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
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        if (n == 10 || n == 100 || n == 1000 || n == 10000 || n == 100000 || n == 1000000) {
            System.out.println(10);
        } else {
            int res = 0;
            while ( n > 0) {
                res += n%10;
                n/=10;
            }
            System.out.println(res);
        }
    }
}
