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arXiv · 1901.03783

On Huang and Wong's Algorithm for Generalized Binary Split Trees

Marek Chrobak·Mordecai Golin·J. Ian Munro·Neal E. Young
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Abstract

Huang and Wong [1984] proposed a polynomial-time dynamic-programming algorithm for computing optimal generalized binary split trees. We show that their algorithm is incorrect. Thus, it remains open whether such trees can be computed in polynomial time. Spuler [1994] proposed modifying Huang and Wong's algorithm to obtain an algorithm for a different problem: computing optimal two-way-comparison search trees. We show that the dynamic program underlying Spuler's algorithm is not valid, in that it does not satisfy the necessary optimal-substructure property and its proposed recurrence relation is incorrect. It remains unknown whether the algorithm is guaranteed to compute a correct overall solution.

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Marek Chrobak, Mordecai Golin, J. Ian Munro, Neal E. Young. 2019-01-12. On Huang and Wong's Algorithm for Generalized Binary Split Trees. https://doi.org/10.1007/s00236-021-00411-z

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