# No sublogarithmic-time approximation scheme for bipartite vertex cover

@article{Gs2012NoSA, title={No sublogarithmic-time approximation scheme for bipartite vertex cover}, author={Mika G{\"o}{\"o}s and Jukka Suomela}, journal={Distributed Computing}, year={2012}, volume={27}, pages={435-443} }

König’s theorem states that on bipartite graphs the size of a maximum matching equals the size of a minimum vertex cover. It is known from prior work that for every $$\epsilon > 0$$ϵ>0 there exists a constant-time distributed algorithm that finds a $$(1+\epsilon )$$(1+ϵ)-approximation of a maximum matching on bounded-degree graphs. In this work, we show—somewhat surprisingly—that no sublogarithmic-time approximation scheme exists for the dual problem: there is a constant $$\delta > 0$$δ>0 so…

## 13 Citations

### Approximate Bipartite Vertex Cover in the CONGEST Model

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### Approximating Bipartite Minimum Vertex Cover in the CONGEST Model

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König’s theorem states that on bipartite graphs the size of a maximum matching equals the size of a minimum vertex cover. It is known from prior work that for every ϵ>0\documentclass[12pt]{minimal}…

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