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Space Complexity of Perfect Matching in Bounded Genus Bipartite Graphs Datta, Samir Kulkarni, Raghav Tewari, Raghunath Vinodchandran, N. Variyam perfect matching bounded genus graphs isolation problem We investigate the space complexity of certain perfect matching problems over bipartite graphs embedded on surfaces of constant genus (orientable or non-orientable). We show that the problems of deciding whether such graphs have (1) a perfect matching or not and (2) a unique perfect matching or not, are in the logspace complexity class SPL. Since SPL is contained in the logspace counting classes oplus L (in fact in mod_k for all k >= 2), C=L, and PL, our upper bound places the above-mentioned matching problems in these counting classes as well. We also show that the search version, computing a perfect matching, for this class of graphs is in FL^SPL. Our results extend the same upper bounds for these problems over bipartite planar graphs known earlier. As our main technical result, we design a logspace computable and polynomially bounded weight function which isolates a minimum weight perfect matching in bipartite graphs embedded on surfaces of constant genus. We use results from algebraic topology for proving the correctness of the weight function. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Samir Datta and Raghav Kulkarni and Raghunath Tewari and N. Variyam Vinodchandran 2011 Is Part Of LIPIcs, Volume 9, 28th International Symposium on Theoretical Aspects of Computer Science (STACS 2011) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.STACS.2011.579 urn:nbn:de:0030-drops-30450 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.STACS.2011.579 eng https://creativecommons.org/licenses/by-nc-nd/3.0/legalcode