#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
struct water{
    int num,time;
} p[1010];
bool cmp(water a,water b)
{
    if(a.time != b.time)
    return a.time < b.time;
    return a.num < b.num;
}
int n , sum = 0;
int main()
{
    cin >> n;
    for(int i = 1;i <= n;i++)
    {
        //cin >> p[i].time;
        scanf("%d",&p[i].time);
        p[i].num = i;
    }
    sort(p + 1,p + n + 1,cmp);
    for(int i = 1;i <= n;i++)
    {
        //cout << p[i].num << " ";
        printf("%d ",p[i].num);
        sum += (n - i)* p[i].time;
    }
    //cout << endl;
    printf("\n%.2lf\n",1.0 * sum / n);
    return 0;
}