How well can Primal - Dual and Local - Ratio algorithms perform ? ∗ Allan
نویسندگان
چکیده
We define an algorithmic paradigm, the stack model, that captures many primal dual and local ratio algorithms for approximating covering and packing problems. The stack model is defined syntactically and without any complexity limitations and hence our approximation bounds are independent of the P vs NP question. Using the stack model, we bound the performance of a broad class of primal dual and local ratio algorithms and supply a (log n+1)/2 inapproximability result for set cover, a 4/3 inapproximability for min Steiner tree, and a 0.913 inapproximability for interval scheduling on two machines.
منابع مشابه
How well can Primal-Dual and Local-Ratio algorithms
We define an algorithmic paradigm, the stack model, that captures many primal-dual and local-ratio algorithms for approximating covering and packing problems. The stack model is defined syntactically and without any complexity limitations and hence our approximation bounds are independent of the P vs NP question. We provide tools to bound the performance of primal dual and local ratio algorithm...
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