Polarity and Monopolarity of $3$-colourable comparability graphs
نویسنده
چکیده
We sharpen the result that polarity and monopolarity are NP-complete problems by showing that they remain NP-complete if the input graph is restricted to be a 3-colourable comparability graph. We start by presenting a construction reducing 1-3-SAT to monopolarity of 3-colourable comparability graphs. Then we show that polarity is at least as hard as monopolarity for input graphs restricted to a fixed disjoint-union-closed class. We conclude the paper by stating that both polarity and monopolarity of 3-colourable comparability graphs are NPcomplete problems.
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ورودعنوان ژورنال:
- CoRR
دوره abs/1604.00905 شماره
صفحات -
تاریخ انتشار 2016