Luogu P3958 奶酪

Posted 2021-03-10 kingbenqi

#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
int n;
double h,r;
struct Cheese{
  double x,y,z;
    //重载运算符
  bool operator<(const Cheese &cpr) const{
    return z<cpr.z;
  }
}C[1010];
bool flag=0;
bool vis[1010];
void dfs(int now){
  //cout<<"now="<<now<<" C.x="<<C[now].z<<endl;
  if(h-C[now].z<=r){
    flag=1;
    return;
  }
  vis[now]=1;
  for(int i=1;i<=n;i++){
    if(!vis[i]){
      double dist=sqrt((C[now].x-C[i].x)*(C[now].x-C[i].x)+(C[now].y-C[i].y)*(C[now].y-C[i].y)+(C[now].z-C[i].z)*(C[now].z-C[i].z));
      if(dist<=2*r) dfs(i);
            
    }
  }
}
int main(){
  int T;
  cin>>T;
  while(T--){
    memset(vis,0,sizeof(vis));
    memset(C,0,sizeof(C));
    flag=0;
    cin>>n>>h>>r;
    for(int i=1;i<=n;i++) cin>>C[i].x>>C[i].y>>C[i].z;
    sort(C+1,C+n+1);
    for(int i=1;i<=n;i++){
      if(C[i].z-r<=0)dfs(i);
    }
    if(flag)puts("Yes");
    else puts("No");
  }
  return 0;
    
}