Implement 2024 day 15

This commit is contained in:
2024-12-15 14:05:31 +01:00
parent 98983f622c
commit e90ee40880
5 changed files with 234 additions and 0 deletions

167
2024/src/aoc/days/day15.py Normal file
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import itertools
import numpy
from . import SeparateRunner
def parse_input(data: str) -> tuple[numpy.array, str]:
grid, steps = data.split("\n\n")
grid_split = numpy.array([list(line) for line in grid.split("\n")])
steps = "".join(steps.split("\n"))
return grid_split, steps
class DayRunner(SeparateRunner):
@classmethod
def part1(cls, input: str) -> None:
grid, steps = parse_input(input)
y, x = numpy.where(grid == "@")
x, y = x[0], y[0]
for c in steps:
match c:
case "^":
dx, dy = 0, -1
case ">":
dx, dy = 1, 0
case "<":
dx, dy = -1, 0
case "v":
dx, dy = 0, 1
case other:
raise ValueError(f"Invalid movement: {other}")
match grid[y + dy, x + dx]:
case "#":
continue
case "O":
crashed = False
for dist in itertools.count(2):
match grid[y + dist * dy, x + dist * dx]:
case "O":
continue
case "#":
crashed = True
break
case _:
crashed = False
break
if crashed:
continue
grid[y + dist * dy, x + dist * dx] = "O"
case _:
pass
grid[y, x] = "."
x += dx
y += dy
grid[y, x] = "@"
stones = numpy.where(grid == "O")
return sum(100 * y + x for y, x in zip(*stones))
@classmethod
def part2(cls, input: str) -> None:
input = input.replace(".", "..")
input = input.replace("#", "##")
input = input.replace("O", "[]")
input = input.replace("@", "@.")
grid, steps = parse_input(input)
y, x = numpy.where(grid == "@")
x, y = x[0], y[0]
for c in steps:
match c:
case "^":
dx, dy = 0, -1
case ">":
dx, dy = 1, 0
case "<":
dx, dy = -1, 0
case "v":
dx, dy = 0, 1
case other:
raise ValueError(f"Invalid movement: {other}")
match grid[y + dy, x + dx]:
case "#":
continue
case "]" | "[":
crashed = False
if dy == 0:
# easy case: just move linearly
for dist in itertools.count(2):
match grid[y, x + dist * dx]:
case "[" | "]":
continue
case "#":
crashed = True
break
case _:
break
if crashed:
continue
# shuffle all grid points one over
for steps in range(dist, 1, -1):
grid[y, x + dx * steps] = grid[y, x + dx * (steps - 1)]
else:
if grid[y + dy, x] == "[":
to_check = {x, x + 1}
else:
to_check = {x, x - 1}
moving_stones = [to_check]
for dist in itertools.count(2):
to_check_next = set()
for cx in to_check:
match grid[y + dist * dy, cx]:
case "#":
crashed = True
break
case "[":
to_check_next.add(cx)
to_check_next.add(cx + 1)
case "]":
to_check_next.add(cx)
to_check_next.add(cx - 1)
case _:
continue
if crashed or not to_check_next:
break
moving_stones.append(to_check_next)
to_check = to_check_next
if crashed:
continue
for steps in range(len(moving_stones), 0, -1):
dist = steps + 1
for cx in moving_stones[steps - 1]:
grid[y + dy * dist, cx] = grid[y + dy * (dist - 1), cx]
grid[y + dy * (dist - 1), cx] = "."
case _:
pass
grid[y, x] = "."
x += dx
y += dy
grid[y, x] = "@"
stones = numpy.where(grid == "[")
return sum(100 * y + x for y, x in zip(*stones))

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##########
#..O..O.O#
#......O.#
#.OO..O.O#
#..O@..O.#
#O#..O...#
#O..O..O.#
#.OO.O.OO#
#....O...#
##########
<vv>^<v^>v>^vv^v>v<>v^v<v<^vv<<<^><<><>>v<vvv<>^v^>^<<<><<v<<<v^vv^v>^
vvv<<^>^v^^><<>>><>^<<><^vv^^<>vvv<>><^^v>^>vv<>v<<<<v<^v>^<^^>>>^<v<v
><>vv>v^v^<>><>>>><^^>vv>v<^^^>>v^v^<^^>v^^>v^<^v>v<>>v^v^<v>v^^<^^vv<
<<v<^>>^^^^>>>v^<>vvv^><v<<<>^^^vv^<vvv>^>v<^^^^v<>^>vvvv><>>v^<<^^^^^
^><^><>>><>^^<<^^v>>><^<v>^<vv>>v>>>^v><>^v><<<<v>>v<v<v>vvv>^<><<>^><
^>><>^v<><^vvv<^^<><v<<<<<><^v<<<><<<^^<v<^^^><^>>^<v^><<<^>>^v<v^v<v^
>^>>^v>vv>^<<^v<>><<><<v<<v><>v<^vv<<<>^^v^>^^>>><<^v>>v^v><^^>>^<>vv^
<><^^>^^^<><vvvvv^v<v<<>^v<v>v<<^><<><<><<<^^<<<^<<>><<><^^^>^^<>^>v<>
^^>vv<^v^v<vv>^<><v<^v>^^^>>>^^vvv^>vvv<>>>^<^>>>>>^<<^v>^vvv<>^<><<v>
v^^>>><<^^<>>^v^<v^vv<>v^<<>^<^v^v><^<<<><<^<v><v<>vv>>v><v^<vv<>v^<<^

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########
#..O.O.#
##@.O..#
#...O..#
#.#.O..#
#...O..#
#......#
########
<^^>>>vv<v>>v<<

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#######
#...#.#
#.....#
#..OO@#
#..O..#
#.....#
#######
<vv<<^^<<^^

27
2024/tests/test_day15.py Normal file
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import pytest
from aoc.days.day15 import DayRunner
from . import get_data
@pytest.mark.parametrize(
"data,result",
[
(get_data(15, 1), 10092),
(get_data(15, 2), 2028),
],
)
def test_sample_part1(data: str, result: int) -> None:
assert DayRunner.part1(data) == result
@pytest.mark.parametrize(
"data,result",
[
(get_data(15, 1), 9021),
(get_data(15, 3), 618),
],
)
def test_sample_part2(data: str, result: int) -> None:
assert DayRunner.part2(data) == result