Acta Informatica

, Volume 55, Issue 5, pp 445–457 | Cite as

A first step in characterizing three-element codes

  • Cao Chunhua
  • Lu Qing
  • Yang Di
Original Article


It is always an interesting subject to investigate whether a three-element language is a code or not. In this paper, we consider a special class of three-element languages, where two words have the same length which is less than the length of the third word. We give a necessary and sufficient condition to state whether a three-element language in this class is a code. This result partially resolves the problem proposed by Professor H. J. Shyr in 1990s.

Mathematics Subject Classification

68Q70 68Q45 68R15 



The authors would like to thank the referees for their careful reading of the manuscript and useful suggestions.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2017

Authors and Affiliations

  1. 1.School of Mathematics and StatisticsYunnan UniversityKunmingChina
  2. 2.School of InformationYunnan University of Finance and EconomicsKunmingChina

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