numeric
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// <numeric> -*- C++ -*-
// Copyright (C) 2001-2018 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/>.
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file include/numeric
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_NUMERIC
#define _GLIBCXX_NUMERIC 1
#pragma GCC system_header
#include <bits/c++config.h>
#include <bits/stl_iterator_base_types.h>
#include <bits/stl_numeric.h>
#ifdef _GLIBCXX_PARALLEL
# include <parallel/numeric>
#endif
/**
* @defgroup numerics Numerics
*
* Components for performing numeric operations. Includes support for
* for complex number types, random number generation, numeric
* (n-at-a-time) arrays, generalized numeric algorithms, and special
* math functions.
*/
#if __cplusplus >= 201402L
#include <type_traits>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
namespace __detail
{
// std::abs is not constexpr and doesn't support unsigned integers.
template<typename _Tp>
constexpr
enable_if_t<__and_<is_integral<_Tp>, is_signed<_Tp>>::value, _Tp>
__abs_integral(_Tp __val)
{ return __val < 0 ? -__val : __val; }
template<typename _Tp>
constexpr
enable_if_t<__and_<is_integral<_Tp>, is_unsigned<_Tp>>::value, _Tp>
__abs_integral(_Tp __val)
{ return __val; }
void __abs_integral(bool) = delete;
template<typename _Mn, typename _Nn>
constexpr common_type_t<_Mn, _Nn>
__gcd(_Mn __m, _Nn __n)
{
return __m == 0 ? __detail::__abs_integral(__n)
: __n == 0 ? __detail::__abs_integral(__m)
: __detail::__gcd(__n, __m % __n);
}
/// Least common multiple
template<typename _Mn, typename _Nn>
constexpr common_type_t<_Mn, _Nn>
__lcm(_Mn __m, _Nn __n)
{
return (__m != 0 && __n != 0)
? (__detail::__abs_integral(__m) / __detail::__gcd(__m, __n))
* __detail::__abs_integral(__n)
: 0;
}
} // namespace __detail
#if __cplusplus > 201402L
#define __cpp_lib_gcd_lcm 201606
// These were used in drafts of SD-6:
#define __cpp_lib_gcd 201606
#define __cpp_lib_lcm 201606
/// Greatest common divisor
template<typename _Mn, typename _Nn>
constexpr common_type_t<_Mn, _Nn>
gcd(_Mn __m, _Nn __n)
{
static_assert(is_integral_v<_Mn>, "gcd arguments are integers");
static_assert(is_integral_v<_Nn>, "gcd arguments are integers");
static_assert(!is_same_v<remove_cv_t<_Mn>, bool>,
"gcd arguments are not bools");
static_assert(!is_same_v<remove_cv_t<_Nn>, bool>,
"gcd arguments are not bools");
return __detail::__gcd(__m, __n);
}
/// Least common multiple
template<typename _Mn, typename _Nn>
constexpr common_type_t<_Mn, _Nn>
lcm(_Mn __m, _Nn __n)
{
static_assert(is_integral_v<_Mn>, "lcm arguments are integers");
static_assert(is_integral_v<_Nn>, "lcm arguments are integers");
static_assert(!is_same_v<remove_cv_t<_Mn>, bool>,
"lcm arguments are not bools");
static_assert(!is_same_v<remove_cv_t<_Nn>, bool>,
"lcm arguments are not bools");
return __detail::__lcm(__m, __n);
}
#endif // C++17
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++14
#endif /* _GLIBCXX_NUMERIC */