Language Theory and Infinite Graphs
نویسنده
چکیده
Automata and language theory study finitely presented mechanisms for generating languages. A language is a family of words. A slight shift in focus is very revealing. Instead of grammars and automata as language generators, one views them as propagators of possibly infinite labelled transition graphs. This is our starting point for pushdown automata. The main goal is to report on a proof of decidability of language equivalence for deterministic pushdown automata that uses both graph theoretic and combinatorial arguments.
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