#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, v[1000], ans;
  cin >> N;
  for (int i = 0; i < N; ++i) cin >> v[i];
  sort(v, v + N);
  for (int i = 1; i < N; ++i) v[i] = (v[i - 1] + v[i]) / 2;
  cout << v[N - 1] << endl;
  return 0;
}
