sol1.py

"""
Problem 20: https://projecteuler.net/problem=20

n! means n x (n - 1) x ... x 3 x 2 x 1

For example, 10! = 10 x 9 x ... x 3 x 2 x 1 = 3628800,
and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27.

Find the sum of the digits in the number 100!
"""


deffactorial(num: int) ->int:
"""Find the factorial of a given number n"""
fact=1
foriinrange(1, num+1):
fact*=i
returnfact


defsplit_and_add(number: int) ->int:
"""Split number digits and add them."""
sum_of_digits=0
whilenumber>0:
last_digit=number%10
sum_of_digits+=last_digit
number=number//10# Removing the last_digit from the given number
returnsum_of_digits


defsolution(num: int=100) ->int:
"""Returns the sum of the digits in the factorial of num
 >>> solution(100)
 648
 >>> solution(50)
 216
 >>> solution(10)
 27
 >>> solution(5)
 3
 >>> solution(3)
 6
 >>> solution(2)
 2
 >>> solution(1)
 1
 """
nfact=factorial(num)
result=split_and_add(nfact)
returnresult


if__name__=="__main__":
print(solution(int(input("Enter the Number: ").strip())))