#include<bits/stdc++.h>
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;
}
long long 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;
}