#include<iostream>
#include<algorithm>

using namespace std;

typedef long long LL;
LL T,sum;
int n;
const int N = 1e4;

LL a[N];

struct person
{
    int x;
    int t;
}people[N];

bool cmp(person x,person y)
{
    return x.t<y.t;
}


int main()
{
    cin>>n;
    for(int i=0;i<n;i++)
    {
        cin>>people[i].t;
        people[i].x=i;
    }
    sort(people,people+n,cmp);
    for(int i=1;i<n;i++)
    {
        a[i]+=a[i-1]+people[i-1].t;
    }
    for(int i=0;i<n;i++)
    sum+=a[i];
    double aver=sum/n;
    for(int i=0;i<n;i++)
    {
        printf("%d ",people[i].x+1);
    }
    cout<<endl;
    printf("%.2lf",aver);
    return 0;
}