#include <stdio.h>
int book(int n, int d, int e) {
  if(d * e > n) {
    printf("OK\n");
  }else {
    printf("NG\n");
  }
}

int main(void) {
  int n,d,e;
  printf("n = ");
  scanf("%d", &n);
  printf("d = ");
  scanf("%d", &d);
  printf("e = ");
  scanf("%d", &e);

  book(n,d,e);

  return 0;
}