#include "iostream"
#include "vector"
#include "algorithm"
using namespace std;

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