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List of problems that are in general NP-hard but have polynomial-time solution in planar graphs?

I encountered many problems that can be formulated as graph problem. It is in general NP-hard but sometimes the graph can be proved to be planar. Hence, I am interested in learning these problems and the algorithms.

So far as I know:

  1. Max cut in planar graphs
  2. Four-coloring in planar graphs
  3. Max Independent Set in cubic planar graphs

Hope someone can complete this list.

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Ivan Xiao Avatar asked Jun 21 '11 16:06

Ivan Xiao


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1 Answers

In this compendium of NP-complete problems, under planar in the index there are a good number (~25) of entries. These entries typically link to problems where planar input admits a PTAS.

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borrible Avatar answered Sep 24 '22 22:09

borrible