为什么不能卡EK啊((
by DPair @ 2021-02-22 17:50:13
@[小末影龙](/user/342651) 我EK+spfa过了![](https://cdn.luogu.com.cn/upload/pic/69020.png)
<https://www.luogu.com.cn/record/45385174>
by iMya_nlgau @ 2021-02-22 18:00:06