Question

2a

Please code in Ocaml:

TODO: Implement an OCaml function sum_top_4 : int list -> int list, which takes a list of integers and adds the sum of the top four elements to the head of the list (e.g. the input list [1;1;1;1;3;2] should become the output list [4;1;1;1;1;3;2]).

starter code:

let sum_top_4 (xs : int list) : int list = (* your work here *) [ ]

Answer 1

Answer :

let sum_top_k   =

fun arg -> let list = [1;1;1;1;3;2] in

let rec sum_top_k k =

if k=1 then list.(0)

else list.(k-1) + sum_top_k (k-1)

in sum_top_k arg ; ;

sum_first_k 4 ;;

( * int - : int = 4 *)