You're saying that the blog's solution is time efficient. Which it is not. Your solution may be O(1) but it is also not efficient. As I'm sure you are aware.

I can tell you a practical solution which is also O(1) and takes up maybe 2 or 3 instructions of program code and no extra memory at all.

`x & 1` or `x % 2 != 0`

This blog post was taking a joke and running with it. And your comment is in that spirit as well, I just wanted to point out that it's by no means time efficient when we have 2s or 1s complement numbers which make this algorithm trivial.