from sys import argv def fact(n): res = 1 for i in range(2, n+1): res *= i return res def num_trailing_zeros(n): cnt = 0 pwr = 10 while n % pwr == 0: cnt += 1 pwr *= 10 return cnt n = int(argv[1]) f = fact(n) z = num_trailing_zeros(f) zeros = "zero" if z == 1 else "zeros" print(f"{n} as N! = {f} has {z} trailing {zeros}")