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);

    String N = sc.next();
    int ans = 0;
    for (int i = 0; i < N.length(); i++) {
      char n = N.charAt(i);
      ans += Integer.valueOf(String.valueOf(n));
    }
    if (ans == 1) {
      ans = 10;
    }
    System.out.println(ans);
  }
}