#include <bits/stdc++.h>
int main(int argc, char** argv) {
  int N;
  std::cin >> N;
  std::vector<double> values;
  for (int i = 0; i < N; ++i) {
    double V;
    std::cin >> V;
    values.push_back(V);
  }
  std::sort(std::begin(values), std::end(values));
  double x = values[0];
  for (int i = 1; i < N; ++i) {
    double y = values[i];
    x = (x + y) * 0.5;
  }
  std::cout << static_cast<int>(x) << std::endl;
  return 0;
}
