1 wrong answer to test 4 not interesting duplicate 1

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

View Full Document Right Arrow Icon
-1 wrong answer to test -4 not “interesting” (duplicate) -1 poor or no description (i.e. description just states what the test case is, not why it was interesting.) 2
Image of page 2

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

View Full Document Right Arrow Icon
(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:’a) (l:’a list) : ’a list = begin match l with | [] -> [] | [x] -> [x] | x::xs -> x::c::(intersperse c xs) end Grading scheme: no deduction for minor syntax errors -2 incorrect Nil case -3 incorrect Singleton case -5 Not recursing/pattern matching on correct list various other errors at discretion 3
Image of page 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] 0 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] [1;2;0;3] 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] ([1;2;4], [0;-3]) 4
Image of page 4

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

View Full Document Right Arrow Icon
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] [4;2;3;1] 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];[]] [6;9;0] Grading scheme, each answer worth four points: no deduction for minor syntax errors 1 point if the value is of the correct type 2 points (part c) if structure is correct 4 points if completely correct Other minors errors -1 to -4 at discretion (e.g. -1 point per wrong list item/wrong order) 5
Image of page 5
3. Types (16 points)
Image of page 6

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

View Full Document Right Arrow Icon
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern