1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
// -*- C++ -*-
// Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the terms
// of the GNU General Public License as published by the Free Software
// Foundation; either version 3, or (at your option) any later
// version.
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file parallel/find_selectors.h
* @brief Function objects representing different tasks to be plugged
* into the parallel find algorithm.
* This file is a GNU parallel extension to the Standard C++ Library.
*/
// Written by Felix Putze.
#ifndef _GLIBCXX_PARALLEL_FIND_SELECTORS_H
#define _GLIBCXX_PARALLEL_FIND_SELECTORS_H 1
#include <parallel/tags.h>
#include <parallel/basic_iterator.h>
#include <bits/stl_pair.h>
namespace __gnu_parallel
{
/** @brief Base class of all __gnu_parallel::find_template selectors. */
struct generic_find_selector
{ };
/**
* @brief Test predicate on a single element, used for std::find()
* and std::find_if ().
*/
struct find_if_selector : public generic_find_selector
{
/** @brief Test on one position.
* @param i1 Iterator on first sequence.
* @param i2 Iterator on second sequence (unused).
* @param pred Find predicate.
*/
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
bool
operator()(RandomAccessIterator1 i1, RandomAccessIterator2 i2, Pred pred)
{ return pred(*i1); }
/** @brief Corresponding sequential algorithm on a sequence.
* @param begin1 Begin iterator of first sequence.
* @param end1 End iterator of first sequence.
* @param begin2 Begin iterator of second sequence.
* @param pred Find predicate.
*/
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
std::pair<RandomAccessIterator1, RandomAccessIterator2>
sequential_algorithm(RandomAccessIterator1 begin1,
RandomAccessIterator1 end1,
RandomAccessIterator2 begin2, Pred pred)
{ return std::make_pair(find_if(begin1, end1, pred,
sequential_tag()), begin2); }
};
/** @brief Test predicate on two adjacent elements. */
struct adjacent_find_selector : public generic_find_selector
{
/** @brief Test on one position.
* @param i1 Iterator on first sequence.
* @param i2 Iterator on second sequence (unused).
* @param pred Find predicate.
*/
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
bool
operator()(RandomAccessIterator1 i1, RandomAccessIterator2 i2, Pred pred)
{
// Passed end iterator is one short.
return pred(*i1, *(i1 + 1));
}
/** @brief Corresponding sequential algorithm on a sequence.
* @param begin1 Begin iterator of first sequence.
* @param end1 End iterator of first sequence.
* @param begin2 Begin iterator of second sequence.
* @param pred Find predicate.
*/
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
std::pair<RandomAccessIterator1, RandomAccessIterator2>
sequential_algorithm(RandomAccessIterator1 begin1,
RandomAccessIterator1 end1,
RandomAccessIterator2 begin2, Pred pred)
{
// Passed end iterator is one short.
RandomAccessIterator1 spot = adjacent_find(begin1, end1 + 1,
pred, sequential_tag());
if (spot == (end1 + 1))
spot = end1;
return std::make_pair(spot, begin2);
}
};
/** @brief Test inverted predicate on a single element. */
struct mismatch_selector : public generic_find_selector
{
/**
* @brief Test on one position.
* @param i1 Iterator on first sequence.
* @param i2 Iterator on second sequence (unused).
* @param pred Find predicate.
*/
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
bool
operator()(RandomAccessIterator1 i1, RandomAccessIterator2 i2, Pred pred)
{ return !pred(*i1, *i2); }
/**
* @brief Corresponding sequential algorithm on a sequence.
* @param begin1 Begin iterator of first sequence.
* @param end1 End iterator of first sequence.
* @param begin2 Begin iterator of second sequence.
* @param pred Find predicate.
*/
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
std::pair<RandomAccessIterator1, RandomAccessIterator2>
sequential_algorithm(RandomAccessIterator1 begin1,
RandomAccessIterator1 end1,
RandomAccessIterator2 begin2, Pred pred)
{ return mismatch(begin1, end1, begin2, pred, sequential_tag()); }
};
/** @brief Test predicate on several elements. */
template<typename ForwardIterator>
struct find_first_of_selector : public generic_find_selector
{
ForwardIterator begin;
ForwardIterator end;
explicit find_first_of_selector(ForwardIterator begin, ForwardIterator end)
: begin(begin), end(end) { }
/** @brief Test on one position.
* @param i1 Iterator on first sequence.
* @param i2 Iterator on second sequence (unused).
* @param pred Find predicate. */
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
bool
operator()(RandomAccessIterator1 i1, RandomAccessIterator2 i2, Pred pred)
{
for (ForwardIterator pos_in_candidates = begin;
pos_in_candidates != end; ++pos_in_candidates)
if (pred(*i1, *pos_in_candidates))
return true;
return false;
}
/** @brief Corresponding sequential algorithm on a sequence.
* @param begin1 Begin iterator of first sequence.
* @param end1 End iterator of first sequence.
* @param begin2 Begin iterator of second sequence.
* @param pred Find predicate. */
template<typename RandomAccessIterator1, typename RandomAccessIterator2,
typename Pred>
std::pair<RandomAccessIterator1, RandomAccessIterator2>
sequential_algorithm(RandomAccessIterator1 begin1,
RandomAccessIterator1 end1,
RandomAccessIterator2 begin2, Pred pred)
{ return std::make_pair(find_first_of(begin1, end1, begin, end, pred,
sequential_tag()), begin2); }
};
}
#endif /* _GLIBCXX_PARALLEL_FIND_SELECTORS_H */
|
