#include <bits/stdc++.h>
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 == 1) {
    cout << a[0] << endl;
  }
  else if (n & 1) {
    cout << a[n / 2] << endl;
  }
  else {
    cout << (double)(a[n / 2] + a[n / 2 - 1]) / 2 << endl;
  }
  return 0;
}