emma roberts wrote:but what I can not understand why the increment in the signature method change the value of the i but normally all change in the signature method and body is not considered outside the addTwo
What are you referring to as the "signature method"? It's not clear what you're confused about. Was there something in Dave's explanation that you did not understand?
The best ideas are the crazy ones. If you have a crazy idea and it works, it's really valuable.—Kent Beck