prime.c revision 89750
1219820Sjeff/* 2219820Sjeff * Prime number generator. It prints on stdout the next prime number 3 * higher than the number specified as argv[1]. 4 */ 5 6#include <stdio.h> 7#include <math.h> 8 9main(argc, argv) 10 11int argc; 12char *argv[]; 13 14{ 15 double i, j; 16 int f; 17 18 if (argc < 2) 19 { 20 exit(1); 21 } 22 23 i = atoi(argv[1]); 24 while (i++) 25 { 26 f=1; 27 for (j=2; j<i; j++) 28 { 29 if ((i/j)==floor(i/j)) 30 { 31 f=0; 32 break; 33 } 34 } 35 if (f) 36 { 37 printf("%.0f\n", i); 38 exit(0); 39 } 40 } 41} 42