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: Accepted)

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

namespace atcorder
{
    class Program
    {
        static void Main(string[] args)
        {
            int K = int.Parse(Console.ReadLine());
            int[] intArray = Console.ReadLine().Split(' ').Select(i => int.Parse(i)).ToArray();
            int A = intArray[0];
            int B = intArray[1];
            for(int i = A; i <= B; i++)
            {
                if(i % K == 0)
                {
                    Console.WriteLine("OK");
                    return;
                }
            }
            Console.WriteLine("NG");
        }
    }
}

//文字配列の取得
//string[] strArray = Console.ReadLine().Split(' ').ToArray();
//string S = strArray[0];
//string T = strArray[1];

//文字列の取得
//string s = Console.ReadLine();

//数字配列の取得
//int[] intArray = Console.ReadLine().Split(' ').Select(i => int.Parse(i)).ToArray();
//int H = intArray[0];
//int W = intArray[1];

//数字の取得
//int N = int.Parse(Console.ReadLine());

//リスト型(int)の取得
//List<int> A = new List<int>(Console.ReadLine().Split(' ').Select(i => int.Parse(i)).ToArray());

//出力
//Console.WriteLine(ans);
//Console.WriteLine("Yes");
//Console.WriteLine("No");
//Console.WriteLine(cnt);