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.*;
import java.lang.Math;
public class Solution {
    public static int beautifulFunction(int N){
        HashSet<Integer> hs = new HashSet<Integer>() ; 
        HashSet<Integer> inserted = new HashSet<Integer>();
        String temp = String.valueOf(N);
        if(temp.length()==1)
        {
           return 9;    
        }
        else 
        {
           inserted.add(N) ; 
           boolean flag = false; 
            hs.add(N);
            if(N%10==0)
            {
                flag = true ; 
                N = N + 10 ; 
            }
            else
            {
                flag = false;  
            }
            while(true)
            {
                if(N%10!=0)
                {
                    if((N+1)%10!=0)
                    {
                        inserted.add(N+1); 
                        N++ ; 
                    } 
                    else
                    {
                         String  temp1 = String.valueOf(N+1);
                         String temp2 = temp1.replaceFirst("^0*", "").replaceFirst("0*$", "");
                         int alsoFind = Integer.valueOf(temp2) ; 
                        
                         inserted.add(alsoFind);
                         N = alsoFind ; 
                         if(hs.contains(alsoFind))
                         {
                            if(flag) 
                                return inserted.size()+9;
                            else
                                return inserted.size();
                         }
                         hs.add(alsoFind);
                    }
                }
                else
                {
                         String  temp1 = String.valueOf(N);
                         String temp2 = temp1.replaceFirst("^0*", "").replaceFirst("0*$", "");
                         int alsoFind = Integer.valueOf(temp2) ; 
                         inserted.add(alsoFind);
                         N = alsoFind ; 
                    
                         if(hs.contains(alsoFind))
                         {
                           if(flag) 
                                return inserted.size()+9;
                            else
                                return inserted.size();
                         }
                         hs.add(alsoFind);
                }
            }
            
           
        }
      
        
    }

    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        int N;
        N=scan.nextInt();
        int result;
        result = beautifulFunction(N);
        System.out.print(result);
        return ;
    }
}