Optimal Representation of Large-Scale Graph Data Based on Grid Clustering and K²-Tree

Table 1

Comparison of spatial complexity when using an adjacency matrix and adjacency table for a directed graph and undirected graph.

Graph type	Directed graph	Undirected graph
Adjacency Matrix	O (n^2)	O (n(n − 1)/2)
Adjacency List	O (n + m)	O (n + m)