On the lattice of prefix codes
Antonio Restivo2002, Theoretical Computer Science
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Abstract
The natural correspondence between preÿx codes and trees is explored, generalizing the results obtained in Giammarresi et al. (Theoret. Comput. Sci. 205 (1998) 1459) for the lattice of ÿnite trees under division and the lattice of ÿnite maximal preÿx codes. Joins and meets of preÿx codes are studied in this light in connection with such concepts as ÿniteness, maximality and varieties of rational languages. Decidability results are obtained for several problems involving rational preÿx codes, including the solution to the primeness problem.
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