词法分析器，每个循环处理一个单词；调用词法分析过程；输出每个单词的内部码（种别编码，属性值）。建议从文件中读取要分析的符号串。-Lexical analyzer, each cycle dealing with a word　lexical analysis procedure calls　the output of each internal code word (species not coding, property values). I recommend reading the string of symbols to be analyzed　the file.