On the decidability of the valuedness problem for two-way finite transducers
Journal
Information and Computation
Journal Volume
285
Date Issued
2022
Author(s)
Yen D.-D
Abstract
A transducer is infinite-valued if the maximal number of different outputs for an input string is not bounded by any constant. For one-way finite transducers, sufficient and necessary conditions exist in terms of the structure of a transducer to characterize whether the transducer is infinite-valued or not, yielding the decidability result of the finite-valuedness problem. As crossing sequences in two-way automata often play similar roles as states in their one-way counterparts, we consider analogous criteria in the setting of crossing sequences to characterize the infinite-valuedness of two-way finite transducers. The characterization leads to a decidability proof for the valuedness problem of two-way finite transducers. © 2022 Elsevier Inc.
Subjects
Crossing sequence; Finite transducer; Valuedness
Other Subjects
Transducers; Crossing sequence; Finite transducers; Input string; Sufficient and necessary condition; Two ways; Two-way automata; Valuedness; Computability and decidability
Type
journal article