#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <utility>

using namespace std;

int main(void){

    int n;
    cin >> n;
    vector<int> a(n);
    for(int i = 0; i < n; i++) cin >> a[i];
    sort(a.begin(), a.end());
    if(n % 2){
        cout << a[n/2] << endl;
    }else{
        cout << (double)(a[n/2 - 1] + a[n/2]) / 2 << endl;
    }

    return 0;
}