Dynamic dictionary matching with failure functions

Abstract

In the dynamic dictionary matching problem, a dictionary D contains a set of patterns that can change over time by insertion and deletion of individual patterns. The user also presents text strings and asks for all occun’ences of any patterns in the text. Amir, Farach, Galil, Giancarlo, and Park [2, 4] used an automaton based on suffix trees to solve the dynamic problem. We show how to match their time bounds for update and search using a failure function framework, similar to that used by Aho and Corasick to solve the static dictionary matching problem. We then show that our approach allows us to achieve faster search times at the expense of the update times. Finally, we show how to speed up the initial dictionary construction.