题目链接

#include <iostream>
#include <cstring>
#include <algorithm>
#include <queue>
using namespace std;
const int N = 200010;
#define int long long
int n;
struct node
{
    int z,x,y;
    bool operator < (const node & W)const
    {
        return z<W.z;
    }
}a[N];
bool cmp(node a,node b)
{
    return a.y<b.y;
}
signed main()
{
    priority_queue<node>heap;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        int z,x,y;cin>>z>>x>>y;
        a[i]={z,x,y};
    }
    sort(a+1,a+n+1,cmp);
    int tmp=0;
    double res=0.0;
    for(int i=1;i<=n;i++)
    {
        heap.push(a[i]);
        tmp+=a[i].x;
        if(tmp>a[i].y)
        {
            int num=tmp-a[i].y;
            tmp=a[i].y;
            while(heap.size())
            {
                 if(num==0)break;
                auto t=heap.top();heap.pop();
                if(num>t.x)
                {
                    res+=(double)t.x*1.0/t.z;
                    num-=t.x;
                }
                else
                {
                    res+=(double)num*1.0/t.z;
                    t.x-=num;
                    heap.push(t);
                    num=0;
                }
            }
        }
    }
    printf("%.1lf\n",res);
}