#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <map>
using namespace std;
int main() {
	int n; cin >> n;
	int* num = new int[n];
	map<int, int>it;
	for (int i = 0; i < n; i++) {
		cin >> num[i];
		it[num[i]] = i;
	}
	sort(num,num + n);
	for (int i = 0; i < n; i++)
		cout << it[num[i]]+1<<' ';
		cout << '\n';
		double sum=0,sum0=0,sum1=0;
	for (int i = 0; i < n-1; i++) {
		sum += num[i] * (n - 1 - i);
	}
	sum = sum * 1.0 / n;
	printf("%.2f", sum);
}