牛顿差商与差分计算函数，用C语言实现，设计了多个子函数，代码略长，可供参考-Newton" s difference quotient and the difference calculation functions, using C language implementation, design a number of subroutine, the code slightly longer available for reference
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001313s ]
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:0.091638s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001270s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001212s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.004120s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001070s ]
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SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.015205s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001316s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 187599 [ RunTime:0.001341s ]
