无向图功能实现，用邻接多重表存储该无向图，并使用动态存储结构。用一个单链表把所有顶点存储起来，在存储边的节点中给出该边的两个顶点的各自的下一条边的节点地址。-Undirected graph implementation of function, with the adjacent multi-table to store the graph, and using dynamic storage structures. With a single list of all vertices sto