pelegri (04/07/83)
Fernando Pereira's solution to the zebra problem certainly has some typographical errors. I think it is a good example to check how easy is to find and fix bugs in whatever PROLOG you have (even though that may not have been the intention). Once I fixed the bugs it ran correctly on both the DEC-10 Prolog and in the UNSW Prolog. In my opinion the major difference between the two presented solutions is the way the solution space is searched: the permutation approach used by Lewis Baxter is more efficient. This was particularly noticeable in UNSW Prolog running in an always loaded Vax-780. ed. (ucbvax!pelegri)