By Keith Paton
Communications of the ACM,
July 1971,
Vol. 14 No. 7, Pages 468-475
10.1145/362619.362628
Comments
An efficient method is presented for finding blocks and cutnodes of an arbitrary undirected graph. The graph may be represented either (i) as an ordered list of edges or (ii) as a packed adjacency matrix. If w denotes the word length of the machine employed, the storage (in machine words) required for a graph with n nodes and m edges increases essentially as 2(m + n) in case (i), or n2/w in case (ii). A spanning tree with labeled edges is grown, two edges finally bearing different labels if and only if they belong to different blocks. For both representations the time required to analyze a graph on n nodes increases as n&ggr; where &ggr; depends on the type of graph, 1 ≤ &ggr; ≤ 2, and both bounds are attained. Values of &ggr; are derived for each of several suitable families of test graphs, generated by an extension of the web grammar approach. The algorithm is compared in detail with that proposed by Read for which 1 ≤ &ggr; ≤ 3.
The full text of this article is premium content
No entries found
Log in to Read the Full Article
Need Access?
Please select one of the options below for access to premium content and features.
Create a Web Account
If you are already an ACM member, Communications subscriber, or Digital Library subscriber, please set up a web account to access premium content on this site.
Join the ACM
Become a member to take full advantage of ACM's outstanding computing information resources, networking opportunities, and other benefits.
Subscribe to Communications of the ACM Magazine
Get full access to 50+ years of CACM content and receive the print version of the magazine monthly.
Purchase the Article
Non-members can purchase this article or a copy of the magazine in which it appears.