Advent of Code 2025 - Day 10

A bit of linear programming on my birthday, how lovely! Read the full prompt. Part 1 My idea for solving Part 1 was to represent the lights as a Set of numbers, and then use the use newly available symmetricDifference method to toggle the lights on and off. Doing setA.symmetricDifference(setB) will return numbers which are in either setA or setB , but not both . So for a set of lights lights :=…