Be regretting your own mistakes，and strive not to repeat，this is true repentance.
悔恨自己的错误，而且力求不再重蹈覆辙，这才是真正的悔悟。
The concept of polynomial-time reduction is central to understanding the structure of NP-complete problems.
A book is a mirror: if an ass peers into it, you can't expect an apostle to look out.
The advance of technology is based on making it fit in so that you don't really even notice it, so it's part of everyday life.
自信不是"他们会喜欢我"，而是"他们不喜欢我也没关系"。
技术可以放大优秀教学的效果，但无法替代糟糕的教学。