一个问题如果在计算机上可以快速解决,那么它属于P类问题;如果一个解可以快速验证,那么它属于NP类问题。
Life is a journey, and if you fall in love with the journey, you will be in love forever.
The rise of a new great power is always a cause for concern among existing powers, as it threatens the existing balance of power.