1976/01/01 by J. R. Ullmann · 8 citations
Computer Science · Mathematics · #Parallel Computing and Optimization Techniques #Logic, programming, and type systems #Formal Methods in Verification #Subgraph isomorphism problem #Induced subgraph isomorphism problem #Graph isomorphism #Isomorphism (crystallography) #Computer science #Algorithm #Enumeration #Search tree #Graph homomorphism #Graph factorization #Asynchronous communication #Successor cardinal #Theoretical computer science #Mathematics #Combinatorics #Graph #Search algorithm #Line graph
paper · pdf · doi:10.1145/321921.321925
openalex publication_date 1976/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
Subgraph isomorphism can be determined by means of a brute-force tree-search enumeration procedure. In this paper a new algorithm is introduced that attains efficiency by inferentially eliminating successor nodes in the tree search. To assess the time actually taken by the new algorithm, subgraph isomorphism, clique detection, graph isomorphism, and directed graph isomorphism experiments have been carried out with random and with various nonrandom graphs. A parallel asynchronous logic-in-memory implementation of a vital part of the algorithm is also described, although this hardware has not actually been built. The hardware implementation would allow very rapid determination of isomorphism.