using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        double[] S = Console.ReadLine().Split(' ').Select(s => double.Parse(s)).ToArray();

        Console.WriteLine(((S.Sum() - S.Min() - S.Max()) / (double)(S.Length - 2)).ToString("0.00"));
    }
}