2 research outputs found
Regular Expression Search on Compressed Text
We present an algorithm for searching regular expression matches in
compressed text. The algorithm reports the number of matching lines in the
uncompressed text in time linear in the size of its compressed version. We
define efficient data structures that yield nearly optimal complexity bounds
and provide a sequential implementation --zearch-- that requires up to 25% less
time than the state of the art.Comment: 10 pages, published in Data Compression Conference (DCC'19
On the Use of Quasiorders in Formal Language Theory
In this thesis we use quasiorders on words to offer a new perspective on two
well-studied problems from Formal Language Theory: deciding language inclusion
and manipulating the finite automata representations of regular languages.
First, we present a generic quasiorder-based framework that, when instantiated
with different quasiorders, yields different algorithms (some of them new) for
deciding language inclusion. We then instantiate this framework to devise an
efficient algorithm for searching with regular expressions on
grammar-compressed text. Finally, we define a framework of quasiorder-based
automata constructions to offer a new perspective on residual automata.Comment: PhD thesi