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



if W >= S:

    print('unsafe')

else:

    print('safe')
S, W = input().split()

if int(W) >= int(S):

  print('unsafe')

else:

  print('safe')

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

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

-S, W = list(map(int, input().split())) -if W >= S: +S, W = input().split() +if int(W) >= int(S):