自己写一个SHA1算法类源代码，和流传的比较广泛的VB版本的MD5的代码比较下

　　就能发现里面的轮转的2种写法

　　1种用的是循环赋值，比较简捷

　　另1种则是把循环打开了，便于调试

　　2种写法各有优劣-Write a SHA1 algorithm class source code, and the spread of the more extensive version of the MD5 VB code can be found under more inside rotation of the two kinds of one kind of written assignment using a loop, the other one kind of simple comparison is to cycle open, easy to debug two kinds of formulation advantages and disadvantages. . .