using System;

class Q0275
{
	public static void Main()
	{
		int n = int.Parse(Console.ReadLine());

		string[] num = Console.ReadLine().Split(' ');
		int[] a = new int[n];
		for (int i=0; i<n; i++)
		{
			a[i] = int.Parse(num[i]);
		}

		Array.Sort(a);

		float output;
		if(n%2 > 0)
		{
			output = a[n/2];
		}
		else
		{
			output = (float)(a[n/2] + a[n/2-1])/2;
		}

		Console.WriteLine(output);
	}
}