using System; using System.Collections.Generic; class Program { static void Main(string[] args) { var N = int.Parse(Console.ReadLine()); var input = Console.ReadLine().Split(' '); var list = new List(); int midIdx; foreach (var d in input) { list.Add(int.Parse(d)); } list.Sort(); if (N % 2 == 0) { midIdx = N / 2; Console.WriteLine("{0:f1}", (list[midIdx - 1] + list[midIdx]) / 2.0); } else { midIdx = N / 2; Console.WriteLine("{0:f1}", list[midIdx]); } } }