用C写的源程序功能分别是1.用DFS算法判断有向图中是否有环2.从文件中读图，用邻接链表保存信息，寻找两个结点vi,vj间的最短路径-written in C source is a function respectively. DFS algorithm used to determine whether there are plans Central 2. Interpret drawings from the file, use the adjacent Chain preservation of information to find two nodes vi, vj the shortest path