设有一个有向图存储在邻接表中。试设计一个算法，按深度优先搜索策略对其进行拓扑排序。并以右图为例检验你的算法的正确性。-There is a directed graph stored in the adjacent table. Trial design an algorithm, depth-first search strategy by the topology of its sort. And to test your example picture on the right algorithm.