11_classes.rb

# Write a program that outputs the lyrics for "Ninety-nine Bottles of Beer on the Wall"
# Your program should print the number of bottles in English, not as a number. For example:
#
# Ninety-nine bottles of beer on the wall,
# Ninety-nine bottles of beer,
# Take one down, pass it around,
# Ninety-eight bottles of beer on the wall.
# ...
# One bottle of beer on the wall,
# One bottle of beer,
# Take one down, pass it around,
# Zero bottles of beer on the wall.
#
# Your program should not use ninety-nine output statements!
# Design your program with a class named BeerSong whose initialize method
# receives a parameter indicating the number of bottles of beer initially on the wall.
# If the parameter is less than zero, set the number of bottles to zero. Similarly,
# if the parameter is greater than 99, set the number of beer bottles to 99
# Then make a public method called print_song that outputs all stanzas from the number of bottles of beer down to zero.
# Add any additional methods you find helpful.

class BeerSong
attr_accessor :beers

def initialize(beers)
  beers = 0 if beers < 0
  beers = 99 if beers > 99
  self.beers = beers
end

def print_song
  beers.downto 1 do |i|
    print_stanza i
  end
end

def print_stanza(n)
  if n.zero?
    String.new
  else
    puts "#{translate n} #{bottle n} of beer on the wall,"
    "#{translate n} #{bottle n} of beer,"
    "Take on down, pass it around,"
    "#{translate n - 1} #{bottle n - 1} of beer on the wall."
  end
end

def bottle(n)
  if n == 1 then 'bottle' else 'bottles' end
  end

  def translate(n)
    if 0 <= n && n <= 19
      %w(zero one two three four five six seven eight nine ten eleven twelve thirteen fourteen fiftenn sixteen seventeen eighteen nineteen)
    elseif n % 10 == 0
    %w(zero ten twenty thirty forty fifty sixty seventy eigthy ninety)[n/10]
  else
    "#{translate n/10*10}-#{translate n%10}".downcase
  end.capitalize
end
end