xiān / qiú / chū / shí / èr / hé / shí / bā / de / zuì / dà / gōng / yuē / shù / zài / jìn / xíng / xià / yí / bù / jì / suàn

先求出12和18的最大公约数，再进行下一步计算。

First find the greatest common divisor of 12 and 18, then continue with the calculation.