iterator ret_e = this->rightmost_it(nd_it);
106 return (std::make_pair(ret_b, ++ret_e));
107 }
108 nd_it = next_child(nd_it, b, e, end_nd_it, r_traits);
109 }
110}
111
112PB_DS_CLASS_T_DEC
113typename PB_DS_CLASS_C_DEC::node_iterator
114PB_DS_CLASS_C_DEC::
115next_child(node_iterator nd_it, typename access_traits::const_iterator b,
116 typename access_traits::const_iterator e, node_iterator end_nd_it,
117 const access_traits& r_traits)
118{
119 const size_type num_children = nd_it.num_children();
120 node_iterator ret = end_nd_it;
121 size_type max_length = 0;
122 for (size_type i = 0; i < num_children; ++i)
123 {
124 node_iterator pot = nd_it.get_child(i);
125 const size_type common_range_length =
126 base_type::common_prefix_len(pot, b, e, r_traits);
127
128 if (common_range_length > max_length)
129 {
130 ret = pot;
131 max_length = common_range_length;
132 }
133 }
134 return (ret);
135}
136
137PB_DS_CLASS_T_DEC
138inline void
139PB_DS_CLASS_C_DEC::
140operator()(node_iterator /*nd_it*/, node_const_iterator /*end_nd_it*/) const
141{ }
142#endif
_Tp * end(valarray< _Tp > &__va) noexcept
Return an iterator pointing to one past the last element of the valarray.
Definition: valarray:1239
_Tp * begin(valarray< _Tp > &__va) noexcept
Return an iterator pointing to the first element of the valarray.
Definition: valarray:1217
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:213
_T1 first
The first member.
Definition: stl_pair.h:217
_T2 second
The second member.
Definition: stl_pair.h:218