#include<iostream>

using namespace std;

int main() {
	unsigned int N = 0;
	unsigned int min = 0;
	cin >> N;

	while (1) {
		min += N % 10;
		N /= 10;
		if (N == 0) break;
	}

	if (min == 1) min *= 10;
	cout << min << endl;
	return 0;
}
### Prompt

Please formulate 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<iostream>

using namespace std;

int main() {
	unsigned int N = 0;
	unsigned int min = 0;
	cin >> N;

	while (1) {
		min += N % 10;
		N /= 10;
		if (N == 0) break;
	}

	if (min == 1) min *= 10;
	cout << min << endl;
	return 0;
}
```