Binary (generalized) Post Correspondence Problem. (English) Zbl 1023.03038

We give a new proof for the decidability of the binary Post Correspondence Problem (PCP) originally proved in 1982 by A. Ehrenfeucht, J. Karhumäki and G. Rozenberg [Theor. Comput. Sci. 21, 119-144 (1982; Zbl 0493.68076)]. Our proof is complete and somewhat shorter than the original proof although we use the same basic idea.


03D40 Word problems, etc. in computability and recursion theory
03B25 Decidability of theories and sets of sentences
68Q45 Formal languages and automata


Zbl 0493.68076
Full Text: DOI


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