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/* Classify numbers as probable primes, primes or composites.
With -q return true if the following argument is a (probable) prime.
Copyright 1999, 2000, 2002, 2005, 2012 Free Software Foundation, Inc.
This program 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 3 of the License, or (at your option) any later
version.
This program 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
this program. If not, see https://www.gnu.org/licenses/. */
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "gmp.h"
char *progname;
void
print_usage_and_exit ()
{
fprintf (stderr, "usage: %s -q nnn\n", progname);
fprintf (stderr, "usage: %s nnn ...\n", progname);
exit (-1);
}
int
main (int argc, char **argv)
{
mpz_t n;
int i;
progname = argv[0];
if (argc < 2)
print_usage_and_exit ();
mpz_init (n);
if (argc == 3 && strcmp (argv[1], "-q") == 0)
{
if (mpz_set_str (n, argv[2], 0) != 0)
print_usage_and_exit ();
exit (mpz_probab_prime_p (n, 25) == 0);
}
for (i = 1; i < argc; i++)
{
int class;
if (mpz_set_str (n, argv[i], 0) != 0)
print_usage_and_exit ();
class = mpz_probab_prime_p (n, 25);
mpz_out_str (stdout, 10, n);
if (class == 0)
puts (" is composite");
else if (class == 1)
puts (" is a probable prime");
else /* class == 2 */
puts (" is a prime");
}
exit (0);
}
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