#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define MAXIMUM 19

int IsPrime(int i) {
  int divider;
  int sqr = sqrt(i);
  while (sqr * sqr < i) {
    sqr++;
  }
  for (divider = 2; divider < sqr; ++divider) {
    printf("Checking %d against %d\n", i, divider);
    if (i % divider == 0) {
      return 0;
    }
  }
  return 1;
}

int main() {
  int i;
  for (i = 2; i <= MAXIMUM; ++i) {
    printf("%d's primeness is %d\n", i, IsPrime(i));
  }
  return EXIT_SUCCESS;
}