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.Arrays;
import java.util.Scanner;

public class Main {

	private static Scanner sc = new Scanner(System.in);

	public static void main(String[] args) {
		String[] n = sc.next().split("");
		int sum = Arrays.stream(n)
				.mapToInt(Integer::parseInt)
				.sum();
		System.out.println(sum == 1 ? 10 : sum);
	}
}