A lower bound on the size of ɛ-free NFA corresponding to a regular expression

Authors:
Yuri Lifshits
Affiliations:
St. Petersburg State University, Faculty of Mathematics and Mecanics, Department of Algebra, Bibliotechnaya pl. 2, Stary Peterhof 198504, Russia
Venue:
Information Processing Letters
Year:
2003

Citing 1
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Abstract

Hromkovic et al. showed how to transform a regular expression of size n into an ε-free nondeterministic finite automaton (which defines the same language as the expression) with O(n) states and O(n log2 (n)) transitions. They also established a lower bound Ω (n log(n)) on the number of transitions. We improve the lower bound to Ω(nlog2n/loglogn).