#include <bits/stdc++.h>
using namespace std;

int n;
double a[1000];

int main()
{
	cin >> n;

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

	sort(a, a + n);

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