100 atcoder#ABC165A. [ABC165A] We Love Golf

[ABC165A] We Love Golf

Score: 100100 points

Problem Statement

Takahashi the Jumbo will practice golf.

His objective is to get a carry distance that is a multiple of KK, while he can only make a carry distance of between AA and BB (inclusive).

If he can achieve the objective, print OK; if he cannot, print NG.

Constraints

  • All values in input are integers.
  • 1AB10001 \leq A \leq B \leq 1000
  • 1K10001 \leq K \leq 1000

Input

Input is given from Standard Input in the following format:

KK

AA BB

Output

If he can achieve the objective, print OK; if he cannot, print NG.

7
500 600
OK

Among the multiples of 77, for example, 567567 lies between 500500 and 600600.

4
5 7
NG

No multiple of 44 lies between 55 and 77.

1
11 11
OK