A simple FPRAS for bi-directed reachability
نویسندگان
چکیده
Gorodezky and Pak (Random Struct. Algorithms, 2014) introduced a “clusterpopping” algorithm for sampling root-connected subgraphs in a directed graph, and conjectured that it runs in expected polynomial time on bi-directed graphs. We confirm their conjecture. It follows that there is a fully polynomial-time randomized approximation scheme (FPRAS) for reachability in bi-directed graphs. Reachability is the probability that, assuming each arc fails independently, all vertices can reach a special root vertex in the remaining graph. A bi-directed graph is one in which each directed arc has a parallel twin oriented in the opposite sense.
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ورودعنوان ژورنال:
- CoRR
دوره abs/1709.08561 شماره
صفحات -
تاریخ انتشار 2017