#include <iostream>
#include <algorithm>
#include <iomanip>
using namespace std;
struct ren
{
    int i, time;
} a[1001];
bool cmp(ren a, ren b)
{
    return a.time < b.time;
}
int n, sum = 0;
int main()
{
    cin >> n;
    for (int i = 1; i <= n; i++)
        cin >> a[i].time, a[i].i = i;
    sort(a + 1, a + n + 1, cmp);
    for (int i = 1; i <= n; i++)
        cout << a[i].i << ' ';
    cout << endl;
    for (int i = 1; i <= n; i++)
        sum += (n - i) * a[i].time;
    cout << fixed << setprecision(2) << sum * 1.0 / n;
    return 0;
}