using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp3
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Вводите");
            String a = Console.ReadLine();
            Char b = ' ';
            String[] c = a.Split(b);
            int z = 0;
            double y = 0;
            double x = 0;
            double k = 0;

            while (z<c.Length)
            {

                if (Char.IsNumber(c[z],0)== true)
                {
                    x = Convert.ToDouble(c[z]);
                    y = y + x;
                    k = k + 1;
                }
                z = z + 1;
            }
            Console.WriteLine(y*10 / k);
        }
    }
}