a, b = [int(a) for a in input().split()]

print(("unsafe" if a <= b else "safe"))
a, b=[int(yy) for yy in input().split()]

if b>=a:

	print('unsafe')

else:

	print("safe")

a, b = [int(a) for a in input().split()]
print(("unsafe" if a <= b else "safe"))

a, b = [int(yy) for yy in input().split()]
if b >= a:
    print("unsafe")
else:
    print("safe")

-a, b = [int(a) for a in input().split()] -print(("unsafe" if a <= b else "safe")) +a, b = [int(yy) for yy in input().split()] +if b >= a: +    print("unsafe") +else: +    print("safe")