caml-urm

diff --git a/urm.ml b/urm.ml
@@ -11,14 +11,14 @@ type machine =
     registers : nat -> nat;
   }
 
-let from_registers (f : int -> int) : machine =
+let from_registers f =
   { intruction_pointer = 0;
     registers = f
   }
 
-let zero : machines = from_registers (fun _ -> 0)
+let zero = from_registers (fun _ -> 0)
 
-let register (m : machine) (i : int) : int = m.registers i
+let register m = m.registers 
 
 (** Executes the next instruction. Returns [Some _] is the instruction pointer
  points to a valid adress and [None] otherwise. *)
@@ -48,12 +48,12 @@ let step (program : instruction array) (m : machine) : machine option =
         { m with instruction_pointer = m.instruction_pointer + 1 } 
     in Some updated
 
-let rec exec (program : instruction array) (m : machine) : machine =
+let rec exec program m =
   match step program m with
   | None -> { m with instruction_pointer = 0 }
   | Some n -> exec program n
 
-let exec_safe program (m : machine) (max : int) : machine option =
+let exec_safe program m max =
   if max <= 0 
   then raise (Invalid_argument "the number of clock-cycles must be positive ")
   else