题解

#include <bits/stdc++.h>
using namespace std;
struct Node{long long x,y,z;};
int main()
{
    int t=0;
    cin>>t;
    for(int w=0;w<t;w++)
    {
        long long x[1009]={0};
        long long y[1009]={0};
        long long z[1009]={0};
        int vst[1009]={0};
        int tru=0;
        int n=0,h=0,r=0;
        cin>>n>>h>>r;
        for(int i =1;i<=n;i++)
        {
            cin>>x[i]>>y[i]>>z[i];
        }
        queue<Node> q;
        for(int i =1;i<=n;i++)
        {
            if(z[i]<=r)
            {
              vst[i]=1;
                q.push((Node){x[i],y[i],z[i]});
                //cout<<h-z[i]<<" "<<r<<endl;
                if(h-z[i]<=r)
                {
                        tru=1;
                        break;
                }
            }
        }
        while(!q.empty()&&tru==0)
        {
            Node now=q.front();
            q.pop();
            for(int i =1;i<=n;i++)
            {
                if(sqrt((x[i]-now.x)*(x[i]-now.x)+(y[i]-now.y)*(y[i]-now.y)+(z[i]-now.z)*(z[i]-now.z))<=r*2&&sqrt((x[i]-now.x)*(x[i]-now.x)+(y[i]-now.y)*(y[i]-now.y)+(z[i]-now.z)*(z[i]-now.z))!=0&&vst[i]==0)
                {
                    q.push((Node){x[i],y[i],z[i]});
                    vst[i]=1;
                    //cout<<h-now.z<<" "<<r<<endl;
                    if(h-now.z<=r)
                    {
                        tru=1;
                        break;
                    }
                }
            }
        }
        for(int i =1;i<=n;i++)
        {
          if(h-z[i]<=r&&vst[i]==1)
          {
            tru=1;
            break;
          }
        }
        if(tru==0){
            cout<<"No"<<endl;
        }
        else
        {
        	cout<<"Yes"<<endl;
    	}
    }
    return 0;
}