class Y2017D5(object):
def __init__(self, file_name):
self.input = Input(file_name).ints()
def part1(self):
result = 0
cpu_instructions = self.input.copy()
input_length = len(self.input)
pointer = 0
while 0 <= pointer < input_length:
value = cpu_instructions[pointer]
cpu_instructions[pointer] += 1
pointer += value
result += 1
print("Part 1:", result)
def part2(self):
result = 0
cpu_instructions = self.input.copy()
input_length = len(self.input)
pointer = 0
while 0 <= pointer < input_length:
value = cpu_instructions[pointer]
if value >= 3:
cpu_instructions[pointer] -= 1
else:
cpu_instructions[pointer] += 1
pointer += value
result += 1
print("Part 2:", result)
class Y2021D25(object):
def __init__(self, file_name):
self._grid = Input(file_name).grid()
def part1(self):
result = 0
grid = self._grid.copy()
while True:
result += 1
changed_east, grid = self._mutate(grid, Moving.EAST)
changed_south, grid = self._mutate(grid, Moving.SOUTH)
# grid.print()
# print()
if not changed_east and not changed_south:
break
print("Part 1:", result)
@staticmethod
def _mutate(grid: Grid[str], moving: Moving) -> (bool, Grid[str]):
result = grid.copy()
max_x = grid.max_x
max_y = grid.max_y
locations = grid.find('>') if moving == Moving.EAST else grid.find('v')
something_changed = False
for location in locations:
test = location.right(
) if moving == Moving.EAST else location.down()
if test.x > max_x:
test = Coordinate(0, test.y, system=test.system)
if test.y > max_y:
test = Coordinate(test.x, 0, system=test.system)
if grid[test] == '.':
result[test] = '>' if moving == Moving.EAST else 'v'
result[location] = '.'
something_changed = True
return something_changed, result
class Y2021D11(object):
def __init__(self, file_name):
self._grid = Input(file_name).grid().map(lambda x: int(x))
def part1(self):
result = 0
grid = self._grid.copy()
for _ in range(100):
result += self._step(grid)
print("Part 1:", result)
def part2(self):
grid = self._grid.copy()
step = 0
while True:
step += 1
flash_count = self._step(grid)
if flash_count == 100:
result = step
break
print("Part 2:", result)
@staticmethod
def _step(grid: InfiniteGrid[int]) -> int:
result = 0
for row in range(10):
for col in range(10):
grid[col, row] = grid[col, row] + 1
should_flash = grid.find(lambda value: value > 9)
already_flashed = set()
queue: Queue = Queue()
while should_flash:
queue.put(should_flash.pop())
while not queue.empty():
coordinate: Coordinate = queue.get()
if coordinate in already_flashed:
continue
already_flashed.add(coordinate)
grid[coordinate] = 0
result += 1
neighbors = coordinate.neighbors8()
for neighbor in neighbors:
if neighbor not in grid:
continue
if neighbor in already_flashed:
continue
grid[neighbor] += 1
if grid[neighbor] > 9:
queue.put(neighbor)
return result
class Y2018D18(object):
def __init__(self, file_name):
self.initial_grid = Input(file_name).grid()
def part1(self):
grid = self.initial_grid.copy()
for i in range(10):
grid = self._mutate(grid)
wooded = len(grid.find('|'))
lumberyards = len(grid.find('#'))
result = wooded * lumberyards
print("Part 1:", result)
def part2(self):
grid = self.initial_grid.copy()
grid_lookup = {}
minute_lookup = {}
my_hash = self._hash(grid)
minute = 0
while my_hash not in grid_lookup:
grid_lookup[my_hash] = grid
minute_lookup[my_hash] = minute
grid = self._mutate(grid)
my_hash = self._hash(grid)
minute += 1
wanted = 1000000000
remaining = (wanted - minute) % (minute - minute_lookup[my_hash])
for _ in range(remaining):
grid = self._mutate(grid)
wooded = len(grid.find('|'))
lumberyards = len(grid.find('#'))
result = wooded * lumberyards
print("Part 2:", result)
@staticmethod
def _hash(grid: Grid[str]):
coordinates = sorted(list(grid))
md5_func = hashlib.md5()
for coordinate in coordinates:
md5_func.update(str(coordinate).encode())
md5_func.update(grid[coordinate].encode())
return md5_func.hexdigest()
@staticmethod
def _mutate(grid: Grid[str]) -> Grid[str]:
result = Grid[str](grid.width, grid.height)
for coordinate, acre in grid.items():
tree_count = 0
lumberyard_count = 0
for neighbor in coordinate.neighbors8():
if grid[neighbor] == '|':
tree_count += 1
elif grid[neighbor] == '#':
lumberyard_count += 1
if acre == '.' and tree_count >= 3:
result[coordinate] = '|'
elif acre == '|' and lumberyard_count >= 3:
result[coordinate] = '#'
elif acre == '#' and (lumberyard_count < 1 or tree_count < 1):
result[coordinate] = '.'
else:
result[coordinate] = acre
return result
