（1）键盘输入数据，建立一个有向图的邻接表，并输出该邻接表。

（2）采用邻接表存储实现有向图的深度优先遍历。

（3）试写一算法，判断以邻接表方式存储的有向图中是否存在由顶点Vi到顶点Vj的路径（i<>j）。

（4）已有邻接表表示的有向图，请编程判断从第u顶点至第v顶点是否有简单路径，若有则印出该路径上的顶点。

（5）在主函数中设计一个简单的菜单，分别调试上述算法。

-(1) keyboard input data, the establishment of a directed graph adjacency list and outputs the adjacent table.

(2) using the adjacent table storage implementation has to depth-first graph traversal.

(3) try to write an algorithm to determine the adjacent table stored there if the vertex to vertex Vj Vi path (i <> j) the presence of the figure.

There are (4) has been directed graph adjacency list representation, program judging　vertex u to vertex v and whether there is a simple path, if you print a vertex on the path.

(5) design a simple menu in the main function, namely debug the algorithm described above.