编制C++语言子集的词法分析程序 根据具体情况，由同学们自己选取C语言的一个适当大小的子集（可取一类典型单词，也可以尽可能使各种类型的单词都兼顾到）-Preparation C++ language subset of lexical analysis procedures depending on the circumstances, by the students themselves select an appropriately sized C language subset (pr