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
FAST_IO = 0
if FAST_IO:
    import io, sys, atexit
    rr = iter(sys.stdin.read().splitlines()).next
    sys.stdout = _OUTPUT_BUFFER = io.BytesIO()
    @atexit.register
    def write():
        sys.__stdout__.write(_OUTPUT_BUFFER.getvalue())
else:
    rr = raw_input
rri = lambda: int(rr())
rrm = lambda: map(int, rr().split())

####

def solve(K, A, B):
    q,r = divmod(A, K)
    q += r> 0
    q *= K
    return A <= q <= B

K = rri()
A, B = rrm()
ans = solve(K, A, B)
print "OK" if ans else "NG"
