A=input()
B=input()
ans=0
if A=="0":
    ans+=1
elif A.isdigit():
    if int(A)<=12345:
        ans+=1

if B=="0":
    ans+=1
elif B.isdigit():
    if int(B)<=12345:
        ans+=1
if ans==2:
    print("OK")
else:
    print("NG")