n = input()
count = 0
for digit in n:
    if digit == '0':
        count += 1
print(count)

090f25741f6a3474f7f93329ff08894f3f8a8f19
<mask token>

<mask token>
for digit in n:
    if digit == '0':
        count += 1
print(count)

n = input()
count = 0
for digit in n:
    if digit == '0':
        count += 1
print(count)
