Project Euler #34: Digit factorials | Hackerrank | Project Euler

 Digit factorials 

19 is a curious number, as 1!+9!=1+362880=362881 which is divisible by 19.

Find the sum of all numbers below N which divide the sum of the factorial of their digits.

Note: as 1!,2!,...,9! are not sums they are not included.

Input Format

Input contains an integer N

Constraints

10<=N<=10^5

Output Format

Print the answer corresponding to the test case.

Sample Input

20

Sample Output

19

Solution:

#include <cmath>

#include <cstdio>

#include <vector>

#include <iostream>

#include <algorithm>

using namespace std;

int main() {

    long long n;

    scanf("%lld",&n);

    long long total=0;

    for(long long i=10;i<=n;i++)

    {

        long long m,k,sum=0;

        k=i;

        while(k>0)    

         {   

         long long fact=1;

         m=k%10; 

         if(m==0)

         fact=1;

         else{

         for(long long j=1;j<=m;j++)  

         fact*=j;

         }

         sum+=fact;

         k=k/10;

         }

         //cout<<sum<<endl;

         if(sum%i==0)

          total+=i;

    }

     cout<<total;

    return 0;

}

You can also run it on an online IDE :

https://ide.geeksforgeeks.org/d823a9e4-936e-4127-b9e9-21a8aef2a7f0

Your feedback are always welcome! If you have any doubt you 

can contact me or leave a comment!  

Happy Coding!! Cheers!!!