1、根据要求写出词法分析的正规文法G；2、根据正规文法G，写出正则式RE；3、根据正则式RE，画出NFA；4、将NFA转化为DFA；5、将DFA转化为mininum state DFA；6、mininum state DFA就是词法分析程序的流程图，根据此流程图编写相应的词法分析程序。-1, according to the lexical analysis required to write a formal grammar G　2, according to a regular grammar G, write a regular expression RE　3, according to the regular expression RE, draw the NFA　4, the NFA into a DFA　5, the DFA conversion the mininum state DFA　6, mininum state DFA is the lexical analysis process flow chart, flow chart according to the preparation of the corresponding lexical analyzer.