#include<bits/stdc++.h>
using namespace std;
const int N = 1005;
struct Data{
	int a,b;
}a[N];
bool cmp(Data x,Data y){
	return x.a < y.a;
}
int n;
int main(){
	double flag = 0;
	scanf("%d",&n);
	for (int i = 1;i <= n;++i){
		scanf("%d",&a[i].a);
		a[i].b = i;
		flag += a[i].a;
	}
	sort(a+1,a+n+1,cmp);
	for (int i = 1;i <= n;++i)printf("%d ",a[i].b);
	printf("\n%.2lf",flag / n);
	return 0;
}