An Optimal Algorithm for Prufer Codes

Xiaodong Wang, Lei Wang, Yingjie Wu

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DOI: 10.4236/jsea.2009.22016                

Abstract

This paper studies the algorithms for coding and decoding Prufer codes of a labeled tree. The algorithms for coding and decoding Prufer codes of a labeled tree in the literatures require time usually. Although there exist linear time algorithms for Prufer-like codes [1,2,3], the algorithms utilize the integer sorting algorithms. The special range of the integers to be sorted is utilized to obtain a linear time integer sorting algorithm. The Prufer code problem is reduced to integer sorting. In this paper we consider the Prufer code problem in a different angle and a more direct manner. We start from a naïve algorithm, then improved it gradually and finally we obtain a very practical linear time algorithm. The techniques we used in this paper are of interest in their own right.

Keywords

Design of Algorithm, Labeled Trees, Prufer Codes, Integer Sorting

Conflicts of Interest

The authors declare no conflicts of interest.

References

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