```cpp
for (ll i=n;i>=1;i--)
{
while(head<=tail&&a[q[head]].x-a[i].x>d)head++;
if (a[q[head]].h>=a[i].h*2)vis[i]++;
while(head<=tail&&a[i].h>=a[q[tail]].h)tail--;
q[++tail]=i;
}
```
`while(head<=tail&&a[q[head]].x-a[i].x>d)head++;`要打成`while(head<=tail&&a[i].x-a[q[head]].x>d)head++;`
by Sity_Hugh @ 2022-08-17 12:22:23
@[Sity_Hugh](/user/457666) 草我也忘了要把式子倒过来
by tllwtg @ 2023-01-09 21:55:00