Finite automata with generalized acceptance criteria

Abstract

We examine the power of nondeterministic finite automata with acceptance of an input word defined by a so called leaf language, i. e., a condition on the sequence of leaves in the automaton's computa- Tion tree. We study leaf languages either taken from one of the classes of the Chomsky hierarchy, or taken from a time- or space-bounded com- plexity class. We contrast the obtained results with those known for leaf languages for Turing machines and Boolean circuits. © Springer-Verlag Berlin Heidelberg 1999.