假设图中数据元素类型是字符型，请采用邻接矩阵或邻接表实现图的以下基本操作： （1）构造图（包括有向图、有向网、无向图、无向网）； （2）根据深度优先遍历图。

Assuming that the data element type in the graph is a character type, use the adjacency matrix or adjacency table to implement the following basic operations of the graph: (1) Construction graph (including directed graph, directed mesh, undirected graph, undirected mesh); ) traverse the graph according to depth first.