#include <bits/stdc++.h>
using namespace std;
typedef unsigned long long ul;
typedef signed long long ll;
ul over = 1000000007;

int main(void)
{
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed;
  int n;
  cin >> n;
  int a[n];
  for (int i = 0; i < n; ++i) cin >> a[i];
  sort(a, a+n);
  if (n%2==1) cout << a[n/2] << endl;
  else cout << (a[n/2-1] + a[n/2])/2.0 << endl;
  return 0;
}