#include <bits/stdc++.h>

using namespace std;

int main() {
	int N; cin >> N;
	vector<int> v(N);
	for (int i = 0; i < N; ++i) {
		cin >> v[i];
	}
	sort( v.begin(), v.end() );
	if (v.size() % 2) {
		cout << v[v.size()/2] << endl;
	}
	else {
		int pos = v.size()/2-1;
		cout << (v[pos]+v[pos+1])/2.0 << endl;
	}
}