### BFS in Topological Sorting(Kahn)

Topological sorting is about DAG(Directed Acyclic Graph). The main idea of Kahn algorithm is to: Repeatedly find the start node(no income path, in-degree is 0) and print it. To find the start node, there are many ways. Given in-degree is the most convenient one. While sometimes we might need a map(hash map) to map the … More BFS in Topological Sorting(Kahn)