using System;
public class Hello{
    public static void Main(){
       
        string[] inpt = Console.ReadLine().Split();
        var points = Array.ConvertAll(inpt, int.Parse);
        
        Array.Sort(points);
        
        float validP  = 0;
        
        for(int i=1;i<points.Length-1;i++)
            validP+=points[i];
            
        float ans = (validP / (points.Length - 2));
        
        Console.WriteLine(ans.ToString("F2"));
        
    }
}