using System;

public class Hello
{
    public static void Main()
    {
        var n = int.Parse(Console.ReadLine().Trim());
        string[] line = Console.ReadLine().Trim().Split(' ');
        var a = Array.ConvertAll(line, int.Parse);
        Array.Sort(a);
        double ans;
        ans = n % 2 == 0 ? (a[n / 2] + a[n / 2 - 1]) / 2d : a[(n - 1) / 2];
        Console.WriteLine(ans);
    }
}