indivisible-legacy/src/main.c
Nicolás A. Ortega Froysa 874cc75431
Only test up to the sqrt.
2018-10-19 09:05:46 +02:00

91 lines
2.0 KiB
C

/*
* Copyright (C) 2018 Ortega Froysa, Nicolás <nortega@themusicinnoise.net>
* Author: Ortega Froysa, Nicolás <nortega@themusicinnoise.net>
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <argp.h>
#include <gmp.h>
#include "global.h"
#include "linked_list.h"
int main(int argc, char *argv[]) {
struct args args = { 1000, 0 };
argp_parse(&argp, argc, argv, 0, 0, &args);
if(args.count == 0)
{
fprintf(stderr, "ERROR: count must be larger than 0.\n");
return 1;
}
struct llist prime_list;
llist_init(&prime_list);
{
// initialize the list with 2
mpz_t tmp;
mpz_init(tmp);
mpz_set_ui(tmp, 2);
llist_add(&prime_list, tmp);
mpz_clear(tmp);
if(args.verbose)
puts("2");
}
mpz_t aux;
mpz_init(aux);
mpz_set_ui(aux, 3);
while(prime_list.size < args.count)
{
struct llist_item *item = prime_list.first;
int is_prime = 1;
mpz_t root;
mpz_init(root);
mpz_sqrt(root, aux);
while(item && mpz_cmp(item->num, root) < 0)
{
if(mpz_divisible_p(aux, item->num))
{
is_prime = 0;
break;
}
item = item->next;
}
if(is_prime)
{
llist_add(&prime_list, aux);
if(args.verbose)
{
mpz_out_str(stdout, 10, aux);
printf("\n");
}
}
mpz_add_ui(aux, aux, 2);
}
printf("The %zu prime is ", prime_list.size);
mpz_out_str(stdout, 10, prime_list.last->num);
printf("\n");
llist_deinit(&prime_list);
return 0;
}