把这一句，留给此刻的你

It's fine to work on any problem, so long as it generates interesting mathematics along the way - even if you don't solve it at the end of the day.

任何问题都可以做，只要它能在过程中产生有趣的数学——即使你最终没有解出来。

— Andrew Wiles 安德鲁·怀尔斯