#include <bits/stdc++.h>
#include <vector>
#include <iostream>
#include <map>
#include <string>
#include <cmath>
#include <algorithm>
#include <queue>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repe(i,x,n) for(int i=x; i<(n); ++i)
using ll = long long;
using P = pair<int, int>;
#define pai 3.1415926535897932384
#define INF 100100100
#define _GLIBCXX_DEBUG
#define All(a) (a).begin(),(a).end()
#define rAll(a) (a).rbegin(),(a).rend()

int main() {
    
    int N;
    cin >> N;
    vector<double> A(N);
    rep(i,N) {
        cin >> A[i];
    }
    sort(All(A));
    if(N%2 == 0) {
        cout << (A[N/2-1]+A[(N/2)])/2 << endl;
    }
    else {
        cout << A[(N/2)] << endl;
    }

}