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Diffstat (limited to 'boost/integer/common_factor_ct.hpp')
-rw-r--r-- | boost/integer/common_factor_ct.hpp | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/boost/integer/common_factor_ct.hpp b/boost/integer/common_factor_ct.hpp new file mode 100644 index 000000000..0671d161c --- /dev/null +++ b/boost/integer/common_factor_ct.hpp @@ -0,0 +1,102 @@ +// Boost common_factor_ct.hpp header file ----------------------------------// + +// (C) Copyright Daryle Walker and Stephen Cleary 2001-2002. +// Distributed under the Boost Software License, Version 1.0. (See +// accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +// See http://www.boost.org for updates, documentation, and revision history. + +#ifndef BOOST_INTEGER_COMMON_FACTOR_CT_HPP +#define BOOST_INTEGER_COMMON_FACTOR_CT_HPP + +#include <boost/integer_fwd.hpp> // self include +#include <boost/config.hpp> // for BOOST_STATIC_CONSTANT, etc. + +namespace boost +{ +namespace integer +{ + +// Implementation details --------------------------------------------------// + +namespace detail +{ + // Build GCD with Euclid's recursive algorithm + template < static_gcd_type Value1, static_gcd_type Value2 > + struct static_gcd_helper_t + { + private: + BOOST_STATIC_CONSTANT( static_gcd_type, new_value1 = Value2 ); + BOOST_STATIC_CONSTANT( static_gcd_type, new_value2 = Value1 % Value2 ); + + #ifndef __BORLANDC__ + #define BOOST_DETAIL_GCD_HELPER_VAL(Value) static_cast<static_gcd_type>(Value) + #else + typedef static_gcd_helper_t self_type; + #define BOOST_DETAIL_GCD_HELPER_VAL(Value) (self_type:: Value ) + #endif + + typedef static_gcd_helper_t< BOOST_DETAIL_GCD_HELPER_VAL(new_value1), + BOOST_DETAIL_GCD_HELPER_VAL(new_value2) > next_step_type; + + #undef BOOST_DETAIL_GCD_HELPER_VAL + + public: + BOOST_STATIC_CONSTANT( static_gcd_type, value = next_step_type::value ); + }; + + // Non-recursive case + template < static_gcd_type Value1 > + struct static_gcd_helper_t< Value1, 0UL > + { + BOOST_STATIC_CONSTANT( static_gcd_type, value = Value1 ); + }; + + // Build the LCM from the GCD + template < static_gcd_type Value1, static_gcd_type Value2 > + struct static_lcm_helper_t + { + typedef static_gcd_helper_t<Value1, Value2> gcd_type; + + BOOST_STATIC_CONSTANT( static_gcd_type, value = Value1 / gcd_type::value + * Value2 ); + }; + + // Special case for zero-GCD values + template < > + struct static_lcm_helper_t< 0UL, 0UL > + { + BOOST_STATIC_CONSTANT( static_gcd_type, value = 0UL ); + }; + +} // namespace detail + + +// Compile-time greatest common divisor evaluator class declaration --------// + +template < static_gcd_type Value1, static_gcd_type Value2 > struct static_gcd +{ + BOOST_STATIC_CONSTANT( static_gcd_type, value = (detail::static_gcd_helper_t<Value1, Value2>::value) ); +}; // boost::integer::static_gcd + +#if !defined(BOOST_NO_INCLASS_MEMBER_INITIALIZATION) +template< static_gcd_type Value1, static_gcd_type Value2 > static_gcd_type const static_gcd< Value1, Value2 >::value; +#endif + +// Compile-time least common multiple evaluator class declaration ----------// + +template < static_gcd_type Value1, static_gcd_type Value2 > struct static_lcm +{ + BOOST_STATIC_CONSTANT( static_gcd_type, value = (detail::static_lcm_helper_t<Value1, Value2>::value) ); +}; // boost::integer::static_lcm + +#if !defined(BOOST_NO_INCLASS_MEMBER_INITIALIZATION) +template< static_gcd_type Value1, static_gcd_type Value2 > static_gcd_type const static_lcm< Value1, Value2 >::value; +#endif + +} // namespace integer +} // namespace boost + + +#endif // BOOST_INTEGER_COMMON_FACTOR_CT_HPP |