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

### Prompt

Please provide a CPP coded solution to the problem described below:

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

```