Subj : Re: any function to handle this kind of counting?
To   : comp.programming
From : Jon Harrop
Date : Sat Jul 30 2005 04:56 am

Jon Harrop wrote:
> Here is an array-based implementation:

  let ab = Array.of_list (List.combine a b) in
  let max_a = ref 0 and max_b = ref '\000' in
  Array.iter (fun (a, b) -> max_a := max !max_a a; max_b := max !max_b b)
ab;
  let max_a = !max_a and max_b = int_of_char !max_b in
  let m = Array.init (max_a + 1)
    (fun _ -> Array.init (max_b + 1) (fun _ -> ref 0)) in
  Array.iter (fun (a, b) -> incr m.(a).(int_of_char b)) ab;

-- 
Dr Jon D Harrop, Flying Frog Consultancy
http://www.ffconsultancy.com

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