可以用结构体排序+贪心

//A21499.排队接水
#include<bits/stdc++.h>
using namespace std;
struct node{
	int x,id;
}a[1000+10];
bool cmp(node x, node y){
	return x.x < y.x;
}
int main(){
	int n;
	double sum = 0,s = 0;
	cin >> n;
	for(int i=1;i<=n;i++){
		cin >> a[i].x;
		a[i].id = i;
	}
	sort(a+1,a+n+1,cmp);
	for(int i=1;i<=n-1;i++){
		s += a[i].x;
		sum += s;
	}
	for(int i=1;i<=n;i++){
		cout << a[i].id << " ";
	}
    cout << endl;
    double avg = sum*1.0/n;
	printf("%.2f",avg);
	return 0;
}