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