libstdc++
experimental/algorithm
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1 // <experimental/algorithm> -*- C++ -*-
2 
3 // Copyright (C) 2014-2017 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
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU 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 /** @file experimental/algorithm
26  * This is a TS C++ Library header.
27  */
28 
29 #ifndef _GLIBCXX_EXPERIMENTAL_ALGORITHM
30 #define _GLIBCXX_EXPERIMENTAL_ALGORITHM 1
31 
32 #pragma GCC system_header
33 
34 #if __cplusplus <= 201103L
35 # include <bits/c++14_warning.h>
36 #else
37 
38 #include <algorithm>
40 
41 namespace std _GLIBCXX_VISIBILITY(default)
42 {
43 namespace experimental
44 {
45 inline namespace fundamentals_v1
46 {
47 _GLIBCXX_BEGIN_NAMESPACE_VERSION
48 
49  template<typename _ForwardIterator, typename _Searcher>
50  inline _ForwardIterator
51  search(_ForwardIterator __first, _ForwardIterator __last,
52  const _Searcher& __searcher)
53  { return __searcher(__first, __last); }
54 
55 #define __cpp_lib_experimental_sample 201402
56 
57  /// Take a random sample from a population.
58  template<typename _PopulationIterator, typename _SampleIterator,
59  typename _Distance, typename _UniformRandomNumberGenerator>
60  _SampleIterator
61  sample(_PopulationIterator __first, _PopulationIterator __last,
62  _SampleIterator __out, _Distance __n,
63  _UniformRandomNumberGenerator&& __g)
64  {
65  using __pop_cat = typename
66  std::iterator_traits<_PopulationIterator>::iterator_category;
67  using __samp_cat = typename
68  std::iterator_traits<_SampleIterator>::iterator_category;
69 
70  static_assert(
71  __or_<is_convertible<__pop_cat, forward_iterator_tag>,
72  is_convertible<__samp_cat, random_access_iterator_tag>>::value,
73  "output range must use a RandomAccessIterator when input range"
74  " does not meet the ForwardIterator requirements");
75 
76  static_assert(is_integral<_Distance>::value,
77  "sample size must be an integer type");
78 
79  typename iterator_traits<_PopulationIterator>::difference_type __d = __n;
80  return std::__sample(__first, __last, __pop_cat{}, __out, __samp_cat{},
81  __d,
82  std::forward<_UniformRandomNumberGenerator>(__g));
83  }
84 
85 _GLIBCXX_END_NAMESPACE_VERSION
86 } // namespace fundamentals_v1
87 } // namespace experimental
88 } // namespace std
89 
90 #endif // C++14
91 
92 #endif // _GLIBCXX_EXPERIMENTAL_ALGORITHM
_RandomAccessIterator __sample(_InputIterator __first, _InputIterator __last, input_iterator_tag, _RandomAccessIterator __out, random_access_iterator_tag, _Size __n, _UniformRandomBitGenerator &&__g)
Reservoir sampling algorithm.
Definition: stl_algo.h:5713
ISO C++ entities toplevel namespace is std.
_SampleIterator sample(_PopulationIterator __first, _PopulationIterator __last, _SampleIterator __out, _Distance __n, _UniformRandomNumberGenerator &&__g)
Take a random sample from a population.
is_integral
Definition: type_traits:328