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

}

### 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;
int n,m;
int main(){
    cin>>n;
    int s=0;
    m=n;
    while(m){
        s+=m%10;
        m/=10;
    }
    if(s>1 ||( s==1 && n==1))
        cout<<s;
    else
        cout<<10;
        return 0;

}

```