In the
Towers of Hanoi example, the Prolog inference engine figures out how to move a stack of any number of progressively smaller disks, one at a time, from the left pole to the right pole in the described way, by means of a center as transit, so that there's never a bigger disk on top of a smaller disk. The predicate hanoi takes an integer indicating the number of disks as an initial argument. class hanoi predicates hanoi : (unsigned N). end class hanoi implement hanoi domains pole = left; center; right. clauses hanoi(N) :- move(N, left, center, right). class predicates move : (unsigned N, pole A, pole B, pole C). clauses move(0, _, _, _) :- !. move(N, A, B, C) :- move(N-1, A, C, B), stdio::writef("move a disc from % pole to the % pole\n", A, C), move(N-1, B, A, C). end implement hanoi goal console::init(), hanoi::hanoi(4). ==Reception==