import itertools

import math

import numpy as np

import fractions

from collections import deque

from itertools import combinations

from functools import reduce

from functools import lru_cache

import bisect

import sys

sys.setrecursionlimit(10**9)



def main():

    K = int(eval(input()))

    A,B = list(map(int,input().split()))



    ok = False

    for k in range(A,B+1):

        if k % K == 0:

            ok = True





    print(("OK" if ok else "NG"))











if __name__ == "__main__":

  main()

import sys

sys.setrecursionlimit(10**9)



def mi(): return list(map(int,input().split()))

def ii(): return int(eval(input()))

def isp(): return input().split()

def deb(text): print(("-------\n{}\n-------".format(text)))



INF=10**20

def main():

    K=ii()

    A,B=mi()



    for x in range(A,B+1):

        if x % K == 0:

            print("OK")

            exit()



    print("NG")











if __name__ == "__main__":

    main()
import itertools
import math
import numpy as np
import fractions
from collections import deque
from itertools import combinations
from functools import reduce
from functools import lru_cache
import bisect
import sys

sys.setrecursionlimit(10**9)


def main():
    K = int(eval(input()))
    A, B = list(map(int, input().split()))
    ok = False
    for k in range(A, B + 1):
        if k % K == 0:
            ok = True
    print(("OK" if ok else "NG"))


if __name__ == "__main__":
    main()

import sys

sys.setrecursionlimit(10**9)


def mi():
    return list(map(int, input().split()))


def ii():
    return int(eval(input()))


def isp():
    return input().split()


def deb(text):
    print(("-------\n{}\n-------".format(text)))


INF = 10**20


def main():
    K = ii()
    A, B = mi()
    for x in range(A, B + 1):
        if x % K == 0:
            print("OK")
            exit()
    print("NG")


if __name__ == "__main__":
    main()

-import itertools -import math -import numpy as np -import fractions -from collections import deque -from itertools import combinations -from functools import reduce -from functools import lru_cache -import bisect +def mi(): +    return list(map(int, input().split())) + + +def ii(): +    return int(eval(input())) + + +def isp(): +    return input().split() + + +def deb(text): + + +INF = 10**20 + + -    K = int(eval(input())) -    A, B = list(map(int, input().split())) -    ok = False -    for k in range(A, B + 1): -        if k % K == 0: -            ok = True -    print(("OK" if ok else "NG")) +    K = ii() +    A, B = mi() +    for x in range(A, B + 1): +        if x % K == 0: +            print("OK") +            exit() +    print("NG")