# list0402.rb
# 単純継承の例

class Work
  def initialize(author,title,date)
    @author = author
    @title = title
    @date = date
  end
  def what
    print "題目：", @title, "\n"
  end
  def whose
    print "作者：", @author, "\n"
  end
  def when
    print "日付：",@date,"\n"
  end
end

class Paper < Work
  def initialize(author,title,date,contents)
    @author = author
    @title = title
    @date = date
    @document = contents
  end
  def show
    print "内容：",@document,"\n"
  end
end

x = Paper.new('鳥大太郎','はじめてのRuby','2002.10.22','Hello World!')
x.what
x.whose
x.when
x.show