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

Your challenge is to write a cpp solution 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<iostream>
#include<string>
#include<vector>
using namespace std;
int main(){
  int N;
  cin >> N;
  int tmp=N;
  int ans=0;
  while (tmp!=0){
    ans+=tmp%10;
    tmp=tmp/10;
  }
  if(ans==1){
    ans=10;
  }
  cout <<ans;
  return 0;
}
```