#include<bits/stdc++.h>
using namespace std;
struct water{
	int time;
	int xb;
}s[1024];
bool cmp(water a,water b){
	return a.time<b.time;
}
int main(){
	int n,ans=0;
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>s[i].time;
		s[i].xb=i;
	}
	sort(s+1,s+n+1,cmp);
	for(int i=1;i<=n;i++){
		cout<<s[i].xb<<' ';
		ans+=i*s[n-i].time;
	}
	cout<<endl;
	printf("%.2lf",1.0*ans/n);
	return 0;
}