1 // towers of hanoi in Fun

     2 

     3 let rec hanoi = fun n a b c ->

     4   if n != 0 then (

     5     hanoi (n - 1) a c b;

     6     print_endline ("Move disk from pole " ^ (show a) ^ " to pole " ^ (show b));

     7     hanoi (n - 1) c b a

     8   ) else ();;

     9 

    10 impure $ hanoi 4 1 2 3;;