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

int main()
{
	int N;
	int n;
	int *A;

	cin >> N;
	A = new int[N];
	n = N / 2;

	for (int i = 0; i < N; i++)
	{
		cin >> A[i];
	}

	sort(A, A + N);

	if (N % 2 == 0)
	{
		cout << (A[n - 1] + A[n]) / 2.0 << endl;
	}

	else
	{
		cout << A[n]<< endl;
	}

	delete[] A;
}