#include <iostream>
#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(){
    scanf("%d",&n);
    for (int i = 1 ; i <= n ; i ++){
        scanf("%d",&p[i].time);
        p[i].num = i ;
    }
    sort(p +1 , p + n + 1 , cmp);
    for (int i = 1 ; i <= n ; i ++){
        printf("%d ",p[i].num);
        sum += i * p[n-i].time;
    }
    printf("\n%.2lf\n",1.0 * sum / n);
    return 0;
}