using System;
using System.Collections.Generic;

public class yukicoder{
    
    public static int move(int n)
    {
        string s = Convert.ToString(n, 2);
        int m = 0;
        
        foreach(char c in s)
        {
            if(char.IsNumber(c))
            {
                m += int.Parse(c.ToString());
            }
        }
        
        return m;
    }
    
    public static void Main(){
        int goal = int.Parse(Console.ReadLine());
        int[] board = new int[goal];
        List<int> usedcell = new List<int>();
        
        for(int i = 0; i < board.Length; i++)
        {
            board[i] = i + 1;
        }
        
        int now = 1;
        
        while(true)
        {
        	usedcell.Add(now);
        
            if(now == goal)
            {
                Console.WriteLine(usedcell.Count);
                break;
            }

			if((now + move(board[now - 1])) > goal)
			{
				now -= move(board[now - 1]);
				
				if(usedcell.Contains(now))
				{
					Console.WriteLine(-1);
					break;
				}
			} 
			else
			{
				now += move(board[now - 1]);
			}
	       
        }

    }
}