通过这道程序的编写，进一步加深了对AES的理解，也了解了模块化设计的基本思想，编程的时候，把一个大任务分解是很重要的，针对相应的子任务所编写的一段功能独立的代码或一个功能模块，在程序设计时，我们可以把程序中功能相对独立的模块用函数来实现。这样做，不仅可以使程序条理清晰，便于维护。而且，通过重复使用某些函数，可以节省软件开发时间。对一个大问题先从一个大的全局上去考虑，分成几个大的模块，将每个大的模块进一步分解。该程序就是这样的思想，将加密分成三大步骤，对第二大步骤的9次循环的每次都要进行4个操作。编程时就先编出小模块，然后就可以很顺利的编出大的模块。这样可以节约编程的时间。-Road through this program, further deepening the understanding of AES, understand the modular design of the basic idea, programming time, a major task decomposition is very important. in light of the corresponding sub-tasks of the section prepared by the functional independence of code or a function module, in the process, we can process relatively independent of the functional modules use the function to be achieved. To do so, so that procedures can not only lucid, easy to maintain. Furthermore, by the repeated use of some functions, the software can save development time. A big problem for the benefit of a big boost to the overall consideration, divided into several major modules, each of the major modules further decomposition. The program is the idea of encryption is divided into three