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 (GCC 9.2.1) (judge verdict: Accepted)

#include<stdio.h>
int main(void)
{
    int K,A,B;
    int i;
  
    scanf("%d",&K);
    scanf("%d%d",&A,&B);
  
    if((A==B)&&(A%K==0)) { printf("OK\n"); return 0; }
    else{ 
      for(i=0;i<=B-A;i++){
        if((A+i)%K==0){
          printf("OK\n");
          return 0;
        }
      }
    }
  
    printf("NG\n");
      
    return 0;
}