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 % 10) == 0) {
      System.out.println(10);
    } else {
      String s = Integer.toString(n);
      int ans = 0;
      for (int i = 0; i < s.length(); i++) {
        ans += Character.getNumericValue(s.charAt(i));
      }
      System.out.println(ans);
    }

  }
}