#include "iostream"
#include "cmath"
#include "algorithm"
#include "string"
#include "vector"
using namespace std;

vector<int> v;
int n, a;

void input(){
	for (int i = 0; i < n; i++) {
		cin >> a;
		v.push_back(a);
	}
}

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

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

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

	return 0;
}