using System.Collections.Generic;
using System;
using System.Drawing;
namespace yukicoder
{
    class Program
    {

        static void Main(string[] args)
        {
            var S = Console.ReadLine().Split(" ");
            List<int> list = new List<int>();
            double sum = 0;
            for(int i = 0; i < S.Length; i++)
            {
                list.Add(int.Parse(S[i]));
            }

            list.Sort();

            list.Remove(list[0]);
            list.Remove(list[list.Count - 1]);

            for(int j = 0; j < list.Count; j++)
            { 
                double n = list[j] ;
                sum += list[j];
            }
            double ans = sum / list.Count;
            if (sum % list.Count == 0)
            {
                Console.WriteLine((double)ans + ".00");
            }
            else
            {
                Console.WriteLine((double)ans);
            }
            
            
        }
    }
}