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 Python (3.8.2) (judge verdict: Wrong Answer)

K = int(input())
A,B = map(int, input().split())
ans = 1

if  0 < abs(A-B) < K:
    for i in range(A, B):
        ans = i % K
        if ans == 0:
            print('OK')
            break    
    if ans != 0:
        print('NG')
elif abs(A -B) == 0:
    if A % K == 0 :
        print('OK')
    else:
        print('NG')
elif abs(A-B) >= K :
    print('OK')