Todd Ginsberg

Problem Statement Quick, without thinking too hard about it, what would you expect this code to print for the date 2025-12-28?

Well today, Day 12, is the last day of Advent of Code 2025.

Today we’ll write our first Depth-First search algorithm of this year’s Advent of Code!

I ended up getting some help from /r/adventofcode on Reddit to solve part 2.

Today we’ll depend on a data structure called a Disjoint Set.

I enjoyed this puzzle!

This has been my favorite puzzle of Advent of Code 2025 so far!

I love how in Advent of Code we can drive a forklift through a wall so our Elf friends can get to the cafeteria more easily, completely unconcerned about collateral damage or injury.

Of all the various types of problems we tend to see during Advent of Code, the grid-based puzzles are among my favorite.

When doing fix-it work at home, I’m usually pretty reluctant to get involved with electricity, being that it can kill you and whatnot.