// No.275 中央値を求めよ
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

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) {
        cout << A[N / 2] << endl;
    } else {
        cout << (double)(A[N / 2] + A[N / 2 - 1]) / 2 << endl;
    }
}