The secret of living is to own a convertible and a lake...If the sun is shining, you can rid around in your convertible and be happy...If it starts to rain, it won't spoil your day because you can just say, 'Oh, well, the rain will fill up my lake!'"”

A problem is in P if it can be solved quickly by a computer, and in NP if a solution can be verified quickly.

你无法阻止浪潮，但你可以学会冲浪。