```cpp
#include <iostream>
#include <cmath>
#include <cstring>
using namespace std;
int t, n, h, r, xyz[1005][3], down[1005], cnt, up[1005], arr[1005][1005], mark[1005];
int func(int now) {
if (up[now] == 1) {
return 1;
}
for (int i = 1; i <= n; i++) {
if (arr[now][i] == 1 && mark[i] == 0) {
mark[i] = 1;
if (func(i) == 1) {
return 1;
}
}
}
return 0;
}
int main() {
cin >> t;
while (t--) {
cnt = 0;
memset(up, 0, sizeof(up));
memset(arr, 0 ,sizeof(arr));
memset(mark, 0, sizeof(mark));
cin >> n >> h >> r;
for (int i = 1; i <= n; i++) {
cin >> xyz[i][0] >> xyz[i][1] >> xyz[i][2];
if (xyz[i][2] <= r) {
down[cnt] = i;
cnt++;
}
if (xyz[i][2] + r >= h) {
up[i] = 1;
}
for (int j = 1; j < i; j++) {
long long t1 = xyz[i][0] - xyz[j][0];
long long t2 = xyz[i][1] - xyz[j][1];
long long t3 = xyz[i][2] - xyz[j][2];
double dis = sqrt(t1 * t1 + t2 * t2 + t3 * t3);
if (dis <= 2 * r){
arr[i][j] = arr[j][i] = 1;
}
}
}
int flag = 0;
for (int i = 0; i < cnt; i++) {
if (mark[down[i]] == 1) {
continue;
} else {
mark[down[i]] = 1;
}
if (func(down[i]) == 1) {
flag = 1;
break;
}
}
if (flag == 0) {
cout << "No" << endl;
} else {
cout << "Yes" << endl;
}
}
return 0;
}
```
by 今年我15 @ 2021-07-15 20:07:13
@[今年我15](/user/540244) 谢谢！
by GUN_ @ 2021-07-23 20:15:16