midterm1-fall12-blank

Let test bool = =(intersperse run_test"" test

Info iconThis preview shows pages 2–7. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: let test () : bool = _________ = (intersperse _________ _______________________) ;; run_test "___________________________________________________" test iv. let test () : bool = _________ = (intersperse _________ _______________________) ;; run_test "___________________________________________________" test 2 (12 points) Step 4 is implementing the program . Fill in the body of the intersperse function to com- plete the design. Do not use any list library functions (such as fold , or @ ) to solve this problem. If you would like to use a helper function in your answer, you must define it. let rec intersperse (c:______________) (l:______________) : ______________ = 3 2. List Processing (20 points) For each of the following programs, write the value computed for r : a. let rec h (l:int list) : int = begin match l with | -> 0 | x::xs -> x * (h xs) end let r : int = h [1;2;3] b. let rec g (l:’a list) : ’a list = begin match l with | -> | [x] -> [x] | x::y::xs -> if x < y then x::(g (y::xs)) else y::(g (x::xs)) end let r : int list = g [1;3;2;0] c. let rec f (p: ’a -> bool) (l:’a list) : ’a list * ’a list = begin match l with | -> (, ) | x::xs -> let (l,r) = f p xs in if p x then (x::l, r) else (l, x::r) end let r : (int list * int list) = f ( fun (x:int) -> x > 0) [0;1;2;-3;4] 4 The last two programs refer to the following definitions. let rec transform (f: ’a -> ’b) (x: ’a list): ’b list = begin match x with | -> | h :: t -> (f h) :: (transform f t) end let rec fold (combine: ’a -> ’b -> ’b) (base: ’b) (x: ’a list): ’b = begin match x with | -> base | h :: t -> combine h (fold combine base t) end d. let k (x: ’a list) : ’a list = fold ( fun (h:’a) (v:’a list) -> v @ [h]) x let r : int list = k [1;3;2;4] e. let j (x : int list list) : int list = let transformer (l:int list) : int = fold ( fun (x:int) (v:int) -> x + v) 0 l in transform transformer x let r : int list = j [[1;2;3];[4;5];] 5 3. Types (16 points) For each OCaml value or function definition below, fill in the blank where the type annotation could go or write “ill typed” if there is a type error. If an expression can have multiple types, givecould go or write “ill typed” if there is a type error....
View Full Document

{[ snackBarMessage ]}

Page2 / 10

let test bool = =(intersperse run_test"" test iv...

This preview shows document pages 2 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online