Rob2233 发表于 2017-2-23 21:45! B4 M% u, [; v4 Q
如果觉得难度不够的话,可以试试加拿大公开赛(Canadian Open Mathematics Challenge)的题, / j5 h9 w8 A! e8 w% h v这应该是比 ...
, b; e2 s- r" l" ?% H" b6 Qthanks a lot as parents, but i guess my daughter going to hate you. i won't let her know who you are. please keep sending this kind good resource for all parents.