S,W= list(map(int, input().split()))

if S<=W:

  print("unsafe")

elif S>W:

  print("safe")
s,w =input().split()

if int(w) >= int(s):

  print("unsafe")

else:

  print("safe")

  
S, W = list(map(int, input().split()))
if S <= W:
    print("unsafe")
elif S > W:
    print("safe")

s, w = input().split()
if int(w) >= int(s):
    print("unsafe")
else:
    print("safe")

-S, W = list(map(int, input().split())) -if S <= W: +s, w = input().split() +if int(w) >= int(s): -elif S > W: +else: