#include<iostream>
using namespace std ;
class ststic{
    private:
    double mean;
    
    public:
    statices(int arr[],int n){
        {
            double sum=0;
            for(int i=0;i<n;i++){
                sum+=arr[i];
            }
            mean=sum/n;
        }
    }
    statices(const statices&obj){
        mean=obj.mean;
    }
};
int main(){
    int n;
    cin>>n;
    if(n<0){
        cout<<"Invalid input";
        return 0;
    }
    int arr[100];
    for(int i=0;i<n;i++){
        cin>>arr[i];
    };
    statices s1(arr,n);
    statices s2=s1;
    cout<<s2.getMean();
    return 0;
}