六个数字有多少种组合不重复简介：Xie Ningtian's class is a parallel class. She is among the top in the class, but if she wants to enter the top class, there is still a big gap between her current grades.
Xie Ningtian's class is a parallel class. She is among the top in the class, but if she wants to enter the top class, there is still a big gap between her current grades.
