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[]srgs) {
	Scanner scan=new Scanner(System.in);
	int a=scan.nextInt();
	if(a%10==0) {
		System.out.println(10);
	}
	else {
		int ans=0;
		for(int i=0;i!=10;i++) {
			ans+=a%10;
			a/=10;
		}
		System.out.println(ans);
	}
	}
}