Introduction - If you have any usage issues, please Google them yourself
Complete the following grammar describes the word s lexical analysis program symbols, the grammar is as follows:
<Identifier >-->< letter> | <identifier> <letter> | <identifier> <number>
<Unsigned integer >-->< number> | <unsigned int> <number>
<Delimiter >-->+|-|*|/| |(|)|{|}|<|<=|=|!=|>=|>|:=|< spaces>
<Letter>-> a | ... | z | A | ... | Z
<Number>-> 0 | ... | 9
<Space >-->
Description:
(1) assumes that the language of the letters are not case sensitive, specify the file read by the pre-analysis of the source code analysis and then write to the specified file
(2) assumes that the language of the keyword "begin", "if", "end", "else", "then", "for", "while", "to", "do", "and", " not "," or "," write "
(3) The procedural requirements on behalf of output with KeyWord keyword, Word on behalf of common identifiers, Digit behalf of the Arab figures, SingleWor