A Linear-Time Approximation Algorithm for Rotation Distance
نویسندگان
چکیده
Rotation distance between rooted binary 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 this short note, we give an efficient, linear-time approximation algorithm, which estimates the rotation distance, within a provable factor of 2, between ordered rooted binary trees. Submitted: July 2009 Reviewed: August 2009 Revised: August 2010 Accepted: August 2010 Final: August 2010 Published: November 2010 Article type: Concise paper Communicated by: T. Warnow Research supported by Grants NSF #0811002 to Cleary and NSF #0513660 and #0920920 to St. John. E-mail addresses: [email protected] (Sean Cleary) [email protected] (Katherine
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عنوان ژورنال:
- J. Graph Algorithms Appl.
دوره 14 شماره
صفحات -
تاریخ انتشار 2010