(*
   Problems 1 through 4:  no library functions 
   Problems 5 through 10: no explicit recursion

   (Skeleton version 2.0)
*)

(* Problem 1 *)
let rec range inc a b = raise(Failure("Function not defined yet."))

(* Problem 2 *)
let rec zip_app flst lst = raise(Failure("Function not defined yet."))

(* Problem 3 - must be tail recursive *)
let count_true f lst = raise(Failure("Function not defined yet."))

(* Problem 4 - must be tail-recursive *)
let rev_map f lst = raise(Failure("Function not defined yet."))

(* Problem 5 *)
let range_int a b = raise(Failure("Function not defined yet."))

(* Problem 6 *)
let reverse lst = raise(Failure("Function not defined yet."))

(* Problem 7 *)
let graph_arg f x = raise(Failure("Function not defined yet."))

(* Problem 8 *)
let inverse_arg (x, y) = raise(Failure("Function not defined yet."))

(* Problem 9 - must use List.fold_left *)
let catlist lst = raise(Failure("Function not defined yet."))

(* Problem 10 - must use List.fold_right *)
let compose lst = raise(Failure("Function not defined yet."))

(* Problem 11 - Extra Credit *)
let rec find_min lst = raise(Failure("Function not defined yet."))
let rec sort lst = raise(Failure("Function not defined yet."))