Look-and-say sequence: Difference between revisions

Another solution using the pcre bindings:

<lang ocaml>open Pcre

let lookandsay str =

let rex = regexp "(.)\\1*" in

let subs = exec_all ~rex str in

let ar = Array.map (fun sub -> get_substring sub 0) subs in

let ar = Array.map (fun s -> String.length s, s.[0]) ar in

let ar = Array.map (fun (n,c) -> (string_of_int n) ^ (String.make 1 c)) ar in

let res = String.concat "" (Array.to_list ar) in

(res)

let () =

let num = ref(string_of_int 1) in

for i = 1 to 10 do

num := lookandsay !num;

print_endline !num;

done</lang>