程序中先判断这个句语句中每个单元为关键字、常数、运算符、界符，对与不同的单词符号给出不同编码形式的编码，用以区分之。-proceedings of the first judgment of sentence statement, the keyword for each of the modules, constant, Operators, the industry website. pairs with different words are given different symbols coding forms of coding to differentiate.