Contents

module AllYourBase exposing (rebase)

import List


fromBase : Int -> List Int -> Maybe Int
fromBase base =
    let
        f x m =
            case m of
                Nothing ->
                    Nothing

                Just n ->
                    if x >= 0 && x < base then
                        Just (n * base + x)
                    else
                        Nothing
    in
    List.foldl f (Just 0)


toBase : Int -> Int -> List Int
toBase base =
    let
        divMod a b =
            ( a // b, a % b )

        swap ( a, b ) =
            ( b, a )

        unfold f b =
            case f b of
                Just ( a, b_ ) ->
                    a :: unfold f b_

                Nothing ->
                    []

        f x =
            case x of
                0 ->
                    Nothing

                _ ->
                    Just (swap (divMod x base))
    in
    List.reverse << unfold f


rebase : Int -> List Int -> Int -> Maybe (List Int)
rebase inBase digits outBase =
    let
        length =
            List.length digits

        numZeros =
            List.length (List.filter (\x -> x == 0) digits)
    in
    if inBase < 2 || outBase < 2 || length == 0 || length == numZeros then
        Nothing
    else
        case fromBase inBase digits of
            Just v ->
                Just (toBase outBase v)

            Nothing ->
                Nothing

Version data entries

66 entries across 66 versions & 1 rubygems

Version	Path
trackler-2.2.1.180	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.179	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.178	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.177	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.176	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.175	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.174	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.173	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.172	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.171	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.170	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.169	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.167	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.166	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.165	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.164	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.163	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.162	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.161	tracks/elm/exercises/all-your-base/AllYourBase.example.elm
trackler-2.2.1.160	tracks/elm/exercises/all-your-base/AllYourBase.example.elm