Succinctness of regular expressions with interleaving, intersection and counting
Theoretical Computer Science
The complexity of regular(-like) expressions
DLT'10 Proceedings of the 14th international conference on Developments in language theory
The tractability frontier for NFA minimization
Journal of Computer and System Sciences
State complexity of the concatenation of regular tree languages
Theoretical Computer Science
State complexity of kleene-star operations on trees
WTCS'12 Proceedings of the 2012 international conference on Theoretical Computer Science: computation, physics and beyond
State complexity of projection and quotient on unranked trees
DCFS'12 Proceedings of the 14th international conference on Descriptional Complexity of Formal Systems
Descriptional complexity of deterministic regular expressions
MFCS'12 Proceedings of the 37th international conference on Mathematical Foundations of Computer Science
Unshuffling a square is NP-hard
Journal of Computer and System Sciences
Hi-index | 0.01 |
We improve on some recent results on lower bounds for conversion problems for regular expressions. In particular we consider the conversion of planar deterministic finite automata to regular expressions, study the effect of the complementation operation on the descriptional complexity of regular expressions, and the conversion of regular expressions extended by adding intersection or interleaving to ordinary regular expressions. Almost all obtained lower bounds are optimal, and the presented examples are over a binary alphabet, which is best possible.