l = list(map(str, input().split()))
n = l.index("?")
ans = ""

l[n] = "1"
if l[1] == max(l) or l[1] == min(l):
    ans += "1"

l[n] = "4"
if l[1] == max(l) or l[1] == min(l):
    ans += "4"

print(ans)