lp3958 NOIP2017 奶酪

简单结论+并查集+大力模拟
注意并查集不要写挂。
另：记住long double的范围小于long long

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;

#define eps 1E-9
long long n,h,r;
inline double clac(const long long &x1,const long long &y1,const long long &z1,const long long &x2,const long long &y2,const long long &z2){
    return (double)sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2)+(z1-z2)*(z1-z2));
}
long long f[1005],x[1005],y[1005],z[1005];
inline long long fa(const long long &x){
    return (f[x]==x)?(x):(f[x]=fa(f[x]));
}
inline void uni(const long long &x,const long long &y){
    (fa(x)==fa(y))?0:f[fa(x)]=fa(y);
}
bool up[1005],dn[1005];
void init(){
    scanf("%lld%lld%lld",&n,&h,&r);
    memset(up,0,sizeof(up));
    memset(dn,0,sizeof(dn));
    for(int i=1;i<=n;++i){
        f[i]=i;
    }
    long long nx,ny,nz;
    for(int i=1;i<=n;++i){
        scanf("%lld%lld%lld",&nx,&ny,&nz);
        x[i]=nx;
        y[i]=ny;
        z[i]=nz;
        if(z[i]<=r){
            dn[i]=1;
        }
        if(h-z[i]<=r){
            up[i]=1;
        }
    }
    for(int i=1;i<=n;++i){
        for(int j=1;j<=n;++j){
            if(fa(i)==fa(j)){
                continue;
            }
            if((double)(r*2)>=clac(x[i],y[i],z[i],x[j],y[j],z[j])){
                uni(i,j);
            }
        }
    }
    for(int i=1;i<=n;++i){
        if(!dn[i]){
            continue;
        }
        for(int j=1;j<=n;++j){
            if(!up[j]){
                continue;
            }
            if(fa(i)==fa(j)){
                puts("Yes");
                return;
            }
        }
    }
    puts("No");
} 
int main(){
    int T;
    scanf("%d",&T);
    while(T--){
        init();
    }
    return 0;
}