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arXiv · 0903.0197

Rotation Distance is Fixed-Parameter Tractable

Sean Cleary·Katherine St. John
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Abstract

Rotation distance between trees measures the number of simple operations it takes to transform one tree into another. There are no known polynomial-time algorithms for computing rotation distance. In the case of ordered rooted trees, we show that the rotation distance between two ordered trees is fixed-parameter tractable, in the parameter, k, the rotation distance. The proof relies on the kernalization of the initial trees to trees with size bounded by 7k.

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Sean Cleary, Katherine St. John. 2009-03-02. Rotation Distance is Fixed-Parameter Tractable. https://arxiv.org/abs/0903.0197

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