关于词法分析的一份实验报告，设计并实现一个词法分析器，实现对指定位置的类C语言源程序文本文件的读取，并能够对该源程序中的所有单词进行分类，指出其所属类型，实现简单的词法分析操作。(lexical analyzer is designed and implemented to read the text files of the class C source program of the specified location, and classify all the words in the source program, point out its type, and achieve simple lexical analysis operation.)