Lower space bounds for accepting shuffle languages
نویسنده
چکیده
In [6] it was shown that shuffle languages are contained in one-way-NSPACE(log n) and in P. In this paper we show that nondeterministic one-way logarithmic space is in some sense the lower bound for accepting shuffle languages. Namely, we show that there exists a shuffle language which is not accepted by any deterministic one-way Turing machine with space bounded by a sublinear function, and that there exists a shuffle language which is not accepted with less than logarithmic space even if we allow two-way nondeterministic Turing machines. AMS Subject Classification. 68Q15, 68Q45.
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عنوان ژورنال:
- ITA
دوره 33 شماره
صفحات -
تاریخ انتشار 1999