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.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();

        if(n == 100000 || n == 10000 || n == 1000 || n == 100 || n == 10 ){
            System.out.println(10);
            return;
        }

        int sum = 0;
        int a = 0;
        while (n > 0){
            a = n % 10;
            n = n / 10;
            sum += a;
        }


        System.out.println(sum);
    }
}
