Wasn't doing AOC this year, but did this day specifically for some friends. Hacked together and written without execution speed in mind - instead, I wanted to get working code as quickly as possible.
@skifli ➜ /workspaces/bruty (main) $ time python day_06.py
Part 1: 4656
Part 2: 1575
real 0m5.520s
user 0m5.369s
sys 0m0.017s
| import functools | |
| import itertools | |
| import os | |
| import typing | |
| def get_new_coords(guard: dict, inp_map: list) -> typing.Optional[tuple]: | |
| dx, dy = DIRECTIONS[guard["dir"]]["x"], DIRECTIONS[guard["dir"]]["y"] | |
| new_x, new_y = guard["x"] + dx, guard["y"] + dy | |
| if 0 <= new_x < COL_COUNT and 0 <= new_y < ROW_COUNT: | |
| return new_x, new_y | |
| return None # Out of bounds | |
| @functools.lru_cache | |
| def rotate_direction(current_dir: str) -> str: | |
| return POSSIBLE_DIRECTIONS[(POSSIBLE_DIRECTIONS.index(current_dir) + 1) % POSSIBLE_DIRECTIONS_LEN] | |
| def part1(inp_map: list, guard: dict) -> int: | |
| distinct_positions = {(guard["x"], guard["y"])} # Use tuple directly for coordinates | |
| guard = guard.copy() | |
| while True: | |
| new_coords = get_new_coords(guard, inp_map) | |
| if new_coords is None: # Out of bounds | |
| break | |
| x, y = new_coords | |
| if inp_map[y][x] == "#": | |
| guard["dir"] = rotate_direction(guard["dir"]) | |
| else: | |
| guard["x"], guard["y"] = x, y | |
| distinct_positions.add((x, y)) | |
| return distinct_positions | |
| def part2(obstacle_positions: set, inp_map: list, guard: dict) -> int: | |
| matches = 0 | |
| for x, y in obstacle_positions: | |
| if inp_map[y][x] not in DIRECTIONS and inp_map[y][x] != "#": | |
| # Modify map in-place for obstruction and restore after | |
| original_char = inp_map[y][x] | |
| inp_map[y][x] = "#" | |
| current_guard = { | |
| "x": guard["x"], | |
| "y": guard["y"], | |
| "dir": guard["dir"], | |
| } | |
| distinct_states = set() | |
| while True: | |
| new_coords = get_new_coords(current_guard, inp_map) | |
| if new_coords is None: # Out of bounds | |
| break | |
| cx, cy = new_coords | |
| if inp_map[cy][cx] == "#": | |
| current_guard["dir"] = rotate_direction(current_guard["dir"]) | |
| if (current_guard["x"], current_guard["y"], current_guard["dir"]) in distinct_states: | |
| matches += 1 | |
| break | |
| distinct_states.add((current_guard["x"], current_guard["y"], current_guard["dir"])) | |
| else: | |
| current_guard["x"], current_guard["y"] = cx, cy | |
| # Restore map to original state | |
| inp_map[y][x] = original_char | |
| return matches | |
| DIRECTIONS: typing.Final[dict] = { # Directions in order of rotation | |
| "^": {"x": 0, "y": -1}, | |
| ">": {"x": 1, "y": 0}, | |
| "v": {"x": 0, "y": 1}, | |
| "<": {"x": -1, "y": 0}, | |
| } | |
| POSSIBLE_DIRECTIONS = list(DIRECTIONS.keys()) | |
| POSSIBLE_DIRECTIONS_LEN = len(POSSIBLE_DIRECTIONS) | |
| path = os.path.split(__file__)[0] | |
| with open(f"{path}/input.txt", "r") as f: | |
| inp_raw = f.read() | |
| inp_map = [list(line) for line in inp_raw.split("\n")] | |
| guard = None | |
| ROW_COUNT = len(inp_map) | |
| COL_COUNT = len(inp_map[0]) | |
| for y, line in enumerate(inp_map): | |
| for x, char in enumerate(line): | |
| if char in DIRECTIONS: | |
| guard = {"x": x, "y": y, "dir": char} | |
| break | |
| part_1_data = part1(inp_map, guard) | |
| print(f"Part 1: {len(part_1_data)}") | |
| part_2_data = part2(part_1_data, inp_map, guard) | |
| print(f"Part 2: {part_2_data}") |