def f(n):
    s = ""
    while n > 0:
        s += str(n % 25)
        n //= 25
    s = s[::-1]
    return s

n = 3 * 3125**9 + 2 * 625**8 - 4 * 625**7 + 3 * 125**6 - 2 * 25**5 - 2024
n = f(n)
print(n.count('0'))