#include<iostream>
#include<vector>
#include<algorithm>

int main(){
    int n;
    std::cin>>n;
    std::vector<int> a(n);
    for (int& element : a) {
        std::cin>>element;
    }
    std::sort(a.begin(),a.end());
    if(n%2==0){
       std::cout<<(a[n/2]+a[n/2-1])/2.0;
    }else{
        std::cout<<a[n/2];
    }
}