(*
   This program illustrates how to define mutually recursive functions.  Note
the keyword "and".
*)


let rec f = function
  | n when n%2=0 -> f(n-1)
  | n -> g(n-1)
and g = function
  | x when x<1 -> 1
  | x when x%2=1 -> f(x-1)
  | x -> g(x-1);;


printfn "%d\n" (f(10));;  // use extra ()s when calling curried functions.