Generalizations of code languages with marginal errors

Yo Sub Han, Sang Ki Ko, Kai Salomaa

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

2 Scopus citations


We study k-prefix-free, k-suffix-free and k-infix-free languages that generalize prefix-free, suffix-free and infix-free languages by allowing marginal errors. For example, a string x in a k-prefix-free language L can be a prefix of up to k different strings in L. Namely, a code (language) can allow some marginal errors. We also define finitely prefix-free languages in which a string x can be a prefix of finitely many strings. We present efficient algorithms that determine whether or not a given regular language is k-prefix-free, k-suffix-free or k-infix-free, and analyze their runtime. Lastly, we establish the undecidability results for (linear) context-free languages.

Original languageEnglish
Title of host publicationDevelopments in Language Theory - 19th International Conference, DLT 2015, Proceedings
EditorsIgor Potapov
PublisherSpringer Verlag
Number of pages12
ISBN (Print)9783319214993
StatePublished - 2015
Event19th International Conference on Developments in Language Theory, DLT 2015 - Liverpool, United Kingdom
Duration: 27 Jul 201530 Jul 2015

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Conference19th International Conference on Developments in Language Theory, DLT 2015
Country/TerritoryUnited Kingdom


  • Codes
  • Context-free languages
  • Decision algorithms
  • Marginal errors
  • Regular languages
  • Undecidability


Dive into the research topics of 'Generalizations of code languages with marginal errors'. Together they form a unique fingerprint.

Cite this