artists_albums_songs.rb

class Artist 
  def initialize(name)
    @name = name
    @albums = []
  end

  def add_album(album)
    @albums.push(album)
  end
end

class Album
  def initialize(title, date)
    @title = title
    @date = date
    @songs = []
  end

  def add_song(song)
    @songs << song
  end
end

class Song
  def initialize(title, duration, genre)
    @title = title
    @duration = duration
    @genre = genre
  end
end

eminem = Artist.new('Eminem')
a_bocelli = Artist.new('Andrea Bocelli')

encore = Album.new("Encore","07/03/2004")
relaspe = Album.new("Relaspe","09/09/2000")

puke = Song.new("Puke", "4min7sec", "hiphop")
my_mum = Song.new("My mum", "5min19sec", "hiphop")

eminem.add_album(encore)
encore.add_song(puke)
encore.add_song(my_mum)
pp eminem