def larger(x, y):
	if x > y: return x
	else: return y
def smaller(x, y):
	if x < y: return x
	else: return y

A = raw_input().split()
hatena = 0
for i in range(0, 3):
	if A[i] == '?': hatena = i
kadomatsu1 = [A[0], A[1], A[2]]
kadomatsu4 = [A[0], A[1], A[2]]
kadomatsu1[hatena] = '1'
kadomatsu4[hatena] = '4'
ans = ''
if larger(larger(kadomatsu1[0], kadomatsu1[2]), kadomatsu1[1]) == kadomatsu1[1] or smaller(smaller(kadomatsu1[0], kadomatsu1[2]), kadomatsu1[1]) == kadomatsu1[1]:
	ans = ans + '1'
if larger(larger(kadomatsu4[0], kadomatsu4[2]), kadomatsu4[1]) == kadomatsu4[1] or smaller(smaller(kadomatsu4[0], kadomatsu4[2]), kadomatsu4[1]) == kadomatsu4[1]:
	ans = ans + '4'
print ans