Representations of Edge Intersection Graphs of Paths in a Tree
نویسندگان
چکیده
Let P be a collection of nontrivial simple paths in a tree T . The edge intersection graph of P , denoted by EPT (P), has vertex set that corresponds to the members of P , and two vertices are joined by an edge if the corresponding members of P share a common edge in T . An undirected graph G is called an edge intersection graph of paths in a tree, if G = EPT (P) for some P and T . The EPT graphs are useful in network applications. Scheduling undirected calls in a tree or assigning wavelengths to virtual connections in an optical tree network are equivalent to coloring its EPT graph.
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