#include <bits/stdc++.h>
using namespace std;

int main()
{
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; i++) cin >> a.at(i);
    sort(a.begin(), a.end());
    if (n % 2 == 1) {
        cout << a.at(n / 2) << endl;
    } else {
        cout << 0.5 * (a.at(n / 2) + a.at(n / 2 - 1));
    }
}