Random and Pseudo-Random Walks on Graphs
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چکیده
Random walks on graphs have turned out to be a powerful tool in the design of algorithms and other applications. In particular, expander graphs, which are graphs on which random walks have particularly good properties, are extremely useful in complexity and other areas of computer science. In this chapter we study random walks on general regular graphs, leading to a the randomized logspace algorithm for undirected connectivity alluded to in Chapter 7. We then show the definition and constructions of expander graphs, and their application for randomness-efficient error reduction of probabilistic algorithms. Finally we use the ideas behind that construction to show a deterministic logspace algorithm for undirected connectivity.
منابع مشابه
Random and Pseudo-Random Walks on Graphs
Random walks on graphs have turned out to be a powerful tool in the design of algorithms and other applications. In particular, expander graphs, which are graphs on which random walks have particularly good properties, are extremely useful in complexity and other areas of computer science. In this chapter we will study random walks on general graphs, leading to a the randomized logspace algorit...
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