以邻接多重表为存储结构，实现连通无向图的深度优先和广度优先遍历。以用户指定的结点为起点，分别输出各种遍历下的结点访问序列和相应生成树的边集,To the adjacent multi-table for the storage structure, to achieve connectivity of undirected graph depth-first and breadth-first traversal. To user-specified node as a starting poi