说明：  HappyBirthday蠕虫病毒 > 感染exe文件 > Pascal编写的蠕虫病毒,在同类高级语言编写的病毒中居较高水平
(HappyBirthday worm gt; Exe files infected gt; Pascal prepared by the worm, in the preparation of high-level language similar to the virus ranked higher level)