#include <iostream>
#include <vector>
#include <algorithm>
//#include <string>
//#include <iomanip>

using namespace std;

int main()
{
	int N;
	cin >> N;
	vector<int> A(N);
	for (int i = 0; i < N; i++)
		cin >> A.at(i);

	sort(A.begin(), A.end());

	if (N % 2 == 0)
	{
		cout << ((A.at(N / 2) + A.at(N / 2 - 1)) / 2.0) << endl;
	}
	else
	{
		cout << A.at((N - 1) / 2) << endl;
	}

	return 0;
}