English

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

Data Structures and Algorithms 2022-02-15 v4

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.

Keywords

Cite

@article{arxiv.1901.03783,
  title  = {On Huang and Wong's Algorithm for Generalized Binary Split Trees},
  author = {Marek Chrobak and Mordecai Golin and J. Ian Munro and Neal E. Young},
  journal= {arXiv preprint arXiv:1901.03783},
  year   = {2022}
}
R2 v1 2026-06-23T07:09:33.756Z