1、构造该算符优先文法的优先关系矩阵或优先函数；
2、输入串应是词法分析的输出二元式序列，即某算术表达式“实验项目一”的输出结果。输出为输入串是否为该文法定义的算术表达式的判断结果。
3、算符优先分析过程应能发现输入串出错。
-1, construction of the operator the priority of the priority relation matrix grammar or priority function 2, input strings should be the output of lexical analysis of binary sequence, that is, the arithmetic expression of a
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001085s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.072408s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001253s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001498s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001179s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.004028s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000982s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.004825s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.018237s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001257s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 112371 [ RunTime:0.021990s ]
