1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
/*=============================================================================
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;
}
|
