Narcissistic decimal number: Difference between revisions

Line 3,210:

=={{header|OCaml}}==

~~===~~Exhaustive search (integer series)~~===~~

;Exhaustive search (integer series)

<syntaxhighlight lang="ocaml">(* ~~speed-optimized~~ ~~exponentiation; doesn't support exponents < 1 *)~~

<syntaxhighlight lang="ocaml">let narcissistic =

let rec ~~pow b~~ n =

let rec next n l p () =

let rec digit_pow_sum a n =

if n land 1 = 0

~~then~~ if n = 2 then b * b else ~~pow~~ (b * b) (n ~~lsr~~ 1)

if n < 10 then a + p.(n) else digit_pow_sum (a + p.(n mod 10)) (n / 10)

in

~~else~~ if n = 1 then b ~~else~~ b * ~~pow~~ (b * b) (n ~~lsr 1~~)

if n = l then next n (l * 10) (Array.mapi ( * ) p) ()

else if n = digit_pow_sum 0 n then Seq.Cons (n, next (succ n) l p)

let is_narcissistic n =

else next (succ n) l p ()

let rec ~~aux~~ x e =

if x < 10

then pow x e, e

else let n, l = aux (x / 10) (succ e) in n + pow (x mod 10) l, l

in

n = ~~fst~~ (~~aux~~ n 1)

next 0 10 (Array.init 10 Fun.id)

let () =

narcissistic |> Seq.take 25 |> Seq.iter (Printf.printf " %u") |> print_newline</syntaxhighlight>

Seq.(ints 0 |> filter is_narcissistic |> take 25 |> map string_of_int)

|> List.of_seq |> String.concat " " |> print_endline</syntaxhighlight>

=={{header|Oforth}}==