Prime decomposition: Difference between revisions

 

=={{header|Elm}}==

module Main exposing (main)

 

import Html exposing (Html, div, h1, text)

import Html.Attributes exposing (style)

 

-- See live:

-- <nowiki>https://ellie-app.com/pMYxVPQ4fvca1</nowiki>

 

accumulator : List Int

accumulator =

    []

 

ts =

    showFactors compositeNr 2 accumulator

 

 

main =

        div

            [ style "margin" "5%"

            , style "font-size" "1.5em"

            , style "color" "blue"

            ]

            [ h1 [] [ text "Prime Factorizer" ]

            , text

                ("Prime factors: "

                    ++ listAsString ts

                    ++ " from number "

                    ++ String.fromInt (List.product ts)

                )

 

 

showFactors : Int -> Int -> List Int -> List Int

showFactors number factor acc =

    if number < 2 then

        acc

        -- returns the final result if number < 2

    else if

        modBy factor number == 0

        -- modulo used to get prime factors

            v2 : List Int

            v2 =

                factor :: acc

            number2 : Int

            number2 =

                number // factor

        in

        showFactors number2 factor v2

        -- recursive call

        -- this modulus function is used

        -- in order to output factor !=2

    else

        let

            factor2 : Int

            factor2 =

                factor + 1

        in

        showFactors number factor2 acc

 

listAsString : List Int -> String

listAsString myList =

    List.map String.fromInt myList

        |> List.map (\el -> " " ++ el)

        |> List.foldl (++) " "

 

</syntaxhighlight>

{{out}}

 

=={{header|Elixir}}==