#include <iostream>
#include <vector>
#include <string>
#include <algorithm>

using namespace std;
typedef long long int lint;

int main()
{
	lint N, tmp;
	vector<lint> A;

	cin >> N;
	for (lint i = 0; i < N; i++) {
		cin >> tmp;
		A.push_back(tmp);
	}

	sort(A.begin(), A.end());

	if (N % 2 == 1)
		cout << A[N / 2] << endl;
	else
		cout << (double)(A[N / 2 - 1] + A[N / 2]) / 2 << endl;

	return 0;
}