Design and analysis of computer algorithms
In particular, design and analysis of algorithms for finding maximum and maximal cliques
and their applications (to bioinformatics, image processing, analysis of social networks, and so on.)
Automata and formal language theory
In particular, design and analysis of algorithms for deciding equivalence or inclusion problems
of deterministic pushdown automata and deterministic pushdown transducers.
Algorithmic learning theory
In particular, learning by representative set of strings and that based on the above described results.