instances block 1..10. % 3 % 5 10 % 2 8 6 % 1 7 4 9 %------------------ initially loc(3)=5. loc(5)=8. loc(10)=6. loc(2)=1. loc(8)=7. loc( 6)=4. goals loc(B)=B+1 :- B<10. % a tower from 1 to 10 loc(10)=table.