Untitled

def F(n):
    if n < 10:
        return n
    elif n % 2 == 0:
        return F(n % 10) + F(n // 10)
    else:
        return F(10**n) + F(n % 10) - 2


counter = 0
for i in range(10*11):
    if F(i) == 0:
        counter += 1

print(counter)