# Directed Graphs 有向图

探索有向图的环 685 当然也有 207

## 拓扑排序

* 126&127
* 207&210
* 269
* 329
* 444
* 1203

## Dijkstra 算法 原则上 BFS 都可以用 Dijkstra 写 只是意义不一定大

743 最典型 [743: Network-Delay-Time](https://leetcode.com/problems/network-delay-time/) 505 [505: The-Maze-II](https://leetcode.com/problems/the-maze-ii/)\
787 743

强连通分量 <https://leetcode.com/discuss/interview-question/124827/find-minimum-number-of-people-to-reach-to-spread-a-message-across-all-people-in-twitter/124199>

最小生成树 Kruskal LC859 <https://www.acwing.com/solution/LeetCode/content/6839/>
