using System;

namespace console_aplication54
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            string[] nm = Console.ReadLine().Split(' ');
            if (int.Parse(nm[0]) >= 1 && int.Parse(nm[1]) <= 1000)
            {
                double x,y;
                x = double.Parse(nm[0]);
                y = double.Parse(nm[1]);
                Console.Write(Convert.ToInt32(Math.Ceiling(x*2)/y));
            }
        }
    }
}