#include <cstdio>

int main() {
    int n;
    scanf("%d", &n);

    int ans = 0;
    while (n > 0) {
        ans += n % 10;
        n /= 10;
    }
    if (ans == 1) { ans = 10; }
    printf("%d\n", ans);
    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 <cstdio>

int main() {
    int n;
    scanf("%d", &n);

    int ans = 0;
    while (n > 0) {
        ans += n % 10;
        n /= 10;
    }
    if (ans == 1) { ans = 10; }
    printf("%d\n", ans);
    return 0;
}
```