using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

class Program
{
    static void Main(string[] args)
    {
        //var data = "-50 -40 30";
        var data = Console.ReadLine();
        var expect = 133;

        Action<string> nullFunc = (msg) => { };
        Action<string> outDebug = Console.WriteLine;
        //Action<string> output = outDebug;
        Action<string> output = nullFunc;

        var tbl = new Dictionary<bool, string>
        {
            { true,  "〇" },
            { false, "×" }
        };

        //var ret = tbl[expect == Solve(data)];
        //outDebug(ret);

        Console.WriteLine(Solve(data));

        //Console.ReadLine();
    }

    static int Solve(string data)
    {
        var e = data.Split(' ');
        var x = Math.Abs(int.Parse(e[0]));
        var y = Math.Abs(int.Parse(e[1]));
        var r = int.Parse(e[2]);

        // UFOの最も遠いマンハッタン距離は？

        var s = x + y + (int)Math.Ceiling(Math.Sqrt(2)*r);

        return s;
    }
}