以偶对的形式输入一个无向简单图的边，建立该图的邻接矩阵，判断图是否连通（A）。并计算任意两个结点间的距离（B）。对不连通的图输出其各个连通支（C）。-Even on the form to input an undirected graph edge, the establishment of the adjacency matrix to determine whether the connectivity graph (A). And calculate any distance betwe