Mikaël Capelle 87936d6422
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Refactor code for API (#3)
Co-authored-by: Mikael CAPELLE <mikael.capelle@thalesaleniaspace.com>
Co-authored-by: Mikaël Capelle <capelle.mikael@gmail.com>
Reviewed-on: #3
2024-12-08 13:06:41 +00:00

71 lines
1.9 KiB
Python

from typing import Any, Iterator, TypeAlias
from ..base import BaseSolver
RockGrid: TypeAlias = list[list[str]]
def slide_rocks_top(rocks: RockGrid) -> RockGrid:
top = [0 if c == "." else 1 for c in rocks[0]]
for row in range(1, len(rocks)):
for col in range(len(rocks[0])):
match rocks[row][col]:
case "O":
if top[col] != row:
rocks[top[col]][col] = "O"
rocks[row][col] = "."
top[col] = top[col] + 1
case "#":
top[col] = row + 1
case _:
pass
return rocks
def cycle(rocks: RockGrid) -> RockGrid:
for _ in range(4):
rocks = slide_rocks_top(rocks)
rocks = [
[rocks[len(rocks) - j - 1][i] for j in range(len(rocks))]
for i in range(len(rocks[0]))
]
return rocks
class Solver(BaseSolver):
def solve(self, input: str) -> Iterator[Any]:
rocks0 = [list(line) for line in input.splitlines()]
rocks = slide_rocks_top([[c for c in r] for r in rocks0])
# part 1
yield sum(
(len(rocks) - i) * sum(1 for c in row if c == "O")
for i, row in enumerate(rocks)
)
# part 2
rocks = rocks0
N = 1000000000
cycles: list[RockGrid] = []
i_cycle: int = -1
for i_cycle in range(N):
rocks = cycle(rocks)
if any(rocks == c for c in cycles):
break
cycles.append([[c for c in r] for r in rocks])
cycle_start = next(i for i in range(len(cycles)) if (rocks == cycles[i]))
cycle_length = i_cycle - cycle_start
ci = cycle_start + (N - cycle_start) % cycle_length - 1
yield sum(
(len(rocks) - i) * sum(1 for c in row if c == "O")
for i, row in enumerate(cycles[ci])
)