using System;
using System.Collections.Generic;
using System.Linq;
using System.Numerics;
using static System.Math;

namespace SortItems
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = Console.ReadLine().Split().Select(double.Parse).ToArray();
            double cnt = 0.00;

            Array.Sort(n);

            for (var i = 1; i < n.Length - 1; i++)
            {
                cnt += n[i];
            }

            

            Console.WriteLine(string.Format("{0:0.00}", cnt / (n.Length-2)));
            


        }
    }
}