AoC 2024 Day 13: Cramerinator

2024-12-13

Source: Day 13: Claw Contraption

Full solution for today (spoilers!).

Part 1

Given Button A (ax, ay), Button B (bx, by), and Prize (px, py); how many times must you press Button A (a) and Button B (b) to reach the Prize? Sum 3a + b for each machine that has a solution.

AoC 2024 Day 7: Mathinator

2024-12-07

Source: Day 7: Bridge Repair

Full solution for today (spoilers!).

Part 1

Given a result and a list of numbers, determine if any combination of addition (+) and/or multiplication (*) using all the given numbers in order can return the result. Ignore order of operations.

StackLang Part VII: New CLI and Datatypes

2023-08-05

Another day, another Stacklang! Posts in StackLang: StackLang Part I: The Idea StackLang Part II: The Lexer StackLang Part III: The Parser StackLang Part IV: An Interpreter StackLang Part V: Compiling to C StackLang Part VI: Some Examples StackLang Part VII: New CLI and Datatypes StackLang Part VIII: Compiler Stacks StackLang Part IX: Better Testing Today, we’ve got two main parts to work on: A new CLI New datatypes (VM only; so far!

Cleaner Lunar Arithmetic in Rust

2022-10-02

Another day, a slightly better way to implement Lunar Arithmetic in Rust. Give the previous post a read if you need a quick refresher on what Lunar integers are. Otherwise, here are two better (I hope) ways to solve the same problem.

Lunar Arithmetic in Rust

2022-09-21

I’ve been playing with various languages / language design a lot recently (inspired by my Runelang series). As I tweak and change what I’d like to implement in a language… I kept finding myself coming back to more or less exactly how Rust looks (albeit without the borrowing). So… that seems like a pretty good reason to start picking up some Rust. In another thread of thought, I stumbled upon two OEIS (on-line encyclopedia of integer sequences) sequences: A087061: Array T(n,k) = lunar sum n+k (n >= 0, k >= 0) read by antidiagonals and A087062: Array T(n,k) = lunar product n*k (n >= 1, k >= 1) read by antidiagonals.

AoC 2021 Day 25: Cucumbinator

2021-12-25

Source: Sea Cucumber

Part 1: Load a grid of empty cells (`.`), east movers (`>`), and south movers (`v`). Each step, move all east movers than all south movers (only if they can this iteration). Wrap east/west and north/south. How many steps does it take the movers to get stuck?

AoC 2021 Day 24: Aluinator

2021-12-24

Source: Arithmetic Logic Unit

Part 1: Simulate an ALU with 4 registers (`w`, `x`, `y`, and `z`) and instructions defined below. Find the largest 14 digit number with no 0 digits which result in `z=0`.

AoC 2021 Day 22: Cubinator

2021-12-22

Source: Reactor Reboot

Part 1: Given a series of 3D cubes that either turn ON all or turn OFF all points in their region, calculate how many points in the region (-50..50,-50..50,-50..50) are ON at the end.

AoC 2021 Day 19: Point Matchinator

2021-12-19

Source: Snailfish

Part 1: You will be given a series of Scanners, each of which will tell you the location (from their point of view) of a series of Beacons. Each Scanner may be flipped or rotated in increments of 90 degrees in any direction. Determine where each Scanner and Beacon is by overlaying the maps (with at least pairwise 12 matches).

AoC 2021 Day 11: Octopus Flashinator

2021-12-11

Source: Dumbo Octopus

Part 1: Simulate a grid of numbers such that on each tick: advance all numbers by 1, any number that increases over 9 will ‘flash’ and add 1 to all neighbors (recursively, but each cell can only flash once) and then reset to 0. Count the number of flashes in the first 100 ticks.

Source: Day 13: Claw Contraption

Part 1

Source: Day 7: Bridge Repair

Part 1

Source: Sea Cucumber

Part 1: Load a grid of empty cells (.), east movers (>), and south movers (v). Each step, move all east movers than all south movers (only if they can this iteration). Wrap east/west and north/south. How many steps does it take the movers to get stuck?

Source: Arithmetic Logic Unit

Part 1: Simulate an ALU with 4 registers (w, x, y, and z) and instructions defined below. Find the largest 14 digit number with no 0 digits which result in z=0.

Source: Reactor Reboot

Part 1: Given a series of 3D cubes that either turn ON all or turn OFF all points in their region, calculate how many points in the region (-50..50,-50..50,-50..50) are ON at the end.

Source: Snailfish

Source: Dumbo Octopus

Part 1: Simulate a grid of numbers such that on each tick: advance all numbers by 1, any number that increases over 9 will ‘flash’ and add 1 to all neighbors (recursively, but each cell can only flash once) and then reset to 0. Count the number of flashes in the first 100 ticks.

Part 1: Load a grid of empty cells (`.`), east movers (`>`), and south movers (`v`). Each step, move all east movers than all south movers (only if they can this iteration). Wrap east/west and north/south. How many steps does it take the movers to get stuck?

Part 1: Simulate an ALU with 4 registers (`w`, `x`, `y`, and `z`) and instructions defined below. Find the largest 14 digit number with no 0 digits which result in `z=0`.