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();
    
    int count = 0;
    if( N == 10 || N == 100 || N ==1000 || N == 10000 || N == 100000 ){
      System.out.println(10);
      return;
    }
    
      while( N > 0 ){
        count += N%10;
        N /= 10;
      }
    System.out.println(count);
  }
}

      