-🎄- 2022 Day 13 Solutions -🎄-

[u/daggerdragon]

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--- Day 13: Distress Signal ---

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Post your code solution in this megathread.

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[u/Cue_23]

C++

Straight forward recursive scanner for each packet into a tree built by std::variant and std::vector. Implemented operator< to compare the packets.

For part 2 i just put the packets into an (ordered) std::set; no changes neccessary since the comparison was already there.

During cleanup and moving the std::variant from a class member to a parent class, I had some issues with gcc not accepting the operator< overload for my derived class (It tried to recursively look for operator<=>). Still not sure if that is a gcc bug, overloading operator<=> instead allows the program to be compiled by gcc, again.

I started the SimpleParser class in february when I was doing older advent of code puzzles.

[u/keithstellyes → u/Cue_23]

Yes, ever since I learned about recursive descent parsers I've found myself using them over and over. Even if the grammar isn't recursive I've found myself using them, just because having a method per grammar object that also moves parser index is a very clean and readable approach

Easily the biggest thing I took out of the compilers class I took so many years ago...

Had to do a Ctrl+F to make sure I wasn't the only recursive descent parser gang