Finding Large Planar Subgraphs and Large Subgraphs of a Given Genus
نویسندگان
چکیده
We consider the MAXIMUM PLANAR SUBGRAPH problem given a graph G, nd a largest planar subgraph of G. This problem has applications in circuit layout, facility layout, and graph drawing. We improve to 4/9 the best known approximation ratio for the MAXIMUM PLANAR SUBGRAPH problem. We also consider a generalization of the previous problem, the MAXIMUM GENUS D SUBGRAPH problem-given a connected graph G, nd a maximum subgraph of G of genus at most D. For the latter problem, we present a simple algorithm whose approximation ratio is 1/4.
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