On Local Structures of Cubicity 2 Graphs
نویسندگان
چکیده
A 2-stab unit interval graph (2SUIG) is an axes-parallel unit square intersection graph where the unit squares intersect either of the two fixed lines parallel to the X-axis, distance 1 + (0 < < 1) apart. This family of graphs allow us to study local structures of unit square intersection graphs, that is, graphs with cubicity 2. The complexity of determining whether a tree has cubicity 2 is unknown while the graph recognition problem for unit square intersection graph is known to be NPhard. We present a polynomial time algorithm for recognizing trees that admit a 2SUIG representation.
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