WHEN CHURCH-ROSSER BECOMES CONTEXT FREE
2007 ◽
Vol 18
(06)
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pp. 1293-1302
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Keyword(s):
We investigate the intersection of Church-Rosser languages and (strongly) context-free languages. The intersection is still a proper superset of the deterministic context-free languages as well as of their reversals, while its membership problem is solvable in linear time. For the problem whether a given Church-Rosser or context-free language belongs to the intersection we show completeness for the second level of the arithmetic hierarchy. The equivalence of Church-Rosser and context-free languages is Π1-complete. It is proved that all considered intersections are pairwise incomparable. Finally, closure properties under several operations are investigated.
2005 ◽
Vol 16
(03)
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pp. 423-440
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Keyword(s):
2009 ◽
Vol 53
(6)
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pp. 547-561
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Keyword(s):
1970 ◽
Vol 16
(2)
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pp. 201-202
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2014 ◽
Vol 577
◽
pp. 917-920
2011 ◽
Vol 14
◽
pp. 34-71
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2013 ◽
Vol 24
(07)
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pp. 1067-1082
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Keyword(s):