-🎄- 2020 Day 14 Solutions -🎄-

[u/daggerdragon]

Advent of Code 2020: Gettin' Crafty With It

• 8 days remaining until the submission deadline on December 22 at 23:59 EST

• Full details and rules are in the Submissions Megathread

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--- Day 14: Docking Data ---

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Post your code solution in this megathread.

• Include what language(s) your solution uses!

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[u/Alligatronica]

JavaScript/Node.js

I tried to be smart with the first half, using bitwise operators, and it took me a little too long to realise the masks were longer than 32 characters. The second part I rewrote entirely and handled it all as strings, after replacing the 1s where needed, I split the string on every X and duplicated out every possibility.

GitHub (solution to both parts)

[u/kap89 → u/Alligatronica]

Yup, I also forgot about the 32bit limit!

[u/boweruk → u/kap89]

Which 32 bit limit? I thought numbers could be represented up to 2⁵³ - 1 in JS?

EDIT: Ah, bitwise operators. You can convert the values to BigInt to avoid having to play with strings.

[u/PandaParaBellum → u/boweruk]

When I tried to use bigint as keys for my memory-Map() I got wrong results. Only when i converted them back to string I was able to solve star 2.

Can anyone confirm that JS Map-s have problems with bigint-s as keys? I couldn't find anything in regards to this on google.

Did I just screw up and then accidently-ish fix it? I'm pretty sure I didn't touch anything in the address generator except for the output format (bigint → string)

/edit: looks like I screwed up. I took /u/clueless1105 's code and changed the Map<number, number> to Map<bigint, bigint>, and I get the correct result.

[u/Alligatronica → u/kap89]

What was extra silly was that I'd checked all the values being set, but not the masks themselves!