编制一个词法分析程序，从输入的源程序中，分析出各个具有独立意义的单词，即基本保留字、标识符、常量、运算符、界符五大类。并依次输出每类单词，错误时记下出错的行列，出错原因，然后跳过错误部分继续分析-compiled a lexical analysis procedures from the importation of the source, the analysis of the various independent significance of the word, that is to retain the basic character identifier, constants, and Operators, the industry address five major categories. And each type of output followed by the words, the wrong way down the ranks wrong, wrong reasons, then jump to the wrong part analysis