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arXiv · 1204.5801

Optimal Prefix Free Code in Linear Time

Jérémy Barbay
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Abstract

We describe an algorithm computing an optimal prefix free code from $N$ unsorted positive integer weights in time linear in the number of machine words holding those weights. This algorithm takes advantage of common non-algebraic instructions, and of specific results on optimal prefix free codes. This result improves over the state of the art complexities of $O(N\lg N)$ in the algebraic decision tree model and $O(N\lg\lg N)$ in the RAM model for the computation of Huffman's codes, a landmark in compression and coding since 1952.

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Jérémy Barbay. 2012-04-26. Optimal Prefix Free Code in Linear Time. https://arxiv.org/abs/1204.5801

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