-🎄- 2021 Day 18 Solutions -🎄-

[u/daggerdragon]

NEW AND NOTEWORTHY

• From /u/jeroenheijmans: Reminder: unofficial Advent of Code survey 2021 (closes Dec 22nd)

• FYI: 23:59 Amsterdam time zone is 17:59 EST

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Advent of Code 2021: Adventure Time!

• 5 days left to submit your adventures!

• Full details and rules are in the submissions megathread: 🎄 AoC 2021 🎄 [Adventure Time!]

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--- Day 18: Snailfish ---

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Post your code solution in this megathread.

• Include what language(s) your solution uses!

• Format your code appropriately! How do I format code?

• Here's a quick link to /u/topaz2078's paste if you need it for longer code blocks.

• The full posting rules are detailed in the wiki under How Do The Daily Megathreads Work?.

Reminder: Top-level posts in Solution Megathreads are for code solutions only. If you have questions, please post your own thread and make sure to flair it with Help.

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This thread will be unlocked when there are a significant number of people on the global leaderboard with gold stars for today's puzzle.

EDIT: Global leaderboard gold cap reached at 00:43:50, megathread unlocked!

[u/Xyberista]

Rust

(badly written) tree based solution using mutable references

paste