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

public class Main{
	public static void main(String[] args) {
//		int[] a1 = {1, 5, 2, 4, 7};
//		int[] a2 =new int[a1.length];
//		System.arraycopy(a1, 0, a2, 0, a1.length);
//		BubbleSort bs = new BubbleSort(a1);
//		bs.getArrayAsc();
//		for(int i = 0; i < a1.length; i++) {
//			System.out.println(a1[i] + "/" + a2[i]);
//		}
		//System.out.println("数字の数");
		Scanner scanner = new Scanner(System.in);
		int N = scanner.nextInt();
		int array[] = new int[N];
		for(int i = 0; i < N; i++) {
			array[i] = scanner.nextInt();
		}
		scanner.close();
		//BubbleSort bs = new BubbleSort(array);
		//int[] array1 = bs.getArrayAsc();
		Arrays.sort(array);
		if(N % 2 ==0) {
			double ans = (double)(array[N/2-1]+array[N/2])/2;
			System.out.println(ans);
		}else {
			System.out.println(array[(N+1)/2-1]);
		}
	}
}