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 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;
public class Main{
  public static void main (String args[]){
    Scanner sc = new Scanner(System.in);
    int x = sc.nextInt();
    int a = sc.nextInt();
    int b = sc.nextInt();
    System.out.print(Logic.run(x,a,b));
  }
}
class Logic{
  public static String run(int x,int a,int b){
    String resMes="";
    for ( int i = a; i<=b;i++){
      if ( i%x == 0 ){
        resMes="OK";
        break;
      }
    }
    if (resMes.equals("")){
      resMes = "NG";
    }
    return resMes;
  }
}