#include <iostream>
using namespace std;
class statistics{
    double mean;
    
public:
      statistics(int arr[],int n){
          double sum=0;
          for (int i=0;){
              sum+=arr[i];
          }
          mean=sum/n;
      }
      statistics(const statistics& obj){
          mean= obj.mean;
      }
      void display(){
          cout<<mean;
      }
      
};
int main(){
    int n;
    cin>>n;
    if(n<0){
        cout<<"Invalid input";
        return 0;
    }
    int arr[n];
    for (int i=0; i<n,i++){
        cin>>arr[i];
    }
    statistics s1(arr,n);
    statistics s2=s1;
    s2.display();
    return 0;
    
}