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rootulp's solution

to Scrabble Score in the Elm Track

Published at Jul 13 2018 · 0 comments
Instructions
Test suite
Solution

Note:

This solution was written on an old version of Exercism. The tests below might not correspond to the solution code, and the exercise may have changed since this code was written.

Given a word, compute the scrabble score for that word.

Letter Values

You'll need these:

Letter                           Value
A, E, I, O, U, L, N, R, S, T       1
D, G                               2
B, C, M, P                         3
F, H, V, W, Y                      4
K                                  5
J, X                               8
Q, Z                               10

Examples

"cabbage" should be scored as worth 14 points:

  • 3 points for C
  • 1 point for A, twice
  • 3 points for B, twice
  • 2 points for G
  • 1 point for E

And to total:

  • 3 + 2*1 + 2*3 + 2 + 1
  • = 3 + 2 + 6 + 3
  • = 5 + 9
  • = 14

Extensions

  • You can play a double or a triple letter.
  • You can play a double or a triple word.

Elm Installation

Refer to the Exercism help page for Elm installation and learning resources.

Writing the Code

The first time you start an exercise, you'll need to ensure you have the appropriate dependencies installed.

$ elm-package install --yes

Execute the tests with:

$ elm-test

Automatically run tests again when you save changes:

$ elm-test --watch

As you work your way through the test suite, be sure to remove the skip <| calls from each test until you get them all passing!

Source

Inspired by the Extreme Startup game https://github.com/rchatley/extreme_startup

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

Tests.elm

module Tests exposing (..)

import Expect
import ScrabbleScore exposing (scoreWord)
import Test exposing (..)


tests : Test
tests =
    describe "Grains"
        [ test "lowercase letter" <|
            \() -> Expect.equal 1 (scoreWord "a")
        , skip <|
            test "uppercase letter" <|
                \() -> Expect.equal 1 (scoreWord "A")
        , skip <|
            test "valuable letter" <|
                \() -> Expect.equal 4 (scoreWord "f")
        , skip <|
            test "short word" <|
                \() -> Expect.equal 2 (scoreWord "at")
        , skip <|
            test "short, valuable word" <|
                \() -> Expect.equal 12 (scoreWord "zoo")
        , skip <|
            test "medium word" <|
                \() -> Expect.equal 6 (scoreWord "street")
        , skip <|
            test "medium, valuable word" <|
                \() -> Expect.equal 22 (scoreWord "quirky")
        , skip <|
            test "long, mixed-case word" <|
                \() -> Expect.equal 41 (scoreWord "OxyphenButazone")
        , skip <|
            test "english-like word" <|
                \() -> Expect.equal 8 (scoreWord "pinata")
        , skip <|
            test "non-english letter is not scored" <|
                \() -> Expect.equal 7 (scoreWord "piñata")
        , skip <|
            test "empty input" <|
                \() -> Expect.equal 0 (scoreWord "")
        ]

elm-package.json

{
    "version": "3.0.0",
    "summary": "Exercism problems in Elm.",
    "repository": "https://github.com/exercism/elm.git",
    "license": "BSD3",
    "source-directories": [
        ".",
        ".."
    ],
    "exposed-modules": [],
    "dependencies": {
        "elm-lang/core": "5.0.0 <= v < 6.0.0",
        "elm-community/elm-test": "4.0.0 <= v < 5.0.0"
    },
    "elm-version": "0.18.0 <= v < 0.19.0"
}
module ScrabbleScore exposing (..)

scoreLetter: Char -> number
scoreLetter char =
    if List.member char ['A', 'E', 'I', 'O', 'U', 'L', 'N', 'R', 'S', 'T'] then
        1
    else if List.member char ['D', 'G'] then
        2
    else if List.member char ['B', 'C', 'M', 'P'] then
        3
    else if List.member char ['F', 'H', 'V', 'W', 'Y'] then
        4
    else if List.member char ['K'] then
        5
    else if List.member char ['J', 'X'] then
        8
    else if List.member char ['Q', 'Z'] then
        10
    else
        0


scoreWord: String -> number
scoreWord word =
    String.toUpper word
        |> String.toList
        |> List.map scoreLetter
        |> List.sum

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