91分求调

#include <iostream>
#include <algorithm>
#include <cmath>
#include <iomanip>
using namespace std;
int a[2000001], b[2000001], c[2000001];
int main()
{
	int n;
	double s = 0;
	cin >> n;
	for (int i = 1; i <= n; i++)
	{
		cin >> a[i];
		c[i] = a[i];
		b[a[i]] = i;

	}
	sort(a + 1, a + n + 1);
	sort(c + 1, c + n + 1);
	for (int i = 1; i <= n; i++)
	{
		a[i] *= (n - i);
		s += a[i];
	}
	for (int i = 1; i <= n; i++)
	{

		cout << b[c[i]] ;
        if(i!=n)cout<<" ";

	}
	cout << endl;
	s /= n;
	cout << fixed << setprecision(2) << s << endl;
	return 0;
}