import java.util.Arrays;
import java.util.Scanner;
public class Main {

    public static void main(String[] args) {
	    Scanner sc = new Scanner(System.in);

            int a = sc.nextInt();
            double []b = new double[a];
            for (int i=0;i<a;i++){
                b[i]=sc.nextInt();
            }
            Arrays.sort(b);
            if (a%2==1){
                System.out.println(b[a%2]);
            }else {
                System.out.println((b[a/2]+b[a/2-1])/2);
        }
    }
}