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: Wrong Answer)

#include<iostream>
#include<algorithm>
using namespace std;

int main() {
    int n;
    cin>>n;
    int mins=10000;
    int a,b;
    for(int i=1; i<n-1; i++) {
        a=i;
        b=n-i;
        int sum=0;
        for(int k=0; k<6; k++) {
            sum += a%10+b%10;
            a /= 10;
            b /= 10;
        }
        mins = min(mins, sum);
    }
    cout<<mins<<endl;
}