mirror of
https://github.com/yuzu-emu/ext-boost.git
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581 lines
22 KiB
C++
581 lines
22 KiB
C++
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// (C) Copyright Jeremy William Murphy 2016.
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// Use, modification and distribution are subject to the
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// Boost Software License, Version 1.0. (See accompanying file
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// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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#ifndef BOOST_INTEGER_COMMON_FACTOR_RT_HPP
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#define BOOST_INTEGER_COMMON_FACTOR_RT_HPP
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#include <boost/assert.hpp>
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#include <boost/core/enable_if.hpp>
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#include <boost/config.hpp> // for BOOST_NESTED_TEMPLATE, etc.
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#include <boost/limits.hpp> // for std::numeric_limits
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#include <climits> // for CHAR_MIN
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#include <boost/detail/workaround.hpp>
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#include <iterator>
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#include <algorithm>
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#include <limits>
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#ifndef BOOST_NO_CXX11_HDR_TYPE_TRAITS
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#include <type_traits>
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#endif
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#ifdef BOOST_NO_CXX11_HDR_FUNCTIONAL
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#include <functional>
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#endif
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#if ((defined(BOOST_MSVC) && (BOOST_MSVC >= 1600)) || (defined(__clang__) && defined(__c2__)) || (defined(BOOST_INTEL) && defined(_MSC_VER))) && (defined(_M_IX86) || defined(_M_X64))
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#include <intrin.h>
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#endif
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#ifdef BOOST_MSVC
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#pragma warning(push)
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#pragma warning(disable:4127 4244) // Conditional expression is constant
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#endif
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#if !defined(BOOST_NO_CXX11_HDR_TYPE_TRAITS) && !defined(BOOST_NO_CXX11_NOEXCEPT)
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#define BOOST_GCD_NOEXCEPT(T) noexcept(std::is_arithmetic<T>::value)
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#else
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#define BOOST_GCD_NOEXCEPT(T)
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#endif
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namespace boost {
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template <class I>
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class rational;
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namespace integer {
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namespace gcd_detail{
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//
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// some helper functions which really should be constexpr already, but sadly aren't:
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//
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#ifndef BOOST_NO_CXX14_CONSTEXPR
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template <class T>
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inline constexpr T constexpr_min(T const& a, T const& b) BOOST_GCD_NOEXCEPT(T)
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{
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return a < b ? a : b;
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}
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template <class T>
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inline constexpr auto constexpr_swap(T&a, T& b) BOOST_GCD_NOEXCEPT(T) -> decltype(a.swap(b))
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{
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return a.swap(b);
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}
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template <class T, class U>
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inline constexpr void constexpr_swap(T&a, U& b...) BOOST_GCD_NOEXCEPT(T)
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{
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T t(static_cast<T&&>(a));
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a = static_cast<T&&>(b);
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b = static_cast<T&&>(t);
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}
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#else
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template <class T>
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inline T constexpr_min(T const& a, T const& b) BOOST_GCD_NOEXCEPT(T)
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{
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return a < b ? a : b;
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}
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template <class T>
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inline void constexpr_swap(T&a, T& b) BOOST_GCD_NOEXCEPT(T)
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{
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using std::swap;
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swap(a, b);
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}
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#endif
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template <class T, bool a =
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#ifndef BOOST_NO_CXX11_HDR_TYPE_TRAITS
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std::is_unsigned<T>::value ||
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#endif
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(std::numeric_limits<T>::is_specialized && !std::numeric_limits<T>::is_signed)>
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struct gcd_traits_abs_defaults
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{
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inline static BOOST_CXX14_CONSTEXPR const T& abs(const T& val) BOOST_GCD_NOEXCEPT(T) { return val; }
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};
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template <class T>
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struct gcd_traits_abs_defaults<T, false>
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{
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inline static T BOOST_CXX14_CONSTEXPR abs(const T& val) BOOST_GCD_NOEXCEPT(T)
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{
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// This sucks, but std::abs is not constexpr :(
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return val < T(0) ? -val : val;
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}
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};
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enum method_type
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{
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method_euclid = 0,
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method_binary = 1,
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method_mixed = 2
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};
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struct any_convert
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{
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template <class T>
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any_convert(const T&);
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};
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struct unlikely_size
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{
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char buf[9973];
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};
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unlikely_size operator <<= (any_convert, any_convert);
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unlikely_size operator >>= (any_convert, any_convert);
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template <class T>
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struct gcd_traits_defaults : public gcd_traits_abs_defaults<T>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(T& val) BOOST_GCD_NOEXCEPT(T)
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{
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unsigned r = 0;
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while(0 == (val & 1u))
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{
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#ifdef _MSC_VER // VC++ can't handle operator >>= in constexpr code for some reason
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val = val >> 1;
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#else
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val >>= 1;
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#endif
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++r;
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}
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return r;
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}
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inline static BOOST_CXX14_CONSTEXPR bool less(const T& a, const T& b) BOOST_GCD_NOEXCEPT(T)
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{
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return a < b;
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}
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static T& get_value();
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#ifndef BOOST_NO_SFINAE
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static const bool has_operator_left_shift_equal = sizeof(get_value() <<= 2) != sizeof(unlikely_size);
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static const bool has_operator_right_shift_equal = sizeof(get_value() >>= 2) != sizeof(unlikely_size);
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#else
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static const bool has_operator_left_shift_equal = true;
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static const bool has_operator_right_shift_equal = true;
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#endif
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static const method_type method = std::numeric_limits<T>::is_specialized && std::numeric_limits<T>::is_integer && has_operator_left_shift_equal && has_operator_right_shift_equal ? method_mixed : method_euclid;
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};
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//
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// Default gcd_traits just inherits from defaults:
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//
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template <class T>
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struct gcd_traits : public gcd_traits_defaults<T> {};
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//
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// Some platforms have fast bitscan operations, that allow us to implement
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// make_odd much more efficiently, unfortunately we can't use these if we want
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// the functions to be constexpr as the compiler intrinsics aren't constexpr.
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//
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#if defined(BOOST_NO_CXX14_CONSTEXPR) && ((defined(BOOST_MSVC) && (BOOST_MSVC >= 1600)) || (defined(__clang__) && defined(__c2__)) || (defined(BOOST_INTEL) && defined(_MSC_VER))) && (defined(_M_IX86) || defined(_M_X64))
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#pragma intrinsic(_BitScanForward,)
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template <>
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struct gcd_traits<unsigned long> : public gcd_traits_defaults<unsigned long>
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{
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BOOST_FORCEINLINE static unsigned find_lsb(unsigned long val) BOOST_NOEXCEPT
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{
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unsigned long result;
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_BitScanForward(&result, val);
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return result;
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}
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BOOST_FORCEINLINE static unsigned make_odd(unsigned long& val) BOOST_NOEXCEPT
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{
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unsigned result = find_lsb(val);
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val >>= result;
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return result;
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}
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};
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#ifdef _M_X64
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#pragma intrinsic(_BitScanForward64)
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template <>
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struct gcd_traits<unsigned __int64> : public gcd_traits_defaults<unsigned __int64>
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{
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BOOST_FORCEINLINE static unsigned find_lsb(unsigned __int64 mask) BOOST_NOEXCEPT
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{
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unsigned long result;
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_BitScanForward64(&result, mask);
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return result;
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}
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BOOST_FORCEINLINE static unsigned make_odd(unsigned __int64& val) BOOST_NOEXCEPT
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{
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unsigned result = find_lsb(val);
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val >>= result;
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return result;
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}
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};
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#endif
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//
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// Other integer type are trivial adaptations of the above,
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// this works for signed types too, as by the time these functions
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// are called, all values are > 0.
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//
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template <> struct gcd_traits<long> : public gcd_traits_defaults<long>
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{ BOOST_FORCEINLINE static unsigned make_odd(long& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<unsigned int> : public gcd_traits_defaults<unsigned int>
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{ BOOST_FORCEINLINE static unsigned make_odd(unsigned int& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<int> : public gcd_traits_defaults<int>
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{ BOOST_FORCEINLINE static unsigned make_odd(int& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<unsigned short> : public gcd_traits_defaults<unsigned short>
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{ BOOST_FORCEINLINE static unsigned make_odd(unsigned short& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<short> : public gcd_traits_defaults<short>
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{ BOOST_FORCEINLINE static unsigned make_odd(short& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<unsigned char> : public gcd_traits_defaults<unsigned char>
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{ BOOST_FORCEINLINE static unsigned make_odd(unsigned char& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<signed char> : public gcd_traits_defaults<signed char>
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{ BOOST_FORCEINLINE static unsigned make_odd(signed char& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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template <> struct gcd_traits<char> : public gcd_traits_defaults<char>
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{ BOOST_FORCEINLINE static unsigned make_odd(char& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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#ifndef BOOST_NO_INTRINSIC_WCHAR_T
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template <> struct gcd_traits<wchar_t> : public gcd_traits_defaults<wchar_t>
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{ BOOST_FORCEINLINE static unsigned make_odd(wchar_t& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; } };
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#endif
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#ifdef _M_X64
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template <> struct gcd_traits<__int64> : public gcd_traits_defaults<__int64>
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{ BOOST_FORCEINLINE static unsigned make_odd(__int64& val)BOOST_NOEXCEPT{ unsigned result = gcd_traits<unsigned __int64>::find_lsb(val); val >>= result; return result; } };
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#endif
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#elif defined(BOOST_GCC) || defined(__clang__) || (defined(BOOST_INTEL) && defined(__GNUC__))
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template <>
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struct gcd_traits<unsigned> : public gcd_traits_defaults<unsigned>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned find_lsb(unsigned mask)BOOST_NOEXCEPT
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{
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return __builtin_ctz(mask);
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}
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(unsigned& val)BOOST_NOEXCEPT
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{
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unsigned result = find_lsb(val);
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val >>= result;
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return result;
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}
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};
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template <>
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struct gcd_traits<unsigned long> : public gcd_traits_defaults<unsigned long>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned find_lsb(unsigned long mask)BOOST_NOEXCEPT
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{
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return __builtin_ctzl(mask);
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}
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(unsigned long& val)BOOST_NOEXCEPT
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{
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unsigned result = find_lsb(val);
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val >>= result;
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return result;
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}
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};
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template <>
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struct gcd_traits<boost::ulong_long_type> : public gcd_traits_defaults<boost::ulong_long_type>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned find_lsb(boost::ulong_long_type mask)BOOST_NOEXCEPT
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{
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return __builtin_ctzll(mask);
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}
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(boost::ulong_long_type& val)BOOST_NOEXCEPT
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{
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unsigned result = find_lsb(val);
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val >>= result;
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return result;
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}
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};
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//
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// Other integer type are trivial adaptations of the above,
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// this works for signed types too, as by the time these functions
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// are called, all values are > 0.
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//
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template <> struct gcd_traits<boost::long_long_type> : public gcd_traits_defaults<boost::long_long_type>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(boost::long_long_type& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<boost::ulong_long_type>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<long> : public gcd_traits_defaults<long>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(long& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<int> : public gcd_traits_defaults<int>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(int& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned long>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<unsigned short> : public gcd_traits_defaults<unsigned short>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(unsigned short& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<short> : public gcd_traits_defaults<short>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(short& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<unsigned char> : public gcd_traits_defaults<unsigned char>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(unsigned char& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<signed char> : public gcd_traits_defaults<signed char>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(signed char& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned>::find_lsb(val); val >>= result; return result; }
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};
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template <> struct gcd_traits<char> : public gcd_traits_defaults<char>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(char& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned>::find_lsb(val); val >>= result; return result; }
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};
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#ifndef BOOST_NO_INTRINSIC_WCHAR_T
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template <> struct gcd_traits<wchar_t> : public gcd_traits_defaults<wchar_t>
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{
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BOOST_FORCEINLINE static BOOST_CXX14_CONSTEXPR unsigned make_odd(wchar_t& val)BOOST_NOEXCEPT { unsigned result = gcd_traits<unsigned>::find_lsb(val); val >>= result; return result; }
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};
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#endif
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#endif
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//
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// The Mixed Binary Euclid Algorithm
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// Sidi Mohamed Sedjelmaci
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// Electronic Notes in Discrete Mathematics 35 (2009) 169-176
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//
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template <class T>
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BOOST_CXX14_CONSTEXPR T mixed_binary_gcd(T u, T v) BOOST_GCD_NOEXCEPT(T)
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{
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if(gcd_traits<T>::less(u, v))
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constexpr_swap(u, v);
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unsigned shifts = 0;
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if(u == T(0))
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return v;
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if(v == T(0))
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return u;
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shifts = constexpr_min(gcd_traits<T>::make_odd(u), gcd_traits<T>::make_odd(v));
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while(gcd_traits<T>::less(1, v))
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{
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u %= v;
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v -= u;
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if(u == T(0))
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return v << shifts;
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if(v == T(0))
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return u << shifts;
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gcd_traits<T>::make_odd(u);
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gcd_traits<T>::make_odd(v);
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if(gcd_traits<T>::less(u, v))
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constexpr_swap(u, v);
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}
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return (v == 1 ? v : u) << shifts;
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}
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/** Stein gcd (aka 'binary gcd')
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*
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* From Mathematics to Generic Programming, Alexander Stepanov, Daniel Rose
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*/
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template <typename SteinDomain>
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BOOST_CXX14_CONSTEXPR SteinDomain Stein_gcd(SteinDomain m, SteinDomain n) BOOST_GCD_NOEXCEPT(SteinDomain)
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{
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BOOST_ASSERT(m >= 0);
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BOOST_ASSERT(n >= 0);
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if (m == SteinDomain(0))
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return n;
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||
|
if (n == SteinDomain(0))
|
||
|
return m;
|
||
|
// m > 0 && n > 0
|
||
|
unsigned d_m = gcd_traits<SteinDomain>::make_odd(m);
|
||
|
unsigned d_n = gcd_traits<SteinDomain>::make_odd(n);
|
||
|
// odd(m) && odd(n)
|
||
|
while (m != n)
|
||
|
{
|
||
|
if (n > m)
|
||
|
constexpr_swap(n, m);
|
||
|
m -= n;
|
||
|
gcd_traits<SteinDomain>::make_odd(m);
|
||
|
}
|
||
|
// m == n
|
||
|
m <<= constexpr_min(d_m, d_n);
|
||
|
return m;
|
||
|
}
|
||
|
|
||
|
|
||
|
/** Euclidean algorithm
|
||
|
*
|
||
|
* From Mathematics to Generic Programming, Alexander Stepanov, Daniel Rose
|
||
|
*
|
||
|
*/
|
||
|
template <typename EuclideanDomain>
|
||
|
inline BOOST_CXX14_CONSTEXPR EuclideanDomain Euclid_gcd(EuclideanDomain a, EuclideanDomain b) BOOST_GCD_NOEXCEPT(EuclideanDomain)
|
||
|
{
|
||
|
while (b != EuclideanDomain(0))
|
||
|
{
|
||
|
a %= b;
|
||
|
constexpr_swap(a, b);
|
||
|
}
|
||
|
return a;
|
||
|
}
|
||
|
|
||
|
|
||
|
template <typename T>
|
||
|
inline BOOST_CXX14_CONSTEXPR BOOST_DEDUCED_TYPENAME enable_if_c<gcd_traits<T>::method == method_mixed, T>::type
|
||
|
optimal_gcd_select(T const &a, T const &b) BOOST_GCD_NOEXCEPT(T)
|
||
|
{
|
||
|
return gcd_detail::mixed_binary_gcd(a, b);
|
||
|
}
|
||
|
|
||
|
template <typename T>
|
||
|
inline BOOST_CXX14_CONSTEXPR BOOST_DEDUCED_TYPENAME enable_if_c<gcd_traits<T>::method == method_binary, T>::type
|
||
|
optimal_gcd_select(T const &a, T const &b) BOOST_GCD_NOEXCEPT(T)
|
||
|
{
|
||
|
return gcd_detail::Stein_gcd(a, b);
|
||
|
}
|
||
|
|
||
|
template <typename T>
|
||
|
inline BOOST_CXX14_CONSTEXPR BOOST_DEDUCED_TYPENAME enable_if_c<gcd_traits<T>::method == method_euclid, T>::type
|
||
|
optimal_gcd_select(T const &a, T const &b) BOOST_GCD_NOEXCEPT(T)
|
||
|
{
|
||
|
return gcd_detail::Euclid_gcd(a, b);
|
||
|
}
|
||
|
|
||
|
template <class T>
|
||
|
inline BOOST_CXX14_CONSTEXPR T lcm_imp(const T& a, const T& b) BOOST_GCD_NOEXCEPT(T)
|
||
|
{
|
||
|
T temp = boost::integer::gcd_detail::optimal_gcd_select(a, b);
|
||
|
#if BOOST_WORKAROUND(BOOST_GCC_VERSION, < 40500)
|
||
|
return (temp != T(0)) ? T(a / temp * b) : T(0);
|
||
|
#else
|
||
|
return temp != T(0) ? T(a / temp * b) : T(0);
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
} // namespace detail
|
||
|
|
||
|
|
||
|
template <typename Integer>
|
||
|
inline BOOST_CXX14_CONSTEXPR Integer gcd(Integer const &a, Integer const &b) BOOST_GCD_NOEXCEPT(Integer)
|
||
|
{
|
||
|
if(a == (std::numeric_limits<Integer>::min)())
|
||
|
return a == static_cast<Integer>(0) ? gcd_detail::gcd_traits<Integer>::abs(b) : boost::integer::gcd(static_cast<Integer>(a % b), b);
|
||
|
else if (b == (std::numeric_limits<Integer>::min)())
|
||
|
return b == static_cast<Integer>(0) ? gcd_detail::gcd_traits<Integer>::abs(a) : boost::integer::gcd(a, static_cast<Integer>(b % a));
|
||
|
return gcd_detail::optimal_gcd_select(static_cast<Integer>(gcd_detail::gcd_traits<Integer>::abs(a)), static_cast<Integer>(gcd_detail::gcd_traits<Integer>::abs(b)));
|
||
|
}
|
||
|
|
||
|
template <typename Integer>
|
||
|
inline BOOST_CXX14_CONSTEXPR Integer lcm(Integer const &a, Integer const &b) BOOST_GCD_NOEXCEPT(Integer)
|
||
|
{
|
||
|
return gcd_detail::lcm_imp(static_cast<Integer>(gcd_detail::gcd_traits<Integer>::abs(a)), static_cast<Integer>(gcd_detail::gcd_traits<Integer>::abs(b)));
|
||
|
}
|
||
|
#ifndef BOOST_NO_CXX11_VARIADIC_TEMPLATES
|
||
|
//
|
||
|
// This looks slightly odd, but the variadic forms must have 3 or more arguments, and the variadic argument pack may be empty.
|
||
|
// This matters not at all for most compilers, but Oracle C++ selects the wrong overload in the 2-arg case unless we do this.
|
||
|
//
|
||
|
template <typename Integer, typename... Args>
|
||
|
inline BOOST_CXX14_CONSTEXPR Integer gcd(Integer const &a, Integer const &b, const Integer& c, Args const&... args) BOOST_GCD_NOEXCEPT(Integer)
|
||
|
{
|
||
|
Integer t = gcd(b, c, args...);
|
||
|
return t == 1 ? 1 : gcd(a, t);
|
||
|
}
|
||
|
|
||
|
template <typename Integer, typename... Args>
|
||
|
inline BOOST_CXX14_CONSTEXPR Integer lcm(Integer const &a, Integer const &b, Integer const& c, Args const&... args) BOOST_GCD_NOEXCEPT(Integer)
|
||
|
{
|
||
|
return lcm(a, lcm(b, c, args...));
|
||
|
}
|
||
|
#endif
|
||
|
//
|
||
|
// Special handling for rationals:
|
||
|
//
|
||
|
template <typename Integer>
|
||
|
inline typename boost::enable_if_c<std::numeric_limits<Integer>::is_specialized, boost::rational<Integer> >::type gcd(boost::rational<Integer> const &a, boost::rational<Integer> const &b)
|
||
|
{
|
||
|
return boost::rational<Integer>(static_cast<Integer>(gcd(a.numerator(), b.numerator())), static_cast<Integer>(lcm(a.denominator(), b.denominator())));
|
||
|
}
|
||
|
|
||
|
template <typename Integer>
|
||
|
inline typename boost::enable_if_c<std::numeric_limits<Integer>::is_specialized, boost::rational<Integer> >::type lcm(boost::rational<Integer> const &a, boost::rational<Integer> const &b)
|
||
|
{
|
||
|
return boost::rational<Integer>(static_cast<Integer>(lcm(a.numerator(), b.numerator())), static_cast<Integer>(gcd(a.denominator(), b.denominator())));
|
||
|
}
|
||
|
/**
|
||
|
* Knuth, The Art of Computer Programming: Volume 2, Third edition, 1998
|
||
|
* Chapter 4.5.2, Algorithm C: Greatest common divisor of n integers.
|
||
|
*
|
||
|
* Knuth counts down from n to zero but we naturally go from first to last.
|
||
|
* We also return the termination position because it might be useful to know.
|
||
|
*
|
||
|
* Partly by quirk, partly by design, this algorithm is defined for n = 1,
|
||
|
* because the gcd of {x} is x. It is not defined for n = 0.
|
||
|
*
|
||
|
* @tparam I Input iterator.
|
||
|
* @return The gcd of the range and the iterator position at termination.
|
||
|
*/
|
||
|
template <typename I>
|
||
|
std::pair<typename std::iterator_traits<I>::value_type, I>
|
||
|
gcd_range(I first, I last) BOOST_GCD_NOEXCEPT(I)
|
||
|
{
|
||
|
BOOST_ASSERT(first != last);
|
||
|
typedef typename std::iterator_traits<I>::value_type T;
|
||
|
|
||
|
T d = *first;
|
||
|
++first;
|
||
|
while (d != T(1) && first != last)
|
||
|
{
|
||
|
d = gcd(d, *first);
|
||
|
++first;
|
||
|
}
|
||
|
return std::make_pair(d, first);
|
||
|
}
|
||
|
template <typename I>
|
||
|
std::pair<typename std::iterator_traits<I>::value_type, I>
|
||
|
lcm_range(I first, I last) BOOST_GCD_NOEXCEPT(I)
|
||
|
{
|
||
|
BOOST_ASSERT(first != last);
|
||
|
typedef typename std::iterator_traits<I>::value_type T;
|
||
|
|
||
|
T d = *first;
|
||
|
++first;
|
||
|
while (d != T(0) && first != last)
|
||
|
{
|
||
|
d = lcm(d, *first);
|
||
|
++first;
|
||
|
}
|
||
|
return std::make_pair(d, first);
|
||
|
}
|
||
|
|
||
|
template < typename IntegerType >
|
||
|
class gcd_evaluator
|
||
|
#ifdef BOOST_NO_CXX11_HDR_FUNCTIONAL
|
||
|
: public std::binary_function<IntegerType, IntegerType, IntegerType>
|
||
|
#endif
|
||
|
{
|
||
|
public:
|
||
|
#ifndef BOOST_NO_CXX11_HDR_FUNCTIONAL
|
||
|
typedef IntegerType first_argument_type;
|
||
|
typedef IntegerType second_argument_type;
|
||
|
typedef IntegerType result_type;
|
||
|
#endif
|
||
|
IntegerType operator()(IntegerType const &a, IntegerType const &b) const
|
||
|
{
|
||
|
return boost::integer::gcd(a, b);
|
||
|
}
|
||
|
};
|
||
|
|
||
|
template < typename IntegerType >
|
||
|
class lcm_evaluator
|
||
|
#ifdef BOOST_NO_CXX11_HDR_FUNCTIONAL
|
||
|
: public std::binary_function<IntegerType, IntegerType, IntegerType>
|
||
|
#endif
|
||
|
{
|
||
|
public:
|
||
|
#ifndef BOOST_NO_CXX11_HDR_FUNCTIONAL
|
||
|
typedef IntegerType first_argument_type;
|
||
|
typedef IntegerType second_argument_type;
|
||
|
typedef IntegerType result_type;
|
||
|
#endif
|
||
|
IntegerType operator()(IntegerType const &a, IntegerType const &b)const
|
||
|
{
|
||
|
return boost::integer::lcm(a, b);
|
||
|
}
|
||
|
};
|
||
|
|
||
|
} // namespace integer
|
||
|
} // namespace boost
|
||
|
|
||
|
#ifdef BOOST_MSVC
|
||
|
#pragma warning(pop)
|
||
|
#endif
|
||
|
|
||
|
#endif // BOOST_INTEGER_COMMON_FACTOR_RT_HPP
|