简单的词法、语法分析器

(1,void) (2,main) (26,() (27,)) (30,{) (3,char) (10,a) (32,,) (10,b) (33,;) (4,if) (10,a) (37,>=) (10,b) (5,then) (10,a) (21,=) (10,b) (33,;) (6,do) (30,{) (10,a) (22,+) (22,+) (33,;) (31,}) (10,while) (26,() (10,a) (36,<) (20,100) (33,;) (31,})