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

class Failipunktid
{
    public static void Main(string[] arg)
    {
          Console.WriteLine(File.ReadAllLines("punktid.txt").Select(p => double.Parse(p))
		      .OrderBy(p => p).Skip(1).Take(3).Average());
    }
}
/*
E:\jaagup\11\09\linq>type punktid.txt
16,3
16,2
17,4
12,5
14,3

E:\jaagup\11\09\linq>Failipunktid
15,6
*/