vvod = input()
chisla = []
res = ""

for i in vvod:
    if i.isdigit():
        chisla.append(i)

for i in range(1, 10):
    if str(i) not in chisla:
        res = res + str(i)

if len(res) == 0:
    res = "0"

print(int(res))