Rob2233 发表于 2017-2-23 21:45 I8 |/ T+ b' L. N @7 k
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, . {, J6 B' |# l8 h3 I# `这应该是比 ...
8 d& }* w& d. k( H' i* G: \5 Bthanks 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.