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# Project Euler #017

If the numbers 1 to 5 are written out in words: one, two, three, four, five, then there are 3 + 3 + 5 + 4 + 4 = 19 letters used in total. If all the numbers from 1 to 1000 (one thousand) inclusive were written out in words, how many letters would be used?

``````let dictionary =
[
(1000, "one thousand");
(90, "ninety");
(80, "eighty");
(70, "seventy");
(60, "sixty");
(50, "fifty");
(40, "forty");
(30, "thirty");
(20, "twenty");
(19, "nineteen");
(18, "eighteen");
(17, "seventeen");
(16, "sixteen");
(15, "fifteen");
(14, "fourteen");
(13, "thirteen");
(12, "twelve");
(11, "eleven");
(10, "ten");
(9, "nine");
(8, "eight");
(7, "seven");
(6, "six");
(5, "five");
(4, "four");
(3, "three");
(2, "two");
(1, "one");
];

let rec translate (n:int) : string =
if n = 0 then
System.String.Empty
elif dictionary |> List.exists (fun (x, s) -> x = n) then
snd (dictionary |> List.find (fun (x, s) -> n = x)) + " "
else
let log10 x = x |> float |> System.Math.Log10 |> System.Math.Truncate
let first_number x = System.Math.Truncate((x |> float) / (10.0 ** log10 x))
let part x = (first_number x) * 10.0 ** log10 x |> int

if 2.0 = log10 n then
let rest = translate (n - part n)
translate (first_number n |> int) + "hundred " + if System.String.IsNullOrWhiteSpace(rest) then "" else "and " + rest
else
(translate (part n)) + (translate (n - (part n)))

(List.fold (fun acc n -> acc + translate n) "" [1..1000]).Replace(" ", System.String.Empty).Length
``````
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