Let's denote a function f(x) in such a way: we add 1 to x, then, while there is at least one trailing zero in the resulting number, we remove that zero. For example, 

  * f(599) = 6: 599 + 1 = 600 → 60 → 6; 
  * f(7) = 8: 7 + 1 = 8; 
  * f(9) = 1: 9 + 1 = 10 → 1; 
  * f(10099) = 101: 10099 + 1 = 10100 → 1010 → 101. 



We say that some number y is reachable from x if we can apply function f to x some (possibly zero) times so that we get y as a result. For example, 102 is reachable from 10098 because f(f(f(10098))) = f(f(10099)) = f(101) = 102; and any number is reachable from itself.

You are given a number n; your task is to count how many different numbers are reachable from n.

Input

The first line contains one integer n (1 ≤ n ≤ 10^9).

Output

Print one integer: the number of different numbers that are reachable from n.

Examples

Input


1098


Output


20


Input


10


Output


19

Note

The numbers that are reachable from 1098 are:

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 1098, 1099.
import java.io.*;
import java.util.*;

public class Main {

    public static void main(String[] args) throws IOException {
//        br = new BufferedReader(new FileReader(new File("input.txt")));
//        out = new PrintWriter(new File("output.txt"));
        int nasral = 1;
        for (int JOPA = 0; JOPA < nasral; JOPA++) {
            int n = nextInt();
            TreeSet<Integer> have= new TreeSet<>();
            for (int i = 0; i < 1000; i++) {
                have.add(n);
                n ++;
                while (n % 10 == 0)n /= 10;
            }
            out.println(have.size());

            
        }
        out.close();

    }


    public static StringTokenizer in = new StringTokenizer("");
    public static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    public static PrintWriter out = new PrintWriter(System.out);

    public static String next() throws IOException {
        while (!in.hasMoreTokens()) {
            in = new StringTokenizer(br.readLine());
        }
        return in.nextToken();
    }

    public static Integer nextInt() throws IOException {
        return Integer.parseInt(next());
    }

    public static Long nextLong() throws IOException {
        return Long.parseLong(next());
    }
}
