Brute Force Determinization of NFAs by Means of State Covers

Finite automata determinization is a critical operation for numerous practical applications such as regular expression search. Algorithms have to deal with the possible blow up of determinization. There exist solutions to control the space and time complexity like the so called “on the fly” determinization. Another solution consists in performing brute force determinization, which is robust and technically fast, although a priori its space complexity constitutes a weakness. However, one can reduce this complexity by perfoming a partial brute force determinization. This paper provides optimizations that consist in detecting classes of unreachable states and transitions of the subset automaton, which leads in average to an exponential reduction of the complexity of brute force and partial brute force determinization.

• Type: Conference
• Year: 2004
• Where: WIA
• Authors: Jean-Marc Champarnaud, Fabien Coulon, Thomas Paranthoën
• Keywords: Artificial Intelligence, Brute Force Determinization, Partial Brute Force, Regular Expression Search, WIA 2004