#include <bits/stdc++.h>
int main(void) {
  int N;
  double res = 0;
  scanf("%d", &N);
  std::vector<int> v;
  v.reserve(N);
  for (int n = 0; n < N; ++n) {
    int i;
    scanf("%d", &i);
    v.push_back(i);
  }
  printf("%lu\n", v.size());
  std::sort(v.begin(), v.end());
  res = v[0];
  for (int n = 1; n < N; n++) {
    res = (res + v[n]) / 2.0;
  }
  printf("%.10f\n", res);
  return 0;
}
