#include <bits/stdc++.h>
 using namespace std;
 typedef struct Person{
 	int No;
 	int t;
 }person;
 bool cmp(person p1,person p2){
 	return p1.t < p2.t;
 }
 int main(){
 	int n; 
 	cin >> n;
 	person p[1001];
 	for(int i=1;i<=n;i++){
 		cin >> p[i].t;
 		p[i].No = i;
	 }
	 sort(p+1,p+1+n,cmp);
	 for(int i=1;i<=n;i++){
	 	cout << p[i].No << ' ';
	 }
	 cout << endl;
	 int result = 0;
	 for(int i=1;i<=n;i++){
	 	result += p[i].t * (n - i);
	 }
	 
	 cout << fixed << setprecision(2) << result * 1.0 / n<< endl;
 }