一个人的伟大不在于他获得了多少财富，而在于他的正直和他积极影响周围人的能力。

Every problem in NP can be reduced to the satisfiability problem, which is the cornerstone of computational complexity theory.

"You never really understand a person until you consider things from his point of view."

写书的职业使赛马看起来像是一个稳固、稳定的生意。