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 Java (OpenJDK 11.0.6) (judge verdict: Wrong Answer)

import java.util.Scanner;

public class Main {
	static int K;
	static int A;
	static int B;
	static int a;
	static int b;
	public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		K=sc.nextInt();
		A=sc.nextInt();
		B=sc.nextInt();
		a=A/K;
		b=B/K;
		if(a!=b||A==B&&A%K==0) {
			System.out.println("OK");
		}
		else {
			System.out.println("NG");
		}
	}
}