a,b= list(map(int,input().split()))

print((max((a+b,a-b,a*b))))

a,b= list(map(int,input().split()))

print((max(a+b,a-b,a*b)))

a, b = list(map(int, input().split()))
print((max((a + b, a - b, a * b))))

a, b = list(map(int, input().split()))
print((max(a + b, a - b, a * b)))

-print((max((a + b, a - b, a * b)))) +print((max(a + b, a - b, a * b)))