#include <iostream>
#include <string>
#include <vector>
#include <cmath>
#include <fstream>
#include <set>
#include <utility>
#include <algorithm>

#define rep(i,p,n) for(int i=p;i<n;i++)
#define lli long long int
#define vi vector<int> 

using namespace std;

int max(int x, int y) {
	int a;
	(x > y) ? a = x : a = y;
	return a;
}

int min(int x, int y) {
	int a;
	(x < y) ? a = x : a = y;
	return a;
}

int main() {
	int n;
	cin >> n;
	vi v(n);
	rep(i, 0, n) cin >> v[i];

	sort(v.begin(), v.end());

	if (n % 2 == 1) {
		cout << v[n / 2] << endl;
	}
	else {
		cout << (double)(v[n / 2] + v[n / 2 - 1]) / 2 << endl;
	}

	return 0;
}