import java.util.*;
import java.math.*;

public class pre {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		int num[] = new int[n];
		
		for(int i=0;i<num.length;i++){
			num[i] = s.nextInt();
		}
		
		Arrays.sort(num);
		
		if(n%2==1)
			System.out.println(num[n/2]);
		else
			System.out.printf("%.1f\n",(double)(num[n/2]+num[n/2-1])/2);
		
    }
}