The computational complexity of the improved algorithm approaches polynomial complexity, much less than 2 N ( N is the vertex number of a graph).
后者的计算时间复杂性远远低于2 N（N为图的顶点数） ，已接近于多项式时间复杂性。
2
Let G be a graph and let V(G) be the vertex set of G. Define the neighborhood complex N(G) as the simplicial complex whose simplices are those subsets of V(G) which have a common neighbor.
一个图G的邻域复形是以G的顶点为顶点，以G的具有公共邻接顶点的顶点子集为单形的抽象复形。
3
The generative rule of arbitrary N-rank K-regular simple graph is studied, and the method of recursively generating arbitrary N-rank K-regular graph from the simple complete graph is put forward.