#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, tmp;
  cin >> n;
  double sum = 0;
  vector<double> hoge;
  for (int i = 0; i < n; i++) {
    cin >> tmp;
    hoge.push_back(tmp);
  }
  sort(hoge.begin(), hoge.end());
  for (int i = 0; i < hoge.size(); i++) {
    cout << hoge[i] << endl;
  }
  for (int i = 0; i < hoge.size(); i++) {
    if (i == 0) {
      sum = (hoge[i] + hoge[i + 1]) / 2;
    } else if (i == 1) {
      continue;
    } else {
      sum = (sum + hoge[i]) / 2;
    }
  }
  cout << fixed << setprecision(4) << sum << endl;
}
