• Corpus ID: 16228406

On a classification of context-free languages

@article{Gruska1967OnAC,
  title={On a classification of context-free languages},
  author={Jozef Gruska},
  journal={Kybernetika},
  year={1967},
  volume={3},
  pages={22-29}
}
  • J. Gruska
  • Published 1967
  • Computer Science
  • Kybernetika
The set E of strings is said to be definable (strongly definable) if there is a context-free grammar G such that E is the set of all terminal strings generated from the initial symbol (from all non­ terminal symbols) of G. The classification of definable and strongly definable sets in dependence on minimal number of nonterminal symbols needed for their generation is given. 
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