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`.

Examples

Input

7
500 600


Output

OK


Input

4
5 7


Output

NG


Input

1
11 11


Output

OK
k=int(input())

a,b=input().split()
a=int(a)
b=int(b)
x=b//k
if x*k>=a:
    print("OK")
else:
    print("NG")