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.math.BigInteger;
import java.util.*;

public class A {

    public static void collect(StringBuilder v, Set<String> uniq) {
        String asString = v.toString();
        if (uniq.contains(asString)) {
            return;
        }
        uniq.add(asString);
        System.out.println(asString);

        int carry = 0;
        boolean add = true;
        for (int i = v.length() - 1; i >= 0; --i) {
            int n = (v.charAt(i) - '0') + carry;
            if (add) {
                n = n + 1;
                add = false;
            }

            int reminder = n % 10;
            if (reminder == 0 && v.length() - 1 == i) {
                v.deleteCharAt(i);
            } else {
                v.setCharAt(i, (char) (reminder + '0'));
            }

            carry = n / 10;
        }

        if (carry > 0) {
            assert(carry < 10);
            v.insert(0, (char) (carry % 10 + '0'));
        }

        collect(v, uniq);
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        BigInteger in = new BigInteger(scanner.nextLine());
        scanner.close();

        Set<BigInteger> uniq = new HashSet<>();
//        collect(n, uniq);
        while (!uniq.contains(in)) {
            uniq.add(in);

            in = in.add(BigInteger.valueOf(1));
            while (in.mod(BigInteger.valueOf(10)).intValue() == 0) {
                in = in.divide(BigInteger.valueOf(10));
            }
        }
        System.out.println(uniq.size());
//        System.out.println("==");
//        System.out.println(Arrays.toString(uniq.toArray()));
    }
    
}
