gistfile1.rb

class Processor
  BLUE_HOSTS = [
    'hoge.jp', 'grey.jp', 'hoge.com'
  ]
  def process(lines)
    lines.each do |line|
      if blue? line
        blue_lines << line
      else
        red_lines << line
      end
  end
private
  def blue?(line)
    blue_hosts.each do |blue_host|
      return true if line.index(blue_host)
    end
    false
  end

end

Processor.new.process(lines)