File: shuffle.h

package info (click to toggle)
llvm-toolchain-13 1%3A13.0.1-6~deb11u1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 1,418,812 kB
  • sloc: cpp: 5,290,827; ansic: 996,570; asm: 544,593; python: 188,212; objc: 72,027; lisp: 30,291; f90: 25,395; sh: 24,900; javascript: 9,780; pascal: 9,398; perl: 7,484; ml: 5,432; awk: 3,523; makefile: 2,892; xml: 953; cs: 573; fortran: 539
file content (127 lines) | stat: -rw-r--r-- 3,797 bytes parent folder | download | duplicates (4)
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
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP___ALGORITHM_SHUFFLE_H
#define _LIBCPP___ALGORITHM_SHUFFLE_H

#include <__config>
#include <__iterator/iterator_traits.h>
#include <__random/uniform_int_distribution.h>
#include <__utility/swap.h>
#include <cstddef>
#include <cstdint>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

_LIBCPP_BEGIN_NAMESPACE_STD


#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) \
  || defined(_LIBCPP_BUILDING_LIBRARY)
class _LIBCPP_TYPE_VIS __rs_default;

_LIBCPP_FUNC_VIS __rs_default __rs_get();

class _LIBCPP_TYPE_VIS __rs_default
{
    static unsigned __c_;

    __rs_default();
public:
    typedef uint_fast32_t result_type;

    static const result_type _Min = 0;
    static const result_type _Max = 0xFFFFFFFF;

    __rs_default(const __rs_default&);
    ~__rs_default();

    result_type operator()();

    static _LIBCPP_CONSTEXPR result_type min() {return _Min;}
    static _LIBCPP_CONSTEXPR result_type max() {return _Max;}

    friend _LIBCPP_FUNC_VIS __rs_default __rs_get();
};

_LIBCPP_FUNC_VIS __rs_default __rs_get();

template <class _RandomAccessIterator>
_LIBCPP_DEPRECATED_IN_CXX14 void
random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
{
    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
    typedef uniform_int_distribution<ptrdiff_t> _Dp;
    typedef typename _Dp::param_type _Pp;
    difference_type __d = __last - __first;
    if (__d > 1)
    {
        _Dp __uid;
        __rs_default __g = __rs_get();
        for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
        {
            difference_type __i = __uid(__g, _Pp(0, __d));
            if (__i != difference_type(0))
                swap(*__first, *(__first + __i));
        }
    }
}

template <class _RandomAccessIterator, class _RandomNumberGenerator>
_LIBCPP_DEPRECATED_IN_CXX14 void
random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
#ifndef _LIBCPP_CXX03_LANG
               _RandomNumberGenerator&& __rand)
#else
               _RandomNumberGenerator& __rand)
#endif
{
    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
    difference_type __d = __last - __first;
    if (__d > 1)
    {
        for (--__last; __first < __last; ++__first, (void) --__d)
        {
            difference_type __i = __rand(__d);
            if (__i != difference_type(0))
              swap(*__first, *(__first + __i));
        }
    }
}
#endif

template<class _RandomAccessIterator, class _UniformRandomNumberGenerator>
    void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
                 _UniformRandomNumberGenerator&& __g)
{
    typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
    typedef uniform_int_distribution<ptrdiff_t> _Dp;
    typedef typename _Dp::param_type _Pp;
    difference_type __d = __last - __first;
    if (__d > 1)
    {
        _Dp __uid;
        for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
        {
            difference_type __i = __uid(__g, _Pp(0, __d));
            if (__i != difference_type(0))
                swap(*__first, *(__first + __i));
        }
    }
}

_LIBCPP_END_NAMESPACE_STD

_LIBCPP_POP_MACROS

#endif // _LIBCPP___ALGORITHM_SHUFFLE_H