import java.util.Arrays;
import java.util.Scanner;

public class Yuki275 {
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		double[] arr = new double[N];

		for(int i = 0; i < N; i++){
			arr[i] = scan.nextDouble();
		}

		Arrays.sort(arr);

		double median = 0.0;
		if(N % 2 == 0){
			median = (arr[(N/2) - 1] + arr[N/2]) / 2;
		}else{
			median = Math.ceil(arr[N/2]);
		}
		System.out.printf("%.1f", median);
	}
}