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;

public class WeLoveGolf{
    public static void Main(){
        
        var K = int.Parse(Console.ReadLine());
        var input = Console.ReadLine().Split(' ');
        var A = int.Parse(input[0]);
        var B = int.Parse(input[1]);
        var result = "";
        
        for(int i = A; i * A < B; i++)
        {
            if(i % A == 0)
            {
                result = "OK";
                break;
            }
        }
        
        if(result == "")
        {
            Console.WriteLine("NG");
        }
        else
        {
            Console.WriteLine(result);
        }
    }
}