Jake Pullen
130 lines
4.1 KiB
Python
130 lines
4.1 KiB
Python
from copy import deepcopy
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with open(r'advent_of_code\2023\22\input.txt', 'r') as file:
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input = file.read()
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test_input = '''1,0,1~1,2,1
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0,0,2~2,0,2
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0,2,3~2,2,3
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0,0,4~0,2,4
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2,0,5~2,2,5
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0,1,6~2,1,6
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1,1,8~1,1,9'''
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def parse_input(input_data):
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# Split the input data into lines
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lines = input_data.split('\n')
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# Initialize the list of bricks
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bricks = []
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# Parse each line into a brick
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for line in lines:
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start, end = line.split('~')
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start_x, start_y, start_z = map(int, start.split(','))
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end_x, end_y, end_z = map(int, end.split(','))
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# Initialize the current brick
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current_brick = []
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# Add all points in the brick to the current brick
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if start_x == end_x and start_y == end_y:
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assert start_z <= end_z
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for z in range(start_z, end_z + 1):
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current_brick.append((start_x, start_y, z))
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elif start_x == end_x and start_z == end_z:
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assert start_y <= end_y
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for y in range(start_y, end_y + 1):
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current_brick.append((start_x, y, start_z))
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elif start_y == end_y and start_z == end_z:
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assert start_x <= end_x
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for x in range(start_x, end_x + 1):
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current_brick.append((x, start_y, start_z))
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else:
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assert False
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# Add the current brick to the list of bricks
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bricks.append(current_brick)
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return bricks
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def move_bricks_down(bricks):
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# Initialize the set of seen points
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seen_points = set()
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# Add all points in the bricks to the set of seen points
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for brick in bricks:
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for point in brick:
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seen_points.add(point)
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# Move all bricks down until they can't move anymore
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while True:
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moved = False
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for i, brick in enumerate(bricks):
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can_move = True
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for x, y, z in brick:
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if z == 1 or ((x, y, z - 1) in seen_points and (x, y, z - 1) not in brick):
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can_move = False
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if can_move:
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moved = True
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for point in brick:
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seen_points.discard(point)
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seen_points.add((point[0], point[1], point[2] - 1))
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bricks[i] = [(x, y, z - 1) for x, y, z in brick]
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if not moved:
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break
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return bricks, seen_points
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def count_stable_bricks(bricks, seen_points):
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# Initialize the counts of stable bricks and fallen bricks
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stable_bricks_count = 0
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# Check each brick
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for i, brick in enumerate(bricks):
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# Make a copy of the seen points and bricks
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current_seen_points = deepcopy(seen_points)
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current_bricks = deepcopy(bricks)
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# Remove the current brick from the seen points
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for point in brick:
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current_seen_points.discard(point)
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# Initialize the set of fallen bricks
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fallen_bricks = set()
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# Move all other bricks down until they can't move anymore
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while True:
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moved = False
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for j, other_brick in enumerate(current_bricks):
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if j == i:
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continue
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can_move = True
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for x, y, z in other_brick:
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if z == 1 or ((x, y, z - 1) in current_seen_points and (x, y, z - 1) not in other_brick):
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can_move = False
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if can_move:
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fallen_bricks.add(j)
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for point in other_brick:
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current_seen_points.discard(point)
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current_seen_points.add((point[0], point[1], point[2] - 1))
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current_bricks[j] = [(x, y, z - 1) for x, y, z in other_brick]
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moved = True
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if not moved:
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break
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# Update the counts of stable bricks and fallen bricks
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if len(fallen_bricks) == 0:
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stable_bricks_count += 1
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return stable_bricks_count
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def main():
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input_data = input
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bricks = parse_input(input_data)
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bricks, seen_points = move_bricks_down(bricks)
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stable_bricks_count = count_stable_bricks(bricks, seen_points)
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print(stable_bricks_count)
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main() |