L04-weighted - We ighte BipartiteMatching d Le cture4: Jan...

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1 Weighted Bipartite Matching Lecture 4: Jan 18
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2 Weighted Bipartite Matching Given a weighted bipartite graph, find a matching with maximum total weight. Not necessarily a maximum size matching. A B
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3 Today’s Plan Three algorithms negative cycle algorithm primal dual algorithm augmenting path algorithm Applications
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4 First Algorithm How to know if a given matching M is optimal? Idea: Imagine there is a larger matching M* and consider the union of M and M* Find maximum weight perfect matching
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5 First Algorithm Orient the edges (edges in M go up, others go down) edges in M having positive weights, otherwise negative weights Then M is maximum if and only if there is no negative cycles
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6 First Algorithm Key: M is maximum no negative cycle How to find efficiently?
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7 Complexity At most nW iterations A negative cycle in time by Floyd Warshall Total running time Can choose minimum mean cycle to avoid W
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8 Augmenting Path Algorithm Orient the edges (edges in M go up, others go down)
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This note was uploaded on 10/13/2009 for the course CS 5150 taught by Professor Xulei during the Spring '09 term at University of Central Arkansas.

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L04-weighted - We ighte BipartiteMatching d Le cture4: Jan...

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