libstdc++
checkers.h
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc.
4 //
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9 // version.
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15 
16 // Under Section 7 of GPL version 3, you are granted additional
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18 // 3.1, as published by the Free Software Foundation.
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24 
25 /** @file parallel/checkers.h
26  * @brief Routines for checking the correctness of algorithm results.
27  * This file is a GNU parallel extension to the Standard C++ Library.
28  */
29 
30 // Written by Johannes Singler.
31 
32 #ifndef _GLIBCXX_PARALLEL_CHECKERS_H
33 #define _GLIBCXX_PARALLEL_CHECKERS_H 1
34 
35 #include <functional>
36 #include <cstdio>
37 #include <bits/stl_algobase.h>
38 
39 namespace __gnu_parallel
40 {
41  /**
42  * @brief Check whether @c [begin, @c end) is sorted according to @c comp.
43  * @param begin Begin iterator of sequence.
44  * @param end End iterator of sequence.
45  * @param comp Comparator.
46  * @return @c true if sorted, @c false otherwise.
47  */
48  // XXX Comparator default template argument
49  template<typename InputIterator, typename Comparator>
50  bool
51  is_sorted(InputIterator begin, InputIterator end,
52  Comparator comp
54  value_type>())
55  {
56  if (begin == end)
57  return true;
58 
59  InputIterator current(begin), recent(begin);
60 
61  unsigned long long position = 1;
62  for (current++; current != end; current++)
63  {
64  if (comp(*current, *recent))
65  {
66  printf("is_sorted: check failed before position %i.\n",
67  position);
68  return false;
69  }
70  recent = current;
71  position++;
72  }
73 
74  return true;
75  }
76 
77  /**
78  * @brief Check whether @c [begin, @c end) is sorted according to @c comp.
79  * Prints the position in case an unordered pair is found.
80  * @param begin Begin iterator of sequence.
81  * @param end End iterator of sequence.
82  * @param first_failure The first failure is returned in this variable.
83  * @param comp Comparator.
84  * @return @c true if sorted, @c false otherwise.
85  */
86  // XXX Comparator default template argument
87  template<typename InputIterator, typename Comparator>
88  bool
89  is_sorted_failure(InputIterator begin, InputIterator end,
90  InputIterator& first_failure,
91  Comparator comp
93  value_type>())
94  {
95  if (begin == end)
96  return true;
97 
98  InputIterator current(begin), recent(begin);
99 
100  unsigned long long position = 1;
101  for (current++; current != end; current++)
102  {
103  if (comp(*current, *recent))
104  {
105  first_failure = current;
106  printf("is_sorted: check failed before position %lld.\n",
107  position);
108  return false;
109  }
110  recent = current;
111  position++;
112  }
113 
114  first_failure = end;
115  return true;
116  }
117 
118  /**
119  * @brief Check whether @c [begin, @c end) is sorted according to @c comp.
120  * Prints all unordered pair, including the surrounding two elements.
121  * @param begin Begin iterator of sequence.
122  * @param end End iterator of sequence.
123  * @param comp Comparator.
124  * @return @c true if sorted, @c false otherwise.
125  */
126  template<typename InputIterator, typename Comparator>
127  bool
128  // XXX Comparator default template argument
129  is_sorted_print_failures(InputIterator begin, InputIterator end,
130  Comparator comp
132  <InputIterator>::value_type>())
133  {
134  if (begin == end)
135  return true;
136 
137  InputIterator recent(begin);
138  bool ok = true;
139 
140  for (InputIterator pos(begin + 1); pos != end; pos++)
141  {
142  if (comp(*pos, *recent))
143  {
144  printf("%ld: %d %d %d %d\n", pos - begin, *(pos - 2),
145  *(pos- 1), *pos, *(pos + 1));
146  ok = false;
147  }
148  recent = pos;
149  }
150  return ok;
151  }
152 }
153 
154 #endif /* _GLIBCXX_PARALLEL_CHECKERS_H */
bool is_sorted_failure(InputIterator begin, InputIterator end, InputIterator &first_failure, Comparator comp=std::less< typename std::iterator_traits< InputIterator >::value_type >())
Check whether [begin, end) is sorted according to comp. Prints the position in case an unordered pair...
Definition: checkers.h:89
bool is_sorted(InputIterator begin, InputIterator end, Comparator comp=std::less< typename std::iterator_traits< InputIterator >::value_type >())
Check whether [begin, end) is sorted according to comp.
Definition: checkers.h:51
bool is_sorted_print_failures(InputIterator begin, InputIterator end, Comparator comp=std::less< typename std::iterator_traits< InputIterator >::value_type >())
Check whether [begin, end) is sorted according to comp. Prints all unordered pair, including the surrounding two elements.
Definition: checkers.h:129
One of the comparison functors.
Definition: stl_function.h:226