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 Scala (2.13.1) (judge verdict: Accepted)

object Main {
  import scala.io.StdIn.readLine
  def main(args: Array[String]): Unit = {
    val k = readLine.trim().toInt
    val ab = readLine.split(" ").map(_.toInt)
    val a = ab(0)
    val b = ab(1)

    if((k - (a % k)) % k <= b - a) {
      println("OK")
    } else {
      println("NG")
    }
  }
}