It prompts the user to enter an integer N. It prints out if it is a prime or not. If not, it prints out all of its proper factors.


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*     MYCPLUS Sample Code - http://www.mycplus.com     *
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#include 


int main(void) {
  int n,
    lcv,
    flag; /* flag initially is 1 and becomes 0 if we determine that n
      is not a prime */

  printf("Enter value of N > ");
  scanf("%d", &n);
  for (lcv=2, flag=1; lcv <= (n / 2); lcv++) {
    if ((n % lcv) == 0) {
      if (flag)
 printf("The non-trivial factors of %d are: \n", n);
      flag = 0;
      printf("\t%d\n", lcv);
    }
  }
  if (flag)
    printf("%d is prime\n", n);
}