user = input()
a, b = list(map(int, user[0::2])), list(map(int, user[1::2]))
print(abs(sum(a) - sum(b)))

eb194f1ab8a3ef769577956258945c65d73eb190
<mask token>

<mask token>
print(abs(sum(a) - sum(b)))

user = input()
a, b = list(map(int, user[0::2])), list(map(int, user[1::2]))
print(abs(sum(a) - sum(b)))
