Rob2233 发表于 2017-2-23 21:45 " d( R. c9 ?( R% m0 y. h; 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, 0 s% G% E H O; G这应该是比 ...
0 A. F- i. h) O) b% {thanks 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.