#include<stdio.h>
int main()
{
    int n;
    scanf("%d",&n);
    if(n<=0)
    {
        printf("No readings provided");
        return 0;
    }
    else
    {
        int a;
        float sum=0.0;
        for(int i=0;i<n;i++)
        {
            scanf("%d",&a);
            sum+=a;
        }
        float average=sum/n;
        printf("%.2f,average");
    }
        return 0;
    }