Comment by Stratoscope

I've shared this before, but it seems relevant here:

Several years ago a Facebook recruiter invited me to interview with them. It mostly went well, except I bombed the leetcode algorithm quiz.

The next day, as I expected, they sent me a polite note thanking me for interviewing but they would be moving on with other candidates.

The morning after that, I woke up and before I opened my eyes I saw the complete solution on the back of my eyelids, about 20 lines of code.

I stepped through the code mentally and thought, "Yes! This will work!"

So I ran to my computer and typed the code in to test it. Other than one bug - this was old-school JavaScript and I'd forgotten one var statement, so there was an inadvertent global - it worked perfectly.