Finding Skew Partitions Efficiently
نویسندگان
چکیده
A skew partition as defined by Chvátal is a partition of the vertex set of a graph into four nonempty parts A B C D such that there are all possible edges between A and B and no edges between C and D. We present a polynomial-time algorithm for testing whether a graph admits a skew partition. Our algorithm solves the more general list skew partition problem, where the input contains, for each vertex, a list containing some of the labels A B C D of the four parts. Our polynomialtime algorithm settles the complexity of the original partition problem proposed by Chvátal in 1985 and answers a recent question of Feder, Hell, Klein, and Motwani. © 2000 Academic Press
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