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 JavaScript (Node.js 12.16.1) (judge verdict: Accepted)

const Main = input => {
    const inp = input.split("\n");//["K", "A B"]
    const ab = inp[1].split(" ");//["A", "B"]
    const k = parseInt(inp[0], 10);
    const a = parseInt(ab[0], 10);
    const b = parseInt(ab[1], 10);

    let result = "NG";
    const min = Math.ceil(a / k);
    if(a <= k*min && k*min <= b) result = "OK";
    console.log(result);
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));