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 Day2_4_ReachableNumbers {

	public static void main(String[] args) {
		InputReader reader = new InputReader(System.in);
		int n = reader.nextInt();
		boolean repeat = false;
		List<Integer> num = new ArrayList<>();
		num.add(n);
		int count = 1;
		while (!repeat) {
			n++;
			String number = String.valueOf(n);
			for (int i = number.length() - 1; i >= 0; i--) {
				String current = number.charAt(i) + "";
				if (current.equals("0"))
					n = n / 10;
				else {
					if (!num.contains(n)) {
						num.add(n);
						count++;
					} else
						repeat = true;
					break;
				}
			}
		}
		System.out.print(count);
	}

	static class InputReader {
		StringTokenizer tokenizer;
		BufferedReader reader;
		String token;
		String temp;

		public InputReader(InputStream stream) {
			tokenizer = null;
			reader = new BufferedReader(new InputStreamReader(stream));
		}

		public InputReader(FileInputStream stream) {
			tokenizer = null;
			reader = new BufferedReader(new InputStreamReader(stream));
		}

		public String nextLine() throws IOException {
			return reader.readLine();
		}

		public String next() {
			while (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					if (temp != null) {
						tokenizer = new StringTokenizer(temp);
						temp = null;
					} else {
						tokenizer = new StringTokenizer(reader.readLine());
					}
				} catch (IOException e) {
				}
			}
			return tokenizer.nextToken();
		}

		public double nextDouble() {
			return Double.parseDouble(next());
		}

		public int nextInt() {
			return Integer.parseInt(next());
		}

		public long nextLong() {
			return Long.parseLong(next());
		}
	}

}
