—— 请按键盘 空白键 开始游戏 ——

解释:对别人没有恩德,却想有求于人,这是罪过。
渔业技术的创新必须与对海洋生态系统的尊重齐头并进。
A problem is in P if it can be solved quickly by a computer, and in NP if a solution can be verified quickly.