1 // -*- C++ -*-
2
3 // Copyright (C) 2005-2022 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.
10
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.
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
29 // notice appears in all copies, and that both that copyright notice
30 // and this permission notice appear in supporting documentation. None
31 // of the above authors, nor IBM Haifa Research Laboratories, make any
32 // representation about the suitability of this software for any
33 // purpose. It is provided "as is" without express or implied
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
43 PB_DS_CLASS_T_DEC
44 std::pair<
45 typename PB_DS_CLASS_C_DEC::const_iterator,
46 typename PB_DS_CLASS_C_DEC::const_iterator>
47 PB_DS_CLASS_C_DEC::
prefix_range(key_const_reference r_key) const48 prefix_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
54 PB_DS_CLASS_T_DEC
55 std::pair<
56 typename PB_DS_CLASS_C_DEC::iterator,
57 typename PB_DS_CLASS_C_DEC::iterator>
58 PB_DS_CLASS_C_DEC::
prefix_range(key_const_reference r_key)59 prefix_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
65 PB_DS_CLASS_T_DEC
66 std::pair<
67 typename PB_DS_CLASS_C_DEC::const_iterator,
68 typename PB_DS_CLASS_C_DEC::const_iterator>
69 PB_DS_CLASS_C_DEC::
prefix_range(typename access_traits::const_iterator b,typename access_traits::const_iterator e) const70 prefix_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
80 PB_DS_CLASS_T_DEC
81 std::pair<
82 typename PB_DS_CLASS_C_DEC::iterator,
83 typename PB_DS_CLASS_C_DEC::iterator>
84 PB_DS_CLASS_C_DEC::
prefix_range(typename access_traits::const_iterator b,typename access_traits::const_iterator e)85 prefix_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
112 PB_DS_CLASS_T_DEC
113 typename PB_DS_CLASS_C_DEC::node_iterator
114 PB_DS_CLASS_C_DEC::
next_child(node_iterator nd_it,typename access_traits::const_iterator b,typename access_traits::const_iterator e,node_iterator end_nd_it,const access_traits & r_traits)115 next_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
137 PB_DS_CLASS_T_DEC
138 inline void
139 PB_DS_CLASS_C_DEC::
operator ()(node_iterator,node_const_iterator) const140 operator()(node_iterator /*nd_it*/, node_const_iterator /*end_nd_it*/) const
141 { }
142 #endif
143