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

int main() {
	int n;
	cin >> n;

	float A[1000];
	for (int i = 0; i < n; i++)
	{
		cin >> A[i];
	}
	sort(A, A + n);

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

	return 0;
}