in reply to
What if you use
I like your approach and I think this is what you meant:
This seems the most straightforward to me. I have a personal preference of hex over octal.
Update: Oops. At first I only saw JavaFan's pack approach in the reply below this. Be he already covered this approach too. Sorry for duplicates.
By rote learning.
Via Genetic memory.
It's provided by my firmware.
I just remember them.
Thirty days hath September
My computer gets it right, usually.
I just ask someone else.
Someone punches me on the first of the month.
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