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

int main() {
	int n,ans=0;cin>>n;
  	while(n>0){
    	ans+=n%10;
      	n/=10;
    }
  	if(ans==1){
    	cout<<10<<endl;
    }else{
    	cout<<ans<<endl;
    }
}
### Prompt

Construct a CPP code solution to the problem outlined:

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;
#define ll long long

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