Rotation Distance is Fixed-Parameter Tractable
نویسندگان
چکیده
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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عنوان ژورنال:
- Inf. Process. Lett.
دوره 109 شماره
صفحات -
تاریخ انتشار 2009