#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

int main(){
	cin.tie(nullptr);
	ios_base::sync_with_stdio(false);
	
	int n;
	cin >> n;
	vector<double> a(n);
	rep(i,n) cin >> a[i];
	sort(a.begin(),a.end());
	if(n%2 == 1) cout << a[n/2] << endl;
	else cout << (a[n/2]+a[n/2-1])/2 << endl;
	return 0;
}