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rewritten's solution

to Scrabble Score in the Elixir Track

Published at Sep 30 2020 · 0 comments
Instructions
Test suite
Solution

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.

Running tests

Execute the tests with:

``````\$ mix test
``````

Pending tests

In the test suites, all but the first test have been skipped.

Once you get a test passing, you can unskip the next one by commenting out the relevant `@tag :pending` with a `#` symbol.

For example:

``````# @tag :pending
test "shouting" do
assert Bob.hey("WATCH OUT!") == "Whoa, chill out!"
end
``````

Or, you can enable all the tests by commenting out the `ExUnit.configure` line in the test suite.

``````# ExUnit.configure exclude: :pending, trace: true
``````

If you're stuck on something, it may help to look at some of the available resources out there where answers might be found.

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.

scrabble_test.exs

``````defmodule ScrabbleTest do
use ExUnit.Case

# @tag :pending
test "empty word scores zero" do
assert Scrabble.score("") == 0
end

@tag :pending
test "whitespace scores zero" do
assert Scrabble.score(" \t\n") == 0
end

@tag :pending
test "scores very short word" do
assert Scrabble.score("a") == 1
end

@tag :pending
test "scores other very short word" do
assert Scrabble.score("f") == 4
end

@tag :pending
test "simple word scores the number of letters" do
assert Scrabble.score("street") == 6
end

@tag :pending
test "complicated word scores more" do
assert Scrabble.score("quirky") == 22
end

@tag :pending
test "scores are case insensitive" do
assert Scrabble.score("OXYPHENBUTAZONE") == 41
end

@tag :pending
test "convenient scoring" do
assert Scrabble.score("alacrity") == 13
end
end``````

test_helper.exs

``````ExUnit.start()
ExUnit.configure(exclude: :pending, trace: true)``````
``````defmodule Scrabble do
@doc """
Calculate the scrabble score for the word.
"""
@spec score(String.t()) :: non_neg_integer
def score(word) do
word
|> String.upcase()
|> to_charlist()
|> Enum.map(fn
c when c in 'AEIOULNRST' -> 1
c when c in 'DG' -> 2
c when c in 'BCMP' -> 3
c when c in 'FHVWY' -> 4
c when c in 'K' -> 5
c when c in 'JX' -> 8
c when c in 'QZ' -> 10
_ -> 0
end)
|> Enum.reduce(0, &Kernel.+/2)
end
end``````