Machine-based methods in parameterized complexity theory
نویسندگان
چکیده
We give machine characterizations of most parameterized complexity classes, in particular, of W[P], of the classes of the W-hierarchy, and of the A-hierarchy. For example, we characterize W[P] as the class of all parameterized problems decidable by a nondeterministic fixed-parameter tractable algorithm whose number of nondeterministic steps is bounded in terms of the parameter. The machine characterizations suggest the introduction of a hierarchy W between the W and the A-hierarchy. We study the basic properties of this hierarchy.
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 339 شماره
صفحات -
تاریخ انتشار 2005