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

int main() {
  string s;
  cin >> s;

  int sum = 0;
  for (int i = 0; i < s.size(); i ++) {
    sum += s.at(i) - '0';
  }

  if (sum == 1) {
    cout << 10 << endl;
  } else {
    cout << sum << endl;
  }
}

### Prompt

Your task is to create 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() {
  string s;
  cin >> s;

  int sum = 0;
  for (int i = 0; i < s.size(); i ++) {
    sum += s.at(i) - '0';
  }

  if (sum == 1) {
    cout << 10 << endl;
  } else {
    cout << sum << endl;
  }
}

```