examples/benchmarks/portland/hanoi.pl

/*  VAX C-Prolog Benchmark Package  */
/*  Copyright 1985 by Tektronix, Inc., and Portland State University  */

hanoi(N) :- move(N,left,center,right).
move(0,_,_,_) :- !.
move(N,A,B,C) :- M is N-1, move(M,A,C,B), move(M,C,B,A).