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

using namespace std;

static void setup()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
}

static void run()
{
    int n;
    cin >> n;

    vector<int> as;
    as.resize(n);
    for (auto i = 0; i < n; ++i) {
        cin >> as[i];
    }

    sort(begin(as), end(as));
    if (n % 2 == 0) {
        cout << (as[n / 2 - 1] + as[n / 2]) / 2.0f << endl;
    }
    else {
        cout << as[n / 2] << endl;
    }
}

int main(int argc, char **argv)
{
    setup();
    run();
    return 0;
}