The earliest memory I have of ‘programming’ is in the early/mid 90s when my father brought home a computer from work. We could play games on it … so of course I took the spreadsheet program he used (LOTUS 123, did I date myself with that?) and tried to modify it to print out a helpful message for him. It … halfway worked? At least I could undo it so he could get back to work…

After that, I picked up programming for real in QBASIC (I still have a few of those programs lying around), got my own (junky) Linux desktop from my cousin, tried to learn VBasic (without a Windows machine), and eventually made it to high school… In college, I studied computer science and mathematics, mostly programming in Java/.NET, although with a bit of everything in the mix. A few of my oldest programming posts on this blog are from that time.

After that, on to grad school! Originally, I was going to study computational linguistics, but that fell through. Then programming languages (the school’s specialty). And finally I ended up studying censorship and computer security. That’s about where I am today!

But really, I still have a habit of doing a little bit of everything. Whatever seems interesting at the time!

AoC 2024 Day 14: Chaosinator

Source: Day 14: Restroom Redoubt

Full solution for today (spoilers!).

Part 1

Given a series of robots defined with initial position and velocity on a 101x103 toroidal grid, calculate where the robots will be after 100 iterations. Return the product of the number of robots in each quadrant of the final grid, ignoring the middle lines (since they’re odd).

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AoC 2024 Day 11: Exponential Growthinator

Source: Day 11: Plutonian Pebbles

Full solution for today (spoilers!).

Part 1

Given a sequence of values v_n, replace each value with the first matching rule:

  • if v = 0 -> 1
  • If v has an even number of digits, split it (so v = 8675 becomes [86, 75])
  • Otherwise, v -> v * 2024

Calculate how many elements are in the sequence after 25 iterations.

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AoC 2024 Day 9: Defraginator

Source: Day 9: Disk Fragmenter

Full solution for today (spoilers!).

Part 1

Given a disk layout alternating between files and empty spaces, move all files as early on the disk is possible, splitting into multiple blocks. Return a checksum on the disk.

Alternating means: 23331 would mean a 2 block file, 3 empty, a 3 block file, 3 empty, and a 1 block file.

The checksum is the sum of file_id * block_index for all occupied blocks. File IDs are assigned sequentially on initial generation.

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AoC 2024 Day 6: Wanderinator

Source: Day 6: Guard Gallivant

Full solution for today (spoilers!).

Part 1

You are given a grid of walls (#), floors (.), and a guard (^, initially facing up/north). The guard walks forward until they run into a wall at which point they turn right. How many tiles does the guard reach before leaving the map.

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