prime.c revision 24139
1219820Sjeff/*
2219820Sjeff * Prime number generator.  It prints on stdout the next prime number
3219820Sjeff * higher than the number specified as argv[1].
4219820Sjeff */
5219820Sjeff
6219820Sjeff#include <math.h>
7219820Sjeff
8219820Sjeffmain(argc, argv)
9219820Sjeff
10219820Sjeffint argc;
11219820Sjeffchar *argv[];
12219820Sjeff
13219820Sjeff{
14219820Sjeff    double i, j;
15219820Sjeff    int f;
16219820Sjeff
17219820Sjeff    if (argc < 2)
18219820Sjeff    {
19219820Sjeff	exit(1);
20219820Sjeff    }
21219820Sjeff
22219820Sjeff    i = atoi(argv[1]);
23219820Sjeff    while (i++)
24219820Sjeff    {
25219820Sjeff	f=1;
26219820Sjeff	for (j=2; j<i; j++)
27219820Sjeff	{
28219820Sjeff	    if ((i/j)==floor(i/j))
29219820Sjeff	    {
30219820Sjeff		f=0;
31219820Sjeff		break;
32219820Sjeff	    }
33219820Sjeff	}
34	if (f)
35	{
36	    printf("%.0f\n", i);
37	    exit(0);
38	}
39    }
40}
41