Rob2233 发表于 2017-2-23 21:45 6 r. _6 @$ N( S( N+ W( r. f7 j# t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,( Q3 E$ \) D5 y" P# _
这应该是比 ...
M. \0 V4 g1 ^# F% [5 M2 Jthanks 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.