02 P1223 排队接水

题目：

代码：

#include<iostream>
#include<algorithm>
using namespace std;
#define M 100005struct person
{double time;int num;int wait;
}a[M];bool cmp(person p1,person p2)
{return p1.time<p2.time;
}int main()
{int n;cin>>n;for(int i=1;i<=n;i++){cin>>a[i].time;a[i].num=i;}sort(a+1,a+n+1,cmp);for(int i=1;i<=n;i++){cout<<a[i].num<<" ";for(int j=1;j<=i-1;j++){a[i].wait+=a[j].time;}}double sum=0;for(int i=1;i<=n;i++){sum+=a[i].wait;}double averge=sum/n;printf("%.2lf",averge);}