#include <bits/stdc++.h>
using namespace std;
int n;
int main(void){
    cin >> n;
    int sum = 0;
    while(n>0){
        sum += n % 10;
        n /= 10;
    }
    if(sum == 1){
        cout<<10<<endl;
    }else{
        cout<<sum;
    }
}

### Prompt

Create a solution in Cpp for the following problem:

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".

Examples

Input

15


Output

6


Input

100000


Output

10

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
int n;
int main(void){
    cin >> n;
    int sum = 0;
    while(n>0){
        sum += n % 10;
        n /= 10;
    }
    if(sum == 1){
        cout<<10<<endl;
    }else{
        cout<<sum;
    }
}

```