using System;
using static System.Math;

public class Program
{
    public static void Main(string[] args)
    {
        var x = int.Parse(Console.ReadLine());
        var y = int.Parse(Console.ReadLine());
        var step = int.Parse(Console.ReadLine());
        int  rotCnt;

        var move_x = Abs((x / step)) + Abs((x % step));
        var move_y = Abs((y / step)) + Abs((y % step));

        if (x < 0 && y < 0) rotCnt = 2;
        else if (x < 0 && y > 0) rotCnt = 1;
        else if (x > 0 && y > 0) rotCnt = 1;
        else if (x > 0 && y < 0) rotCnt = 2;
        else if (x == 0 && y < 0) rotCnt = 2;
        else if (x != 0 && y == 0) rotCnt = 1;
        else rotCnt = 0;

        Console.WriteLine(move_x + move_y + rotCnt);
    }
}