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

using namespace std;

int main() {
    int N;
    cin >> N;

    double A = 0;

    vector<double> A_N;
    for (int i = 0; i < N; i++) {
        cin >> A;
        A_N.push_back(A);
    }

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

    if (N % 2 == 1) {
        cout << A_N[N / 2];
    } else {
        cout << (A_N[(N / 2) -1] + A_N[N / 2]) / 2;
    }
    return 0;
}