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

解释：苦味食物走骨，骨病的人不宜多食，体现了中医五味与五脏的关系。

"The best stories are the ones that make you think, that stay with you long after you've finished reading them."

人生幸福的三大要素是：有事可做，有人可爱，有希望可期待。