Perfect Hashing with Pseudo-minimal Bottom-up Deterministic Tree Automata
نویسندگان
چکیده
We describe a technique that maps unranked trees to their hash codes using a bottom-up deterministic tree automaton (DTA). In contrast to techniques implemented with minimal tree automata, our procedure builds a pseudo-minimal DTA. Pseudo-minimal automata are larger than the minimal ones but in turn the mapping can be arbitrary, so it can be determined prior to the automaton construction. We also provide procedures to build incrementally the pseudo-minimal DTA and the associated hash codes.
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