Efficient String Matching: An Aid to Bibliographic Search
📜 Abstract
An algorithm is presented for locating all occurrences of any of a finite number of keywords in a string of text. The algorithm constructs a finite state pattern matching machine from the keywords and uses this machine to do the searching. The construction of the pattern matching machine is a variant of the construction of the recognizer for a regular expression. The machine is deterministic and has at most one more state than the total length of all keywords. The time to construct the machine is proportional to the total number of characters in all keywords. Once constructed, the machine can process the text in time that is linear in the number of characters plus the number of keywords matched. The algorithm is particularly applicable to the design of bibliographic search systems, and the techniques developed below can be applied in other areas of text processing and pattern recognition as well.
✨ Summary
The paper “Efficient String Matching: An Aid to Bibliographic Search”, authored by Alfred V. Aho and Margaret J. Corasick, presents a groundbreaking algorithm for string matching that constructs a finite state machine to manage pattern recognition across various keywords within a text. Published in June 1975, this work proposes a method that is efficient in terms of both construction time and operational time, suitable for bibliographic searches and other text processing applications.
The Aho-Corasick algorithm is renowned for its speed and efficiency, influencing a wide range of applications in computer science, particularly in the fields of text processing and search algorithms. Compared to other string searching algorithms like the Knuth-Morris-Pratt (KMP) and Boyer-Moore, Aho-Corasick stands out for its ability to handle multiple patterns simultaneously, which makes it exceedingly valuable in areas requiring fast and efficient pattern matching.
The influence of this algorithm extends beyond bibliographic search systems into various domains such as network security (for example, intrusion detection systems), bioinformatics for DNA sequencing, and text data mining. Its impact is documented in multiple downstream applications and scholarly articles. Some notable references include: - Yu, S., et al. (2004). “The Design and Implementation of a High-Performance Network Intrusion Detection System.” ACM Transactions on Computer Systems, which utilizes the Aho-Corasick algorithm. - Gusfield, D. (1997). “Algorithms on Strings, Trees, and Sequences: Computer Science and Computational Biology,” featuring an application of Aho-Corasick for biological sequence analysis. - Rivest, R.L. (1992). “The MD5 Message-Digest Algorithm,” where efficient pattern matching algorithms are crucial for hashing and data integrity verification processes.
Despite its actionable generality and utility, the methodological simplicity of the Aho-Corasick algorithm ensures its continued relevance and application viability in modern computational problems.