Non-closure under complementation for unambiguous linear grammars
نویسندگان
چکیده
The paper demonstrates the non-closure of family unambiguous linear languages (that is, those defined by context-free grammars) under complementation. To be precise, a particular grammar is presented, and it proved that complement this language not any grammar. This also constitutes an alternative proof for result Hibbard Ullian (“The independence inherent ambiguity from complementedness among languages”, JACM, 1966) on
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ژورنال
عنوان ژورنال: Information & Computation
سال: 2023
ISSN: ['0890-5401', '1090-2651']
DOI: https://doi.org/10.1016/j.ic.2023.105031