verdnatura-chat/ios/Pods/boost-for-react-native/boost/multiprecision/miller_rabin.hpp

227 lines
6.3 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 http://www.boost.org/LICENSE_1_
#ifndef BOOST_MP_MR_HPP
#define BOOST_MP_MR_HPP
#include <boost/random.hpp>
#include <boost/multiprecision/integer.hpp>
namespace boost{
namespace multiprecision{
namespace detail{
template <class I>
bool check_small_factors(const I& n)
{
static const boost::uint32_t small_factors1[] = {
3u, 5u, 7u, 11u, 13u, 17u, 19u, 23u };
static const boost::uint32_t pp1 = 223092870u;
boost::uint32_t m1 = integer_modulus(n, pp1);
for(unsigned i = 0; i < sizeof(small_factors1) / sizeof(small_factors1[0]); ++i)
{
BOOST_ASSERT(pp1 % small_factors1[i] == 0);
if(m1 % small_factors1[i] == 0)
return false;
}
static const boost::uint32_t small_factors2[] = {
29u, 31u, 37u, 41u, 43u, 47u };
static const boost::uint32_t pp2 = 2756205443u;
m1 = integer_modulus(n, pp2);
for(unsigned i = 0; i < sizeof(small_factors2) / sizeof(small_factors2[0]); ++i)
{
BOOST_ASSERT(pp2 % small_factors2[i] == 0);
if(m1 % small_factors2[i] == 0)
return false;
}
static const boost::uint32_t small_factors3[] = {
53u, 59u, 61u, 67u, 71u };
static const boost::uint32_t pp3 = 907383479u;
m1 = integer_modulus(n, pp3);
for(unsigned i = 0; i < sizeof(small_factors3) / sizeof(small_factors3[0]); ++i)
{
BOOST_ASSERT(pp3 % small_factors3[i] == 0);
if(m1 % small_factors3[i] == 0)
return false;
}
static const boost::uint32_t small_factors4[] = {
73u, 79u, 83u, 89u, 97u };
static const boost::uint32_t pp4 = 4132280413u;
m1 = integer_modulus(n, pp4);
for(unsigned i = 0; i < sizeof(small_factors4) / sizeof(small_factors4[0]); ++i)
{
BOOST_ASSERT(pp4 % small_factors4[i] == 0);
if(m1 % small_factors4[i] == 0)
return false;
}
static const boost::uint32_t small_factors5[6][4] = {
{ 101u, 103u, 107u, 109u },
{ 113u, 127u, 131u, 137u },
{ 139u, 149u, 151u, 157u },
{ 163u, 167u, 173u, 179u },
{ 181u, 191u, 193u, 197u },
{ 199u, 211u, 223u, 227u }
};
static const boost::uint32_t pp5[6] =
{
121330189u,
113u * 127u * 131u * 137u,
139u * 149u * 151u * 157u,
163u * 167u * 173u * 179u,
181u * 191u * 193u * 197u,
199u * 211u * 223u * 227u
};
for(unsigned k = 0; k < sizeof(pp5) / sizeof(*pp5); ++k)
{
m1 = integer_modulus(n, pp5[k]);
for(unsigned i = 0; i < 4; ++i)
{
BOOST_ASSERT(pp5[k] % small_factors5[k][i] == 0);
if(m1 % small_factors5[k][i] == 0)
return false;
}
}
return true;
}
inline bool is_small_prime(unsigned n)
{
static const unsigned char p[] =
{
3u, 5u, 7u, 11u, 13u, 17u, 19u, 23u, 29u, 31u,
37u, 41u, 43u, 47u, 53u, 59u, 61u, 67u, 71u, 73u,
79u, 83u, 89u, 97u, 101u, 103u, 107u, 109u, 113u,
127u, 131u, 137u, 139u, 149u, 151u, 157u, 163u,
167u, 173u, 179u, 181u, 191u, 193u, 197u, 199u,
211u, 223u, 227u
};
for(unsigned i = 0; i < sizeof(p) / sizeof(*p); ++i)
{
if(n == p[i])
return true;
}
return false;
}
template <class I>
typename enable_if_c<is_convertible<I, unsigned>::value, unsigned>::type
cast_to_unsigned(const I& val)
{
return static_cast<unsigned>(val);
}
template <class I>
typename disable_if_c<is_convertible<I, unsigned>::value, unsigned>::type
cast_to_unsigned(const I& val)
{
return val.template convert_to<unsigned>();
}
} // namespace detail
template <class I, class Engine>
typename enable_if_c<number_category<I>::value == number_kind_integer, bool>::type
miller_rabin_test(const I& n, unsigned trials, Engine& gen)
{
#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable:4127)
#endif
typedef I number_type;
if (n == 2)
return true; // Trivial special case.
if(bit_test(n, 0) == 0)
return false; // n is even
if(n <= 227)
return detail::is_small_prime(detail::cast_to_unsigned(n));
if(!detail::check_small_factors(n))
return false;
number_type nm1 = n - 1;
//
// Begin with a single Fermat test - it excludes a lot of candidates:
//
number_type q(228), x, y; // We know n is greater than this, as we've excluded small factors
x = powm(q, nm1, n);
if(x != 1u)
return false;
q = n - 1;
unsigned k = lsb(q);
q >>= k;
// Declare our random number generator:
boost::random::uniform_int_distribution<number_type> dist(2, n - 2);
//
// Execute the trials:
//
for(unsigned i = 0; i < trials; ++i)
{
x = dist(gen);
y = powm(x, q, n);
unsigned j = 0;
while(true)
{
if(y == nm1)
break;
if(y == 1)
{
if(j == 0)
break;
return false; // test failed
}
if(++j == k)
return false; // failed
y = powm(y, 2, n);
}
}
return true; // Yeheh! probably prime.
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
}
template <class I>
typename enable_if_c<number_category<I>::value == number_kind_integer, bool>::type
miller_rabin_test(const I& x, unsigned trials)
{
static mt19937 gen;
return miller_rabin_test(x, trials, gen);
}
template <class tag, class Arg1, class Arg2, class Arg3, class Arg4, class Engine>
bool miller_rabin_test(const detail::expression<tag, Arg1, Arg2, Arg3, Arg4> & n, unsigned trials, Engine& gen)
{
typedef typename detail::expression<tag, Arg1, Arg2, Arg3, Arg4>::result_type number_type;
return miller_rabin_test(number_type(n), trials, gen);
}
template <class tag, class Arg1, class Arg2, class Arg3, class Arg4>
bool miller_rabin_test(const detail::expression<tag, Arg1, Arg2, Arg3, Arg4> & n, unsigned trials)
{
typedef typename detail::expression<tag, Arg1, Arg2, Arg3, Arg4>::result_type number_type;
return miller_rabin_test(number_type(n), trials);
}
}} // namespaces
#endif