#include <iostream>
#include <memory>

class Bin_tree{
public:
	Bin_tree(const int &v) :left{ nullptr }, right{ nullptr }, factor_size{ 1 }, val{ v } {};
	void insert(const int &v) {
		++factor_size;
		if (v > val) {
			if (right) {
				right->insert(v);
			}
			else {
				right = std::make_shared<Bin_tree>(Bin_tree(v));
			}
		}
		else {
			if (left) {
				left->insert(v);
			}
			else {
				left = std::make_shared<Bin_tree>(Bin_tree(v));
			}
		}
	}
	double median() const {
		if ((factor_size & 1) == 0) {
			return (get_nth_val(factor_size >> 1) + get_nth_val((factor_size >> 1) + 1)) / 2.0;
		}
		else {
			return get_nth_val((factor_size >> 1) + 1);
		}
	}
private:
	std::shared_ptr<Bin_tree> left, right;
	int factor_size, val;
	int get_nth_val(const int &n) const {
		int l = (left) ? left->factor_size : 0;
		if (n == l + 1) {
			return val;
		}
		else if (n <= l) {
			return left->get_nth_val(n);
		}
		else {
			return right->get_nth_val(n - l - 1);
		}
	}
};
int main() {
	int n, a;
	std::cin >> n >> a;
	Bin_tree root(a);
	for (; n > 1; --n) {
		int an;
		std::cin >> an;
		root.insert(an);
	}
	std::cout << root.median() << std::endl;
	return 0;
}