#include<iostream>
#include<stdio.h>
#include<algorithm>
using namespace std;
struct people {
	int xvhao,t ;//m 序号，
} a[1010];
bool cmp(people x, people y) {
	return x.t < y.t;
}
int main() {
	int n;
	scanf("%d", &n);
	for (int i = 0; i < n; i++)
	{
		a[i].xvhao = i+1;
		scanf("%d", &(a[i].t));
	}
	sort(a, a + n, cmp);
	int sum = 0;
	for (int i = 0; i < n; i++)
	{
		printf("%d ", a[i].xvhao);
		sum += a[i].t * (n - i-1);
		//lif += a[i].t;
	}
	printf("\n");
	printf("%.2lf", sum*1.0 / (1.0 * n));
}