libstdc++
trie_policy/order_statistics_imp.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006, 2009, 2010 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
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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
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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
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24 
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
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35 
36 /**
37  * @file trie_policy/order_statistics_imp.hpp
38  * Contains forward declarations for order_statistics_key
39  */
40 
41 PB_DS_CLASS_T_DEC
42 inline typename PB_DS_CLASS_C_DEC::iterator
43 PB_DS_CLASS_C_DEC::
44 find_by_order(size_type order)
45 {
46  if (empty())
47  return end();
48 
49  ++order;
50  node_iterator nd_it = node_begin();
51 
52  while (true)
53  {
54  if (order > nd_it.get_metadata())
55  return ++base_type::rightmost_it(nd_it);
56 
57  const size_type num_children = nd_it.num_children();
58  if (num_children == 0)
59  return *nd_it;
60 
61  for (size_type i = 0; i < num_children; ++i)
62  {
63  node_iterator child_nd_it = nd_it.get_child(i);
64  if (order <= child_nd_it.get_metadata())
65  {
66  i = num_children;
67  nd_it = child_nd_it;
68  }
69  else
70  order -= child_nd_it.get_metadata();
71  }
72  }
73 }
74 
75 PB_DS_CLASS_T_DEC
76 inline typename PB_DS_CLASS_C_DEC::const_iterator
77 PB_DS_CLASS_C_DEC::
78 find_by_order(size_type order) const
79 { return const_cast<PB_DS_CLASS_C_DEC*>(this)->find_by_order(order); }
80 
81 PB_DS_CLASS_T_DEC
82 inline typename PB_DS_CLASS_C_DEC::size_type
83 PB_DS_CLASS_C_DEC::
84 order_of_key(key_const_reference r_key) const
85 {
86  const _ATraits& r_traits =
87  const_cast<PB_DS_CLASS_C_DEC* >(this)->get_access_traits();
88 
89  return order_of_prefix(r_traits.begin(r_key), r_traits.end(r_key));
90 }
91 
92 PB_DS_CLASS_T_DEC
93 inline typename PB_DS_CLASS_C_DEC::size_type
94 PB_DS_CLASS_C_DEC::
95 order_of_prefix(typename access_traits::const_iterator b,
96  typename access_traits::const_iterator e) const
97 {
98  if (empty())
99  return 0;
100 
101  const _ATraits& r_traits =
102  const_cast<PB_DS_CLASS_C_DEC*>(this)->get_access_traits();
103 
104  node_const_iterator nd_it = node_begin();
105  node_const_iterator end_nd_it = node_end();
106  size_type ord = 0;
107 
108  while (true)
109  {
110  const size_type num_children = nd_it.num_children();
111  if (num_children == 0)
112  {
113  key_const_reference r_key = base_type::extract_key(*(*nd_it));
114  typename access_traits::const_iterator key_b =
115  r_traits.begin(r_key);
116 
117  typename access_traits::const_iterator key_e =
118  r_traits.end(r_key);
119 
120  return (base_type::less(key_b, key_e, b, e, r_traits)) ?
121  ord + 1 : ord;
122  }
123 
124  node_const_iterator next_nd_it = end_nd_it;
125  size_type i = num_children - 1;
126 
127  do
128  {
129  node_const_iterator child_nd_it = nd_it.get_child(i);
130 
131  if (next_nd_it != end_nd_it)
132  ord += child_nd_it.get_metadata();
133  else if (!base_type::less(b, e,
134  child_nd_it.valid_prefix().first,
135  child_nd_it.valid_prefix().second,
136  r_traits))
137  next_nd_it = child_nd_it;
138  }
139  while (i-- > 0);
140 
141  if (next_nd_it == end_nd_it)
142  return ord;
143 
144  nd_it = next_nd_it;
145  }
146 }
147 
148 PB_DS_CLASS_T_DEC
149 inline void
150 PB_DS_CLASS_C_DEC::
151 operator()(node_iterator nd_it, node_const_iterator /*end_nd_it*/) const
152 {
153  const size_type num_children = nd_it.num_children();
154  size_type children_rank = 0;
155  for (size_type i = 0; i < num_children; ++i)
156  children_rank += nd_it.get_child(i).get_metadata();
157 
158  const size_type res = (num_children == 0) ? 1 : children_rank;
159  const_cast<size_type&>(nd_it.get_metadata()) = res;
160 }