74 lines
2.2 KiB
C++
74 lines
2.2 KiB
C++
/*=============================================================================
|
|
|
|
This file is part of FLINT.
|
|
|
|
FLINT 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 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
FLINT 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.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with FLINT; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
=============================================================================*/
|
|
/******************************************************************************
|
|
|
|
Copyright (C) 2011 Fredrik Johansson
|
|
Copyright (C) 2013 Tom Bachmann (C++ adaptation)
|
|
|
|
******************************************************************************/
|
|
|
|
/*
|
|
Demo FLINT program for balanced multimodular reduction and
|
|
reconstruction using the Chinese Remainder Theorem.
|
|
*/
|
|
|
|
#include <iostream>
|
|
#include <vector>
|
|
#include "fmpzxx.h"
|
|
#include "ulong_extras.h"
|
|
|
|
using namespace flint;
|
|
|
|
int main(int argc, char* argv[])
|
|
{
|
|
if (argc != 3)
|
|
{
|
|
std::cerr << "Syntax: crt <integer> <num_primes>\n";
|
|
return 1;
|
|
}
|
|
|
|
slong num_primes = atoi(argv[2]);
|
|
|
|
if (num_primes < 1)
|
|
{
|
|
std::cerr << "Requires num_primes >= 1\n";
|
|
return 2;
|
|
}
|
|
|
|
fmpzxx x(argv[1]);
|
|
|
|
std::vector<mp_limb_t> primes(num_primes), residues(num_primes);
|
|
primes[0] = 2;
|
|
for (unsigned i = 1; i < num_primes; i++)
|
|
primes[i] = n_nextprime(primes[i-1], 0);
|
|
|
|
fmpz_combxx comb(primes);
|
|
multi_mod(residues, x, comb);
|
|
|
|
for (unsigned i = 0; i < num_primes; i++)
|
|
std::cout << "residue mod " << primes[i]
|
|
<< " = " << residues[i] << '\n';
|
|
|
|
std::cout << "reconstruction = " << multi_CRT(residues, comb, true)
|
|
<< '\n';
|
|
|
|
return 0;
|
|
}
|