ext-boost/boost/multiprecision/detail/digits.hpp
2024-09-02 12:14:13 +02:00

50 lines
1.3 KiB
C++

///////////////////////////////////////////////////////////////
// Copyright 2012 John Maddock. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
#ifndef BOOST_MP_DETAIL_DIGITS_HPP
#define BOOST_MP_DETAIL_DIGITS_HPP
namespace boost { namespace multiprecision { namespace detail {
inline constexpr unsigned long digits10_2_2(unsigned long d10)
{
return (d10 * 1000uL) / 301uL + ((d10 * 1000uL) % 301 ? 2u : 1u);
}
inline constexpr unsigned long digits2_2_10(unsigned long d2)
{
return (d2 * 301uL) / 1000uL;
}
#if ULONG_MAX != SIZE_MAX
inline constexpr std::size_t digits10_2_2(std::size_t d10)
{
return (d10 * 1000uL) / 301uL + ((d10 * 1000uL) % 301 ? 2u : 1u);
}
inline constexpr std::size_t digits2_2_10(std::size_t d2)
{
return (d2 * 301uL) / 1000uL;
}
template <class I>
inline constexpr typename std::enable_if<sizeof(I) <= sizeof(unsigned long), unsigned long>::type digits10_2_2(I d10)
{
return digits10_2_2(static_cast<unsigned long>(d10));
}
template <class I>
inline constexpr typename std::enable_if<sizeof(I) <= sizeof(unsigned long), unsigned long>::type digits2_2_10(I d10)
{
return digits2_2_10(static_cast<unsigned long>(d10));
}
#endif
}}} // namespace boost::multiprecision::detail
#endif