🎄 Here are my solutions to the Advent of Code 2021 challenges! 🎄
You're minding your own business on a ship at sea when the overboard alarm goes off! You rush to see if you can help. Apparently, one of the Elves tripped and accidentally sent the sleigh keys flying into the ocean!
Before you know it, you're inside a submarine the Elves keep ready for situations like this. It's covered in Christmas lights (because of course it is), and it even has an experimental antenna that should be able to track the keys if you can boost its signal strength high enough; there's a little meter that indicates the antenna's signal strength by displaying 0-50 stars.
Your instincts tell you that in order to save Christmas, you'll need to get all fifty stars by December 25th.
Collect stars by solving puzzles. Two puzzles will be made available on each day in the Advent calendar; the second puzzle is unlocked when you complete the first. Each puzzle grants one star. Good luck!
| M | T | W | T | F | S | S |
|---|---|---|---|---|---|---|
| - | - | 1 | 2 | 3 | 4 | 5 |
| 6 | 7 | 8 | 9 | 10 | 11 | 12 |
| 13 | 14 | 15 | 16 | 17 | 18 | 19 |
| 20 | 21 | 22 | 23 | 24 | 25 | - |
Difficulty explanation: S (Simple), M (Medium), D (Difficult), - (Haven't solved yet, can not judge). The difficulty is always in an A/B format, which expresses the difficulty of part 1 (A) and part 2 (B).
| Day | Difficulty | Keywords |
|---|---|---|
| 1 | S/S | Number/Sum comparison |
| 2 | S/S | Working with coordinates |
| 3 | S/S | Finding most/least common strings |
| 4 | S/S | Finding the best/worst bingo board |
| 5 | S/S | Counting crossings |
| 6 | S/M | Loops/Logical maths |
| 7 | S/S | Logical maths/Loops |
| 8 | S/H | Loops, decoding |
| 9 | S/M | Finding lowest number from neighbours, getting area within borders |
| 10 | S/S | Detecting incorrect sequences, completing sequences |
| 11 | S/S | Process simulation |
| 12 | S/S | Finding all paths |
| 13 | S/S | Folding paper, finding overlaps |
| 14 | S/M | Process simulation |
| 15 | S/S | Pathfinding |
| 16 | H/H | Decoding |
| 17 | S/S | Process simulation |
| 18 | -/- | - |
| 19 | -/- | - |
| 20 | -/- | - |
| 21 | -/- | - |
| 22 | -/- | - |
| 23 | -/- | - |
| 24 | -/- | - |
| 25 | -/- | - |