一个连通图可以有多个生成树，实际应用中希望所选的生成树的权值总和最小，这就是最小生成树的问题。代码实现用Kruskal算法实现求解最小生成树。-A connected graph can have multiple spanning tree, hope in the actual application of the selected total weight minimum spanning tree, this is the minimum spanning tree problem. C