#include <iostream>
#include <cstdio>
using namespace std;

int n, s;
int main()
{
	cin >> n;
	for (; n; n /= 10) s += n % 10;
    cout << (s < 2 ? 10 : s) << endl;
    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 <iostream>
#include <cstdio>
using namespace std;

int n, s;
int main()
{
	cin >> n;
	for (; n; n /= 10) s += n % 10;
    cout << (s < 2 ? 10 : s) << endl;
    return 0;
}
```