using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        decimal N = decimal.Parse(Console.ReadLine());
        decimal num = 0;
        decimal max = 0;

        decimal std = 0;
        do
        {
            std += N;

            num = std + N;
            if (max < num) { max = num; }

            N = Math.Floor(N / 2);
        } while (0 < N);

        Console.WriteLine(max - std);
    }
}