package yukiCoder;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;

public class No00275 {

	public static void main(String[] args) {
		BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

		try {
			int index = Integer.parseInt(bufferedReader.readLine());
			String[] input = new String[index];
			input = bufferedReader.readLine().split(" ");

			int[] intArray = toIntArray(input);
			Arrays.sort(intArray);
			System.out.println(median(intArray));
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

	public static int[] toIntArray(String[] stringArray) {
		int[] intArray = new int[stringArray.length];
		for (int i = 0 ; i < stringArray.length ; i++) {
			intArray[i] = Integer.parseInt(stringArray[i]);
		}
		return intArray;
	}

	public static double median(int[] intArray) {
		int center1 = intArray.length/2;
		if(intArray.length%2 == 0) {
			int center2 = center1 - 1;
			return (intArray[center1] + intArray[center2]) / 2d;
		}
		return intArray[center1];
	}

}