#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <stdio.h>
#include <cstring>
#include <queue>
#include <stack>
#include <functional>
#include <math.h>
#include <iomanip>
using namespace std;
#define Would
#define you
const int INF = 999999999;
const int MOD = 1e9 + 7;

int main() {
	int n, k[1005];
	cin >> n;
	for (int i = 0; i < n; ++i) { cin >> k[i]; }
	sort(k, k + n);
	if (n % 2 == 1) {
		cout << k[n / 2] << endl;
		return 0;
	}
	cout << (double)(k[n / 2] + k[n / 2 - 1]) / 2 << endl;
}