import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader stdReader =new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(stdReader.readLine());
		String[] temps = stdReader.readLine().split(" ");
		int[] nums = new int[temps.length];
		for(int i=0;i<nums.length;i++){
			nums[i] = Integer.parseInt(temps[i]);
		}
		Arrays.sort(nums);
		
		if(nums.length%2!=0){
			System.out.println(nums[nums.length/2]);
		}else{
			System.out.println((double)(nums[nums.length/2]+nums[(nums.length/2)-1])/2);
		}
	}
}