#include <iostream>
#include <vector>
#include <algorithm>

int main(int argc, char *argv[]) {
	int task_size = 0;
	int input = 0;
	double median = 0;
	std::vector<int> input_array;

	std::cin >> task_size;
	for (int i = 0; i < task_size; i++) {
		std::cin >> input;
		input_array.push_back(input);
	}

	std::sort(input_array.begin(), input_array.end());

	int half_size = task_size / 2;
	int middle_first = 0;
	int middle_second = 0;

	if (task_size % 2 != 0) {
		median = input_array[half_size];
	} else {
		middle_first = input_array[half_size - 1];
		middle_second = input_array[half_size];
		median = (middle_first + middle_second) / 2.0;
	} 

	std::cout << median << std::endl;
	return 0;
}