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) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner scanner = new Scanner(System.in);
		char[] n = String.valueOf(scanner.nextInt()).toCharArray();
		int ans = 0;
		for(int i = 0; i < n.length; i++) {
			if(n[0] == '1' && n[1] == '0' && i == 0 ) {
				ans += (n[i] - '0') * 10;
			}else {
				ans += n[i] - '0';
			}
		}		
		System.out.println(ans);
	
	}

}