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-Design and implement a lexical analyzer to achieve the reading of the class C language source text file to specify the location and the ability of the source of all the words are classified, indicate the type to which it belongs, simple lexical analysis operation.