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 Rust (1.42.0) (judge verdict: Accepted)

// -*- coding:utf-8-unix -*-

use proconio::input;

// ABC086C - Traveling
// https://atcoder.jp/contests/abs/fasks/arc089_a
fn main() {
    input! {
        k: usize,
        a: usize,
        b: usize,
    }
    let mut ans = false;
    if a % k == 0 || b % k == 0 {
        ans = true;
    } else if b - a >= k {
        ans = true;
    } else if a % k > b % k {
        ans = true;
    }

    if ans == true {
        println!("OK");
    } else {
        println!("NG");
    }
}