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

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

Generate 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;

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