Bounding the Depth of Search Trees

@article{Fraenkel1993BoundingTD,
  title={Bounding the Depth of Search Trees},
  author={Aviezri S. Fraenkel and Shmuel Tomi Klein},
  journal={Comput. J.},
  year={1993},
  volume={36},
  pages={668-678}
}
For an ordered sequence of n weights, Human's algorithm constructs in time and space O(n) a search tree with minimum average path length, or, with is equivalent, a minimum redundancy code. However, if an upper bound B is imposed on the length of the codewords, the best known algorithms for the construction of an optimal code have time and space complexities O(Bn 2 ). A new algorithm is presented, which yields sub-optimal codes, but in time O(n log n) and space O(n). Under certain conditions… 
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