Regulated Grammars with Leftmost Derivation
نویسنده
چکیده
In this paper, we investigate various concepts of leftmost derivation in grammars controlled by bicoloured digraphs, especially regarding their descriptive capacity. This approach allows us to unify the presentation of known results regarding especially programmed grammars and matrix grammars, and to obtain new results concerning grammars with regular control, and periodically time-variant grammars. Moreover , we get new results on leftmost derivations in conditional grammars.
منابع مشابه
On the Complexity of Szilard Languages of Regulated Grammars
We investigate computational resources used by alternating Turing machines (ATMs) to accept Szilard languages (SZLs) of regulated rewriting grammars. The main goal is to relate these languages to lowlevel complexity classes such asNC1 andNC2. We focus on the derivation process in random context grammars (RCGs) with context-free rules. We prove that unrestricted SZLs and leftmost-1 SZLs of RCGs ...
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