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

int main(void){
    int n;
    cin >> n;
    int s=0;
    while(n>0){
        s+=n%10;
        n/=10;
    }
    if(s==1){
        cout << 10 << endl;
    }else{
        cout << s << endl;
    }
    return 0;
}

### Prompt

Please create a solution in CPP to 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 main(void){
    int n;
    cin >> n;
    int s=0;
    while(n>0){
        s+=n%10;
        n/=10;
    }
    if(s==1){
        cout << 10 << endl;
    }else{
        cout << s << endl;
    }
    return 0;
}

```