Data commit

Task/Number-names/F-Sharp/number-names.fs

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+let divMod n d = n / d, n % d
+
+let join = String.concat ", "
+
+let rec nonzero = function
+  | _, 0 -> ""
+  | c, n -> c + (spellInteger n)
+
+and tens n =
+  [| ""; ""; "twenty"; "thirty"; "forty"; "fifty";
+             "sixty"; "seventy"; "eighty"; "ninety" |].[n]
+
+and small n =
+  [| "zero"; "one"; "two"; "three"; "four"; "five";
+     "six"; "seven"; "eight"; "nine"; "ten"; "eleven";
+     "twelve"; "thirteen"; "fourteen"; "fifteen";
+     "sixteen";"seventeen"; "eighteen"; "nineteen" |].[n]
+
+and bl = [| ""; ""; "m"; "b"; "tr"; "quadr"; "quint";
+                    "sext"; "sept"; "oct"; "non"; "dec" |]
+
+and big = function
+  | 0, n -> (spellInteger n)
+  | 1, n -> (spellInteger n) + " thousand"
+  | e, n -> (spellInteger n) + " " + bl.[e] + "illion"
+
+and uff acc = function
+  | 0 -> List.rev acc
+  | n ->
+      let a, b = divMod n 1000
+      uff (b::acc) a
+
+and spellInteger = function
+  | n when n < 0 -> "minus " + spellInteger (abs n)
+  | n when n < 20 -> small n
+  | n when n < 100 ->
+      let a, b = divMod n 10
+      (tens a) + nonzero ("-", b)
+  | n when n < 1000 ->
+      let a, b = divMod n 100
+      (small a) + " hundred" + nonzero (" ", b)
+  | n ->
+      let seg = uff [] n
+      let _, segn =
+        (* just add the index of the item in the list *)
+        List.fold
+          (fun (i,acc) v -> i + 1, (i, v)::acc)
+          (0, [])
+          seg
+
+      let fsegn =
+        (* remove right part "zero" *)
+        List.filter
+          (function (_, 0) -> false | _ -> true)
+          segn
+
+      join (List.map big fsegn)
+;;