这是几个小的flash课件,用于应付老师罢了,包括粉笔字,雨的形成等-This is the flash several small courseware for teachers to cope with the ILO that include chalk, the formation of rain

北大密码学课程的课件~密码学基础1-4 讲得通俗易懂。适合初学者自学使用。也可用来辅助读加解密程序或者编程。