#include <iostream>
#include<algorithm>
#include<iomanip>
using namespace std;
int n;
double sum;
struct time
{
    int t,i;
}a[1002];
bool cmp(time x,time y)
{
    return x.t<y.t;
}
int main()
{
    cin>>n;
    for(int j=1;j<=n;j++){
        cin>>a[j].t;
        a[j].i=j;
    }
    sort(a+1,a+n+1,cmp);
    for(int j=1;j<=n;j++){
        cout<<a[j].i<<" ";
        sum+=a[j].t*(n-j);
    }
    cout<<endl<<fixed<<setprecision(2)<<sum/n;
    return 0;
}