1
0
advent-of-code-2k23/day3/day3.py
2023-12-03 23:14:42 +01:00

113 lines
3.6 KiB
Python

from typing import Tuple, List, Dict, Set
from dataclasses import dataclass
from collections import defaultdict
@dataclass(frozen=True)
class Item:
pos: Tuple[int, int]
symbol: str
def browse_schema(schema):
total_parts = 0
buf = []
max_row, max_col = len(schema), len(schema[0])
numbers: List[Item] = []
for y in range(max_row):
for x in range(max_col):
item = schema[y][x]
if item.isnumeric():
# continue parsing full number
buf.append(item)
elif buf:
# end of a number, do the engine part check
number = "".join(buf)
neighbors = get_neighbors((x, y), len(buf), schema)
start_pos = (x-len(number), y)
numbers.append(Item(start_pos, number))
if is_engine_part(neighbors):
total_parts += int(number)
buf.clear() # reached end of a number, clear buffer
print(f"Part 1, sum of the parts numbers = {total_parts}")
gears: Dict[Tuple[int, int], Set[Item]] = defaultdict(set)
for y in range(max_row):
for x in range(max_col):
item = schema[y][x]
if item == "*":
print(f"* ({x}, {y})")
neighbors = [n for n in get_neighbors_of((x, y), schema) if n.symbol.isdigit()]
if (x, y) == (5, 8):
breakpoint()
for neighbor in neighbors:
neighboring_numbers = [n for n in numbers
if y-1 <= n.pos[1] == y+1
and n.pos[0] <= neighbor.pos[0] <= n.pos[0] + len(n.symbol)]
gears[(x,y)] = gears[(x,y)].union(neighboring_numbers)
# gears = { key: value for key, value in gears.items() if len(value) <= 2 }
print(f"Part 2, sum of the gear ratios = TODO")
def is_engine_part(neighbors: List[Item]) -> bool:
# get list of symbols (not '.', \n or a number)
symbols = filter(lambda x: not x.symbol.isnumeric() and not x.symbol in (".", "\n"), neighbors)
return next(symbols, None) is not None
def get_neighbors(pos: Tuple[int, int], length: int, schema: List[List[str]]) -> List[Item]:
x, y = pos
start_x = x - length
neighbors = [get_neighbors_of((x, y), schema) for x in range(start_x, x)]
neighbors = [item for sublist in neighbors for item in sublist] # flatten list of list
return neighbors
def get_neighbors_of(pos: Tuple[int, int], schema: List[List[str]]) -> List[Item]:
max_row, max_col = len(schema), len(schema[0])
x, y = pos
neighbors: List[Item] = []
# top
if y-1 >= 0:
neighbors.append(Item((x, y-1), schema[y-1][x]))
# bottom:
if y+1 < max_row:
neighbors.append(Item((x, y+1), schema[y+1][x]))
# left
if x-1 >= 0:
neighbors.append(Item((x-1, y), schema[y][x-1]))
# right
if x+1 < max_col:
neighbors.append(Item((x+1, y), schema[y][x+1]))
# top-left
if y-1 >= 0 and x-1 >= 0:
neighbors.append(Item((x-1, y-1), schema[y-1][x-1]))
# top-right
if y-1 >= 0 and x+1 < max_col:
neighbors.append(Item((x+1, y-1), schema[y-1][x+1]))
# bottom-left
if y+1 < max_row and x-1 >= 0:
neighbors.append(Item((x-1, y+1), schema[y+1][x-1]))
# bottom-right
if y+1 < max_row and x+1 < max_col:
neighbors.append(Item((x+1, y+1), schema[y+1][x+1]))
return neighbors
if __name__ == "__main__":
import sys
infile = sys.argv[1]
with open(infile) as f:
schema = [[c for c in line] for line in f.readlines()]
browse_schema(schema)