My version of today's excercise (Hashes)

hash_bash.rb

songs = [ 
  "The Magnetic Fields - 69 Love Songs - Parades Go By",
  "The Magnetic Fields - Get Lost - Smoke and Mirrors",
  "The Magnetic Fields - Get Lost - You, Me, and the Moon",
  "The Magnetic Fields - 69 Love Songs - The Book of Love",
  "Neutral Milk Hotel - In An Aeroplane Over the Sea - Holland 1945",
  "Neutral Milk Hotel - In An Aeroplane Over the Sea - The King of Carrot Flowers"
]

music = Hash.new {|k,v| k[v] = (Hash.new {|k,v| k[v] = []})}

songs.each do |song|
  parts = song.split(" - ")
  artist = parts[0]
  album = parts[1]
  song = parts[2]
  music[artist][album] << song
end

puts music 

# => {"The Magnetic Fields"=>{"69 Love Songs"=>["Parades Go By", "The Book of Love"], "Get Lost"=>["Smoke and Mirrors", "You, Me, and the Moon"]}, "Neutral Milk Hotel"=>{"In An Aeroplane Over the Sea"=>["Holland 1945", "The King of Carrot Flowers"]}}