Problem:
Score: 100 points

Problem Statement

Takahashi the Jumbo will practice golf.

His objective is to get a carry distance that is a multiple of K, while he can only make a carry distance of between A and B (inclusive).

If he can achieve the objective, print OK; if he cannot, print NG.

Constraints

All values in input are integers.

1 \leq A \leq B \leq 1000

1 \leq K \leq 1000

Input

Input is given from Standard Input in the following format:

K
A B

Output

If he can achieve the objective, print OK; if he cannot, print NG.

Sample Input 1

7
500 600

Sample Output 1

OK

Among the multiples of 7, for example, 567 lies between 500 and 600.

Sample Input 2

4
5 7

Sample Output 2

NG

No multiple of 4 lies between 5 and 7.

Sample Input 3

1
11 11

Sample Output 3

OK

Solution in C (Clang 10.0.0) (judge verdict: Accepted)

#include <stdio.h>
int main(void)
{

  int k;
  int a;
  int b;
  int x;
  int c= 0;

  scanf("%d%d%d", &k, &a, &b);

  for (x = a; x <= b; x++){
    if (x % k == 0) c+= 1;
  }

  if (c>=1) printf("OK");
  else printf("NG");

  return 0;

}