test/gourdinl/c/prime.c


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/* prime1.c  It prompts the user to enter an integer N. It prints out
 *           if it is a prime or not. If not, it prints out a factor of N.
 */

#include <stdio.h>

int main(int n) {
  int i;
  int flag;

  flag = 1;
  for (i=2; (i<(n/2)) && flag; ) { /* May be we do not need to test
			values of i greater than the square root of n? */
    if ((n % i) == 0) /* If true n is divisible by i */
      flag = 0;
    else
      i++;
  }
 
  if (flag)
    return 1;
  return 0;
}