SaaS-Class: Homework 1

advanced_oop.rb

class Class
  
  def attr_accessor_with_history(attr_name)
    attr_name = attr_name.to_s         # make sure it's a string
    attr_reader attr_name              # create the attribute's getter
    attr_reader attr_name + "_history" #create history getter
    class_eval %{
      def #{attr_name}=(val)
        @#{attr_name} = val
        @#{attr_name}_history = [nil] if @#{attr_name}_history.nil?
        @#{attr_name}_history.push(val)
      end
    }
  end
  
end

class Foo
  
  attr_accessor_with_history :bar

end

f = Foo.new
f.bar = 1
f.bar = 2
f = Foo.new
f.bar = 4
p f.bar_history

anagram.rb

class Anagram
  
  def self.combine(words)
    
    anagrams = words.uniq.inject Hash.new [] do |anagrams, word|
      
      group = word.chars.sort.join
      
      anagrams[group] += [word] if group == word.chars.sort.join
      anagrams
      
    end
    
    anagrams.values #Output as array
    
  end
  
end

p Anagram.combine(['cars', 'for', 'potatoes', 'racs', 'four','scar', 'creams', 'scream'])

basic_oop.rb

class Dessert
  
  attr_accessor :name
  attr_accessor :calories
  
  def initialize(name, calories)
    @name = name
    @calories = calories
  end
  
  def healthy?
    @calories < 200
  end
  
  def delicious?
    true
  end
  
end

class JellyBean < Dessert
  
  attr_accessor :flavor
  
  def initialize(name, calories, flavor)
    @name = name
    @calories = calories
    @flavor = flavor
  end
  
  def delicious?
    @flavor == 'black licorice' ? false : true
  end
  
end

dessert = Dessert.new('cheesecake',250)
p dessert.delicious?
p dessert.healthy?

bean = JellyBean.new('bertiebots',150,'cinnamon')
p bean.delicious?
p bean.healthy?

calisthenics.rb

class String
  
  def palindrome?
    
    self.gsub!(/\W+/, '').downcase!
    
    self == self.reverse
    
  end
  
  def word_count
    downcase.split.inject Hash.new(0) do |count, word|
        count[word] +=1
        count
    end
  end

end

print "A man, a plan, a canal -- Panama".palindrome?
print "Doo bee doo bee doo".word_count

rock_paper_scissors.rb

class WrongNumberOfPlayersError < StandardError ; end 
class NoSuchStrategyError < StandardError ; end

class RockPaperScissors
  
  def rps_game_winner(game)
    raise WrongNumberOfPlayersError unless game.length == 2

    game.each do |player, strategy|
      raise NoSuchStrategyError unless ['R','P','S'].include?(strategy.upcase)
    end
    
    if compare?(game)
      puts game[0][0] + " Wins!"
      game[0]
    else
      puts game[1][0] + " Wins!"
      game[1]
    end
    
  end
  
  def rps_tournament_winner(game)
    if game[0][1].class==String
      rps_game_winner(game)
    else
      branch1=rps_tournament_winner(game[0])
      branch2=rps_tournament_winner(game[1])
      rps_tournament_winner([branch1,branch2])
    end
  end
  
  def compare?(game)
    (game[0][1] + game[1][1]) =~ /rs|sp|pr|rr|ss|pp/i
  end
  
end

game = RockPaperScissors.new

list = [ [ "Armando", "P" ], [ "Dave", "S" ] ]

game.rps_game_winner(list)

tournament = [ [
                [ [ "Armando", "P" ], [ "Dave", "S" ] ],
                [ [ "Richard", "R"], ["Michael", "S"] ], 
               ],
               [
                 [ ["Allen", "S"], ["Omer", "P"] ],
                 [ ["David E.", "R"], ["Richard X.", "P"] ]
              ] ]

game.rps_tournament_winner(tournament)