Interesting one where I get the high-level logic right, but a subtle bug has been hiding in my code since day 5, and today it comes to bite me in the ass in a very annoying manner.
ferd
Author of Property-Based Testing with PropEr, LYSE, & Erlang in Anger
NobbZ
Today was not my day…
I tried at work while waiting for CI and other people…
I spent a lot of time hunting down for unexplainable–and even worse–nonreproducable crashes of my IntcodeVM. And I didn’t even had tackled any D9 specific stuff, I was just preparing the VM to accept non-pos-mode args for “write to” arguements…
It ended in me just committing the state as it was, driving home and after lunch trying again from where I left.
Everything went smooth, I got clean match errors with nice stack traces and I could fix the issues within minutes…
In the VM code, even some try/catchs are left which I used to try to figure out whats going on…
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JEG2
Author of Designing Elixir Systems with OTP
qhwa
Ahh, [203, 0]! You are not alone, I was there too, struggling to figure out the cause of [203, 0] at some point in progress! I also store the input to the wrong address for 203. I’m as excited as you when I saw you got it working. 
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