#include <iostream>

int main()
{
    std::ios_base::sync_with_stdio(false);
    int N, ans = 0;
    std::cin >> N;
    while (N > 0) {
        ans += N % 10;
        N /= 10;
    }
    std::cout << (ans != 1 ? ans : 10) << std::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>

int main()
{
    std::ios_base::sync_with_stdio(false);
    int N, ans = 0;
    std::cin >> N;
    while (N > 0) {
        ans += N % 10;
        N /= 10;
    }
    std::cout << (ans != 1 ? ans : 10) << std::endl;
    return 0;
}

```