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

if a == b == c:
    print(a)
elif a == b:
    print(c)
elif a == c:
    print(b)
elif b == c:
    print(a)
else:
    s = {0, 1, 2, 3}
    t = {a, b, c}
    st = s - t
    print(*st)