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

int main()
{
int n;
int a[1001];

cin >> n;
for(int i=0; i<n; i++) cin >> a[i];

sort(a, a+n);

if(n%2) cout << a[n/2] << endl;
else cout  << (a[n/2] + a[n/2 - 1] ) * 0.5 << endl;

return 0;
}