Measuring Indifference: Unit Interval Vertex Deletion
نویسندگان
چکیده
Making a graph unit interval by a minimum number of vertex deletions is NP-hard. The problem is motivated by applications in seriation and measuring indifference between data items. We present a fixedparameter algorithm based on the iterative compression technique that finds in O((14k + 14)kn) time a set of k vertices whose deletion from an n-vertex graph makes it unit interval. Additionally, we show that making a graph chordal by at most k vertex deletions is NP-complete even on {claw,net,tent}-free graphs.
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Unit Interval Vertex Deletion: Fewer Vertices are Relevant
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