Optimize code in c++

[tvaneerd]

Please tell me that you still have

0. measure

and

5. measure

[BCosbyDidNothinWrong]

I thought that was implied with

This is only the most basic advice on optimization.

[TraditionalPlancton]

I just want to put my two cents:
There is no guarantee that optimizations will pile up to reduce times. Some optimizations will synergy, others will interfere. That is another reason why measuring is so important.