O ( √ log n ) Approximation to Sparsest Cut in Õ ( n 2 ) Time
نویسندگان
چکیده
We show how to compute O( √ logn)-approximations to Sparsest Cut and Balanced Separator problems in Õ(n) time, thus improving upon the recent algorithm of Arora, Rao and Vazirani (2004). Their algorithm uses semidefinite programming and required Õ(n) time. Our algorithm relies on efficiently finding expander flows in the graph and does not solve semidefinite programs. The existence of expander flows was also established by Arora, Rao, and Vazirani.
منابع مشابه
O ( √ log n ) approximation to SPARSEST CUT can be found in Õ ( n 2 ) time
We show that the recent results for obtaining O( √ log n)-approximation to sparsest cut and balanced separator problems due to Arora, Rao, and Vazirani (2004) can be used to derive an Õ(n) time approximation algorithm for an n-node graph. The previous best algorithm needed to solve a semidefinite program with O(n) constraints. Our algorithm relies on efficiently finding expander flows in the gr...
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