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 judge(int a,int b,int k)
{
	for (int i = a;i <= b;i++){
			if (i % k == 0)return 1;
		}

	return 2;
}

int main()
{
	int A,B,K;

	scanf("%d",&K);
	scanf("%d %d",&A,&B);

	if (judge(A,B,K) == 1){
		printf("OK\n");
	}else{
		printf("NG\n");
	}

	return 0;
}