Detecting useless transitions in pushdown automata
نویسندگان
چکیده
منابع مشابه
Detecting Useless Transitions in Pushdown Automata
Pushdown automata may contain transitions that are never used in any accepting run of the automaton. We present an algorithm for detecting such useless transitions. A finite automaton that captures the possible stack content during runs of the pushdown automaton, is first constructed in a forward procedure to determine which transitions are reachable, and then employed in a backward procedure t...
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Context-free languages can be expressed by means of pushdown automata. Pushdown automata may contain transitions that are never used in any accepting run. Such transitions do not affect the languages the automata define, but they increase their memory requirements as well as their running time and thus it is desirable to remove them. The aim of this paper is to examine the performance of two di...
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The critical pair/completion (CPC) technique was initiated in the mid sixties in three separated areas: theorem proving [12], polynomial ideal theory [3] and term rewriting [9]. For theoretical and practical reasons, improvements of CPC algorithms were developed in two main directions. The rst one concerns strategies for selecting critical pairs. In [10], strategies consisting in adding the new...
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This contribution presents reducing variant of the deep pushdown automata. Deep pushdown automata is a new generalization of the classical pushdown automata. Basic idea of the modification consists of allowing these automata to access more deeper parts of pushdown and reducing strings to non-input symbols in the pushdown. It works similarly to bottom-up analysis simulation of context-free gramm...
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ژورنال
عنوان ژورنال: Information and Computation
سال: 2020
ISSN: 0890-5401
DOI: 10.1016/j.ic.2020.104612