Bipartite graph matchings in the semi-streaming model

Abstract

We present an algorithm for finding a large matching in a bipartite graph in the semi-streaming model. In this model, the input graph G=(V, E) is represented as a stream of its edges in some arbitrary order, and storage of the algorithm is bounded by O(n , polylog n) bits, where n=|V|. For ε>0, our algorithm finds a 1/1+ε -approximation of a maximum-cardinality matching and uses O((1/ε)8passes over the input stream. The only previously known algorithm with such arbitrarily good approximation - though for general graphs - required exponentially many ω((1/ε) 1/ε) passes (McGregor 2005). © 2009 Springer Berlin Heidelberg.