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

int main(int argc, char**argv)
{
	int n; cin >> n;
	vector<int> av;
	for (int ii=0; ii<n; ++ii) {
		int a; cin >> a;
		av.push_back(a);
	}
	sort(av.begin(), av.end());

	int rs = 0;
	int sz = av.size();
	int mid = sz/2;
	if (sz%2==0) {
		cout << ( ((float)(av[mid-1]+av[mid])) / 2 ) << endl;
	}
	else {
		cout << av[mid] << endl;
	}
	return 0;
}