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

int main(){
  int N;
  cin >> N;
  int ans=0;
  while(N!=0){
    ans+=N%10;
    N=N/10;
  }
  if(ans==1) cout << 10 << endl;
  else cout << ans << endl;
}
### 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>
#include <iostream>
using namespace std;

int main(){
  int N;
  cin >> N;
  int ans=0;
  while(N!=0){
    ans+=N%10;
    N=N/10;
  }
  if(ans==1) cout << 10 << endl;
  else cout << ans << endl;
}
```