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vonnenaut's solution

to Scrabble Score in the Ruby Track

Published at Dec 26 2019 · 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.

For installation and learning resources, refer to the Ruby resources page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

gem install minitest

If you would like color output, you can require 'minitest/pride' in the test file, or note the alternative instruction, below, for running the test file.

Run the tests from the exercise directory using the following command:

ruby scrabble_score_test.rb

To include color from the command line:

ruby -r minitest/pride scrabble_score_test.rb

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_score_test.rb

require 'minitest/autorun'
require_relative 'scrabble_score'

class ScrabbleTest < Minitest::Test
  def test_empty_word_scores_zero
    assert_equal 0, Scrabble.new('').score
  end

  def test_whitespace_scores_zero
    skip
    assert_equal 0, Scrabble.new(" \t\n").score
  end

  def test_nil_scores_zero
    skip
    assert_equal 0, Scrabble.new(nil).score
  end

  def test_scores_very_short_word
    skip
    assert_equal 1, Scrabble.new('a').score
  end

  def test_scores_other_very_short_word
    skip
    assert_equal 4, Scrabble.new('f').score
  end

  def test_simple_word_scores_the_number_of_letters
    skip
    assert_equal 6, Scrabble.new('street').score
  end

  def test_complicated_word_scores_more
    skip
    assert_equal 22, Scrabble.new('quirky').score
  end

  def test_scores_are_case_insensitive
    skip
    assert_equal 41, Scrabble.new('OXYPHENBUTAZONE').score
  end

  def test_convenient_scoring
    skip
    assert_equal 13, Scrabble.score('alacrity')
  end
end
# scrabble_score.rb
# PEDAC practice #43

# Problem
# Examples/Test Cases
# Data Structure
# Algorithm
# Code


# Problem & Examples
#####################
=begin
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.
=end


# Data Structure
##################
# input -- a string
# output -- a score totaled from the values of each letter in the string


# Algorithm
###############
=begin
1. Create a hash with a string containing all the letters of one value as the key and that value as its value.
2. Instantiate total = 0
3. split the string into letters and iterate through them, checking which key string contains each letter and retrieving its value, adding it to score.
4. return the total score
=end


# Code
#########
class Scrabble
  def initialize(string)
    @string = string
  end

  def self.get_score(letter)
    scores = {
      'AEIOULNRST' => 1,
      'DG'  => 2,
      'BCMP' => 3,
      'FHVWY' => 4,
      'K' => 5,
      'JX' => 8,
      'QZ' => 10
    }

    scores.keys.each do |key|
      return scores[key] if key.include? letter.upcase
    end
    return 0
  end

  def self.score(string = @string)
    return 0 if ['', nil].include? string
    total = 0
    letters = string.split(//)    
    letters.map! { |letter| self.get_score(letter) }
    letters.each { |score| total += score }
    total
  end

  def get_score(letter)
    scores = {
      'AEIOULNRST' => 1,
      'DG'  => 2,
      'BCMP' => 3,
      'FHVWY' => 4,
      'K' => 5,
      'JX' => 8,
      'QZ' => 10
    }

    scores.keys.each do |key|
      return scores[key] if key.include? letter.upcase
    end
    return 0
  end

  def score(string = @string)
    return 0 if ['', nil].include? string
    total = 0
    letters = string.split(//)    
    letters.map! { |letter| get_score(letter) }
    letters.each { |score| total += score }
    total
  end
end

# Test Cases
#############
p Scrabble.new('').score == 0
p Scrabble.new(" \t\n").score == 0
p Scrabble.new(nil).score == 0
p Scrabble.new('a').score == 1
p Scrabble.new('f').score == 4
p Scrabble.score('alacrity') == 13

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