English

Optimal Test Sets for Context-Free Languages

Formal Languages and Automata Theory 2016-11-22 v1

Abstract

A test set for a formal language (set of strings) L is a subset T of L such that for any two string homomorphisms f and g defined on L, if the restrictions of f and g on T are identical functions, then f and g are identical on the entire L. Previously, it was shown that there are context-free grammars for which smallest test sets are cubic in the size of the grammar, which gives a lower bound on tests set size. Existing upper bounds were higher degree polynomials; we here give the first algorithm to compute test sets of cubic size for all context-free grammars, settling the gap between the upper and lower bound.

Keywords

Cite

@article{arxiv.1611.06703,
  title  = {Optimal Test Sets for Context-Free Languages},
  author = {Mikaël Mayer and Jad Hamza},
  journal= {arXiv preprint arXiv:1611.06703},
  year   = {2016}
}
R2 v1 2026-06-22T16:58:56.268Z