there are 2 policemen and 2 thieves on Auk island
they want to get the thieves to Bik island, from there they will take
and ferry to the mainland but the boat is small and can only take
2 at a time ...the thieves are dangerous ..how do they cross?
put a police man and theif
then the police man stays behind and the theif goes back
then the other theif gets on and the 2 theives go to the island and then one theif stays and the other goes back and the police officer gets on and goes to the island with the theif