Problem:
Score : 200 points

Problem Statement

Takahashi has two positive integers A and B.

It is known that A plus B equals N.
Find the minimum possible value of "the sum of the digits of A" plus "the sum of the digits of B" (in base 10).

Constraints

2 ≤ N ≤ 10^5

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

Print the minimum possible value of "the sum of the digits of A" plus "the sum of the digits of B".

Sample Input 1

15

Sample Output 1

6

When A=2 and B=13, the sums of their digits are 2 and 4, which minimizes the value in question.

Sample Input 2

100000

Sample Output 2

10

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

int main()
{
    int n,m[5],l;
    cin>>n;
    l=n;
    for(int i=0;i<5;i++){
        m[i]=l%10;
        l=l/10;
    }
    if(n==10||n==100||n==1000||n==10000||n==100000){
        m[0]=10; m[1]=0; m[2]=0; m[3]=0; m[4]=0;
    }
    cout<<m[0]+m[1]+m[2]+m[3]+m[4]<<endl;
    return 0;
}