3-Colourability of Dually Chordal Graphs in Linear Time
نویسنده
چکیده
A graph G is dually chordal if there is a spanning tree T of G such that any maximal clique of G induces a subtree in T . This paper investigates the Colourability problem on dually chordal graphs. It will show that it is NP-complete in case of four colours and solvable in linear time with a simple algorithm in case of three colours. In addition, it will be shown that a dually chordal graph is 3-colourable if and only if it is perfect and has no clique of size four.
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عنوان ژورنال:
- CoRR
دوره abs/1206.0233 شماره
صفحات -
تاریخ انتشار 2012