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

int main() {
	int N;
	cin >> N;
	int x = 0;
	while(N != 0){
		x += N % 10;
		N /= 10;
	}
	if(x == 1){
		cout << 10 << endl;
		return 0;
	}
	cout << x << endl;
}
### Prompt

Construct a CPP code solution to the problem outlined:

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;
	int x = 0;
	while(N != 0){
		x += N % 10;
		N /= 10;
	}
	if(x == 1){
		cout << 10 << endl;
		return 0;
	}
	cout << x << endl;
}
```