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# (.NET Core 3.1.201) (judge verdict: Wrong Answer)

    using System;
    using System.Collections.Generic;
    using System.Linq;


    class Program {
        static void Main (string[] args) {
            int n = int.Parse(Console.ReadLine());
            string[]　m = Console.ReadLine().Split(" ");
            int a = int.Parse(m[0]);
            int b = int.Parse(m[1]);
            string ans = string.Empty;

            if((a/n) != (b/n)){
                ans = "OK";
            }else if(a == b && a%b == 0){
                ans = "OK";
            }else{
                ans = "NG";
            }
            if(b<a) ans = "NG";

            Console.WriteLine(ans);

        }
    }