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>
#include<stdlib.h>
#include<string.h>
#include <assert.h>

int main(void){
		int a,b,c,d;
    //int ans;
		scanf("%d",&a);
    scanf("%d",&b);
    scanf("%d",&c);

    d = c/a;
    //printf("%d\n",d);
    d = d*a;
    //printf("%d\n",d);

    //ans = c-d;

    //printf("%d\n",ans);

    if(b <= d && d <= c){
      puts("OK");
    }
    else{
      puts("NG");
    }


		return 0;
}