#include<iostream>
#include<algorithm>
using namespace std;
int main() {
	int num;
	cin >> num;
	int*data = new int(num);
	for (int i = 0; i<num; i++) {
		cin >> data[i];
	}
	sort(data, data + num);
	if (num % 2 == 1) {
		cout << data[num / 2 ];
	}
	else {
		cout << ((double)data[num / 2] + (double)data[num / 2 - 1]) / 2;
	}
	return 0;
}