AoC 2022 Day 24: Blizzinator

2022-12-24

Source: Blizzard Basin

Part 1

Given a map with a series of moving walls (that wrap when the hit the edges of the simulation), calculate the fastest route from the top left to the bottom right.

AoC 2022 Day 23: Elf Scattinator

2022-12-23

Source: Unstable Diffusion

Part 1

Implement a cellular automaton with the following rules:

If you have no neighbors, don’t move (important, I forgot this one for a while)
Otherwise:
- Calculate a potential move:
  - If you have no neighbors to the north, move north
  - If not, check likewise for south, then west, than east
- If no other agent is moving to the same space, move to your potential move
- Otherwise, don’t move
On each frame, rotate the order the directions are checked in (NSWE, SWEN, WENS, ENSW, NSWE, …)

AoC 2022 Day 22: Wonderator

2022-12-22

Source: Monkey Map

Part 1

Given a map and a series of instructions formatted as distance + turn (L or R), find the final position. Any time you would walk off the edge of the map, wrap to the opposite edge.

AoC 2022 Day 21: Yellinator

2022-12-21

Source: Monkey Math

Part 1

Given a series of equations of either the form dbpl: 5 or cczh: sllz + lgvd, determine what the value of the node labeled root is.

AoC 2022 Day 14: Sandinator

2022-12-14

Source: Regolith Reservoir

Part 1

Given a series of walls as input, run a falling sand simulation until any new sand falls of the map. Count how many grains of sand we end up with.

AoC 2022 Day 8: Treetopinator

2022-12-08

Source: Treetop Tree House

Part 1

Given a grid of numbers, count how many of these numbers have a direct path in any cardinal direction to the edge of the grid.

AoC 2017 Day 21: Fractal Expander

2017-12-21

Source: Fractal Art

Part 1: Start with an input image made of . and # pixels. For n iterations, break the image into blocks:
If the current size is even, break the image into 2x2 chunks and replace each with a 3x3 chunk
If the current size is odd, break the image into 3x3 chunks and replace each with a 4x4 chunk
The replacement rules will be specified in the following format (example is a 3x3 -> 4x4 rule):
.#./..#/### => #..#/..../..../#..#  
In that example, replace this:
.#.
..#
###
With this:
#..#
....
....
#..#
Any rotation or reflection of a chunk can be used to match the input of a replacement rule.
After n = 18 iterations, how many # pixels are there?

AoC 2017 Day 20: Miniature Universe Simulator

2017-12-20

Source: Particle Swarm

Part 1: Given the initial position, velocity, and acceleration of a large number of particles, which particle will stay the closet to the origin as the simulation runs to infinity?

AoC 2017 Day 18: Duetvm

2017-12-18

Source: Duet

Part 1: Create a virtual machine with the following instruction set:

snd X plays a sound with a frequency equal to the value of X
set X Y sets register X to Y
add X Y set register X to X + Y
mul X Y sets register X to X * Y
mod X Y sets register X to X mod Y
rcv X recovers the frequency of the last sound played, if X is not zero
jgz X Y jumps with an offset of the value of Y, iff X is greater than zero

In most cases, X and Y can be either an integer value or a register.

What is the value recovered by rcv the first time X is non-zero?

AoC 2017 Day 14: Knot Hash Gridinator

2017-12-14

Source: Disk Defragmentation

Part 1: Create a 128x128 grid. Generate each row by taking the knot hash of salt-{index}. The bits of the hash represent if a tile in the grid is free (0) or used (1).

Given your salt as input, how many squares are used?