Approximating the Crossing Number of Toroidal Graphs
نویسندگان
چکیده
CrossingNumber is one of the most challenging algorithmic problems in topological graph theory, with applications to graph drawing and VLSI layout. No polynomial time approximation algorithm is known for this NP-Complete problem. We give in this paper a polynomial time approximation algorithm for the crossing number of toroidal graphs with bounded degree. In course of proving the algorithm we present a new structural “grid” theorem for toroidal graphs.
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