说明：  计算网络效率，输入参数，网络的邻接矩阵，输出任意节点对间的效率，及网络效率。 设计思路：floyd算法求最短路径，求倒数，求平均值
(Computing network efficiency, input parameters, the network' s adjacency matrix, any node between the output efficiency, and network efficiency. Design ideas: floyd shortest path algorithm, a reciprocal, an average)