#include <string>
#include <iostream>
using namespace std;
int main() {
	string s;
	cin >> s;
	int ans = 0;
	for (int i = 0; i < s.size(); ++i) {
		ans += int(s[i] - '0');
	}
	if (ans <= 1) cout << ans + 9 << endl;
	else cout << ans << endl;
	return 0;
}
### Prompt

Your challenge is to write 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 <string>
#include <iostream>
using namespace std;
int main() {
	string s;
	cin >> s;
	int ans = 0;
	for (int i = 0; i < s.size(); ++i) {
		ans += int(s[i] - '0');
	}
	if (ans <= 1) cout << ans + 9 << endl;
	else cout << ans << endl;
	return 0;
}
```