利用java语言，编写了压缩和解压程序，实现了对文本的压缩和解压。并且对字典的结构进行了改进，使用了两个字段来表示，减小了内存的使用，和运行时间。-Using java language, prepared by compression and decompression procedures, achieved on the text compression and decompression. And the structure of the dictionary has been impr