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

c = abs(a)
d = abs(b)

c = list(str(c))
d = list(str(d))

e = sorted(list(set(c)))
f = sorted(list(set(d)))

if a != 10 and b != 10 and c.count('1') == 1 and d.count('1') == 1 and 1 <= int(e[-1]) <= 9 and 1 <= int(f[-1]) <= 9 and len(e) == len(f) == 2:
    g = a * b
    print(g//10)
else:
    h = a * b
    if -99999999 <= h <= 99999999:
        print(h)
    else:
        print('E')