using System;

    class Program
    {
        static void Main(string[] args)
        {
            Double a = Double.Parse(Console.ReadLine());
            Double b = Double.Parse(Console.ReadLine());
            Double c = Double.Parse(Console.ReadLine());
            Double d = Double.Parse(Console.ReadLine());
            var s = (a + b + c + d)/2;

            if (a > b) Swap(ref a, ref b);

            if (b > c) Swap(ref b, ref c);
            if (a > c) Swap(ref a, ref c);

            if (a > d) Swap(ref a, ref d);
            if (b > d) Swap(ref b, ref d);
            if (c > d) Swap(ref c, ref d);

            if (s > 0)
            {
                var mpn = 0.0;
                if (a > 0) mpn = a;
                else if (b > 0) mpn = b;
                    else if (c > 0) mpn = c;
                        else if (d > 0) mpn = d;
                            else throw new Exception("!!!!!!");
                Console.WriteLine(mpn*mpn);        

            }
            else
            {
                if (a < 0) a -= d;
                if (b < 0) b -= d;
                if (c < 0) c -= d;
                if (d < 0) d -= d;
                Console.WriteLine(a);
                Console.WriteLine(b);
                Console.WriteLine(c);
                Console.WriteLine(d);
            }
           
        }

        private static void Swap(ref double a, ref double b)
        {
            var tmp = a;
            a = b;
            b = tmp;
        }
    }