对于如下文法定义的PASCAL语言子集,试编写并上机调试一个词法分析程序:
<标识符>->字母|<标识符>字母|<标识符>数字
<无符号整数>->数字|<无符号整数>数字
<单界符>->+|-|*|/| | |:|( | )|?|>|<|=|!
<双界符>-><叹号>= | <冒号>=
<叹号>->!
<冒号>->:
For the following grammar defines a subset of the PASCAL language and try to write and debug a machine on a lexical analysis program: < identifier> -> letter | < identifier> alphabet | < identifier> number < unsigned int> -> digital | < unsigned integer> number < single delimiter > -> +|-|*|/| | |:|( | )|?|> |< |=|! < double delimiter> -> < exclamation mark> = | < colon> = < exclamation mark> -> ! < colon> -> : (2011-10-10, Visual C++, 4KB, 下载9次)