#!/usr/bin/env python3
"""
Created on 15 Sep 2018

@author: David Doblas Jiménez
@email: daviddoji@pm.me

Solution for problem 20 of Project Euler
https://projecteuler.net/problem=20
"""

from math import factorial
from utils import timeit


@timeit("Problem 20")
def compute():
    """
    n! means n × (n − 1) × ... × 3 × 2 × 1
    
    For example, 10! = 10 × 9 × ... × 3 × 2 × 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!
    """
    fact = factorial(100)
    sum_digits = sum(int(digit) for digit in str(fact))
    
    return sum_digits 


if __name__ == "__main__":

    print(f"Result for Problem 20: {compute()}")