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🤶 - 2025 DAY 8 SOLUTIONS - 🤶
(programming.dev)
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Solution Threads
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| 8 | 9 | 10 | 11 | 12 |
Icon base by Lorc under CC BY 3.0 with modifications to add a gradient
console.log('Hello World')
Nim
view code
Runtime: 364 ms
Part 1:
I compute all pairs of Euclidean distances between 3D points, sort them, then connect points into circuits, using, what I think is called a Union‑Find algorithm (circuits grow or merge). After exactly 1000 connections (including redundant ones), I take the three largest circuits and multiply their sizes.
Part 2:
While iterating through the sorted connections, I also calculate the product of each pair x‑coordinates. The last product is a result for part 2.
Problems I encountered while doing this puzzle:
ref objects stored in a HashTable (~ 40 min)Time to solve Part 1: 1 hour 56 minutes
Time to solve Part 2: 4 minutes
Full solution at Codeberg: solution.nim
Upvote for mentioning union-find. It's the little algorithm that could, and almost nobody has heard about it.