Alternating Function Classes Within P
نویسنده
چکیده
We de ne the notion of adding \small amounts" of nondeterminism to a deterministic function class, and give a machine model; the result is a functional AC closure of the deterministic class. We characterize, by the \safe parameters" technique, the classes of functions computable in linear and in quasilinear time on a multi-tape Turing machine. We then combine these two results by extending the \safe parameters" characterizations to the functions computable in (quasi)linear time with small amounts of nondeterminism, and discuss implications for both sequential and parallel complexity. Computer Science Dept, University of Manitoba. This work was sponsored in part by NSERC operating grant OGP0121527.
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