#include <bits/stdc++.h>

using namespace std;

char str[10];

int main()
{
    cin>>str;
    int sum=0;
    int len=strlen(str);
    for(int i=0;i<len;i++)
    {
        sum+=str[i]-48;
    }
    if(sum==1) sum*=10;
    cout<<sum<<endl;
    return 0;
}

### Prompt

Please formulate 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 <bits/stdc++.h>

using namespace std;

char str[10];

int main()
{
    cin>>str;
    int sum=0;
    int len=strlen(str);
    for(int i=0;i<len;i++)
    {
        sum+=str[i]-48;
    }
    if(sum==1) sum*=10;
    cout<<sum<<endl;
    return 0;
}

```