#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define endl "\n"

int main() {
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }

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

    return 0;
}