Alternating and empty alternating auxiliary stack automata
نویسندگان
چکیده
منابع مشابه
Alternating and Empty Alternating Auxiliary Stack Automata
We consider variants of alternating auxiliary stack automata and characterize their computational power when the number of alternations is bounded by a constant or unlimited. In this way we get new characterizations of NP, the polynomial hierarchy, PSpace, and bounded query classes like co-DP=NL〈NP[1]〉 and 2P=P , in a uniform framework. c © 2002 Elsevier Science B.V. All rights reserved.
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2003
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(02)00326-2