//Rextester.Program.Main is the entry point for your code. Don't change it.

//Microsoft (R) Visual C# Compiler version 2.9.0.63208 (958f2354)

​

using System;

​

​

namespace ConsoleApp

{

    public class Program

    {

        public static void Main(string[] args)

        {

            int num = Convert.ToInt32(Console.Readline()); int count = 1;

            while(num!=0)

            {

                num = num +  Convert.ToInt32(Console.Readline());

                count++;

            }

            Console.WriteLine(num/count);

        }

    }

}