import sys
input = sys.stdin.readline

C=input().split()

x=C.index("?")

ANS=""

C[x]="1"

if len(set(C))==3 and (max(C)==C[1] or min(C)==C[1]):
    ANS+="1"
C[x]="4"

if len(set(C))==3 and (max(C)==C[1] or min(C)==C[1]):
    ANS+="4"

print(ANS)