## Advent of Code 2021 Day 19

## Solve for X where:

`X = the number of beacons`

## Our input is:

- A multi-line string

## The input represents:

- A collection of nearly 40 scanners
- For each one, a list of ~25
`x,y,z`

coordinates... - ...one for each beacon's location relative to that scanner...
- ...and only of the subset of beacons that are positioned within a 1,000 point 3D perimeter

## What makes this challenge difficult

- As stated above, only relative positions are given
- We don't know the exact positions of any scanners
- Of the ~25 beacons per scanner, only 12 coordinates will overlap with one other scanner's beacons

## What makes this challenge exponentially more difficult

- Each of the scanners could be in any of 24 rotations and orientations around each of the
`x,y,z`

axes

## All of the ways I felt intimidated by this challenge

- The description was the longest encountered in the series thus far, even after Days 23 and 25
- This reminded me of Day 22, in which I recall throwing in the towel after failing to grasp any sort of possible solution
- I struggle to visualize 3D areas without having photographic references.
- The thought of looping through each scanner's coordinate list and comparing each one to every other scanner's full coordinate list seemed inefficient, sloppy and wrong...but I can't think of any other way to solve this
- The anticipated arithmetic, geometry and physics seemingly involved in calculating distances and validating a variety of object alignments
- I couldn't even understand the example offered in the instructions, or how the author's conclusions were correct or arrived upon
- The Reddit Solution Megathread for this day housed comments that confirmed my lack of STEM knowledge likely required to even understand a solution to this challenge, let alone writing an algorithm that could solve it, too

## Pressing skip for my own wellbeing

I'm not prepared, or excited, to attempt this puzzle right now.

And since this isn't homework, nor am I being graded - in fact, this is supposed to be a fun project to keep my mind sharp - I vote to skip to the next (nay, previous) day.

Sad face now. But it's important to admit when you're not mentally equipped to attempt a puzzle.

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