#include <iostream>
#include <algorithm>
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);
  if(n%2==0) cout << (double)(a[n/2-1]+a[n/2])/2 <<endl;
  else cout << a[n/2] << endl;
  return 0;
}