Abstract
We show that the problem of constructing a perfect matching in a graph is in the complexity class Random NC; i.e., the problem is solvable in polylog time by a randomized parallel algorithm using a polynomial-bounded number of processors. We also show that several related problems lie in Random NC. These include:
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(i)
Constructing a perfect matching of maximum weight in a graph whose edge weights are given in unary notation;
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(ii)
Constructing a maximum-cardinality matching;
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(iii)
Constructing a matching covering a set of vertices of maximum weight in a graph whose vertex weights are given in binary;
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(iv)
Constructing a maximums-t flow in a directed graph whose edge weights are given in unary.
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Research supported by NSF Grant # DCR-8411954.
Research supported by a Weizmann Post-Doctoral fellowship, and by DARPA Grant N00039-83-C-1036.
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Karp, R.M., Upfal, E. & Wigderson, A. Constructing a perfect matching is in random NC. Combinatorica 6, 35–48 (1986). https://doi.org/10.1007/BF02579407
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DOI: https://doi.org/10.1007/BF02579407