#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int a[n];
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  sort(a, a + n);
  for (int j = 1; j < n; j++) {
    a[j] = (a[j] + a[j - 1]) / 2;
  }
  cout << a[n - 1] << endl;
  return 0;
}
