P3958 奶酪

一个爆搜就A了

CODE:

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#define ll long long
using namespace std;
double dis(ll a1, ll a2, ll b1, ll b2, ll c1, ll c2){
    return sqrt((a1-a2)*(a1-a2)+(b1-b2)*(b1-b2)+(c1-c2)*(c1-c2));
}
int T, n, flag, vis[1001];
ll h, r;
struct node{
    ll x, y, z;
}e[1001];
void dfs(int x){
    if(e[x].z+r>=h) flag=1;
    if(flag)return;
    vis[x]=1;
    for(int i=1; i<=n; i++){
        if(i==x)continue;
        if(!vis[i]&&dis(e[x].x, e[i].x, e[x].y, e[i].y, e[x].z, e[i].z)<=2*r)dfs(i);
    }
}
int main(){
    scanf("%d", &T);
    while(T--){
        flag=0;
        memset(vis, 0, sizeof(vis));
        scanf("%d%lld%lld", &n, &h, &r);
        for(int i=1; i<=n; i++)
            scanf("%lld%lld%lld", &e[i].x, &e[i].y, &e[i].z);
        for(int i=1; i<=n; i++){
            if(e[i].z-r<=0) dfs(i);
            if(flag){
                printf("Yes\n");
                break;
            }
        }
        if(!flag)printf("No\n");
    }
    return 0;
}