Source: Day 20: Race Condition

Full solution for today (spoilers!).

Part 1

Given a maze with exactly one path, find how many single walls you can walk through (remove) that shorten the best path by at least 100 units.

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Source: Day 18: RAM Run

Full solution for today (spoilers!).

Part 1

You are given a series of points on a 71x71 grid. Taking only the first 1024 points, how long is the shortest path from (0, 0) to (70, 70)?

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Source: Day 16: Reindeer Maze

Full solution for today (spoilers!).

Part 1

Given a maze, what is the shortest path between S and E where walking straight costs one and turning costs 1000.

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Source: Proboscidea Volcanium

Part 1

Given a graph of nodes, some of which have a pressure (per tick output value) and an agent that can move through the graph and activate specific nodes (so that they output their per tick value every future tick), what is the maximum total output possible in 30 steps?

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Source: Amphipod

Part 1: Given 4 rooms full of amphipods with various energy costs for movement (a=1, b=10, c=100, d=1000) and a hallway, how much energy does it take (at minimum) to sort the amphipods into their own rooms with the following conditions:

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Source: Chiton

Part 1: Given a grid of weights, find the minimum path from top left to top right. Return the total weight along that path.

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Source: Passage Pathing

Part 1: Given a list of edges in a bi-directional graph, count the number of paths from start to end such that nodes named with lowercase letters are visited once, and nodes with uppercase letters can be visited any number of times.

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