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

using namespace std;

int main(int argc, char const* argv[]) {
    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 << (A[N/2] + A[N/2-1]) * 0.5 << endl;
    } else {
        cout << A[N/2] << endl;
    }
    return 0;
}