A Coloring Algorithm for $4K_1$-free line graphs
نویسندگان
چکیده
Let L be a set of graphs. Free(L) is the set of graphs that do not contain any graph in L as an induced subgraph. It is known that if L is a set of four-vertex graphs, then the complexity of the coloring problem for Free(L) is known with three exceptions: L = {claw, 4K1}, L = {claw, 4K1, co-diamond}, and L = {C4, 4K1}. In this paper, we study the coloring problem for Free(claw, 4K1). We solve the coloring problem for a subclass of Free(claw, 4K1) which contains the class of 4K1-free line graphs. Our result implies the chromatic index of a graph with no matching of size four can be computed in polynomial time.
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عنوان ژورنال:
- CoRR
دوره abs/1506.05719 شماره
صفحات -
تاریخ انتشار 2015