#include <iostream>
#include <algorithm>
using namespace std;

int main(){
   int n;
   cin >> n;
   double a[n];
   for(int i = 0;i < n;i++) cin >> a[i];
   sort(a,a + n);
   if(n % 2) cout << a[n / 2 - 1] << endl;
   else cout << (a[n / 2 - 1] + a[n / 2]) / 2 << endl;
}