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"""Day 11."""
with open("input") as f:
CHART = tuple(tuple(x) for x in f.read().rstrip().split("\n"))
EMPTY = 'L'
OCCUPIED = '#'
FLOOR = '.'
MIN = 0
MAX = len(CHART[0]) - 1
def clamp(num, minimium, maximium):
"""Clamp a number in between a range."""
if num <= minimium:
return minimium
if num >= maximium:
return maximium
return num
def get_neighbours(x, y):
"""Get neighbour cords for a point."""
pairs = set()
for i in range(x - 1, x + 2):
for j in range(y - 1, y + 2):
pairs.add(
(
clamp(i, MIN, MAX),
clamp(j, MIN, MAX)
)
)
# Remove self
pairs.remove((x, y))
return pairs
def get_new_seat(seat, neighbours, occupied_limit):
"""Get the new seat."""
occupied_sum = sum(1 if x == OCCUPIED else 0 for x in neighbours)
if seat == EMPTY and not any(x == OCCUPIED for x in neighbours):
return OCCUPIED
elif seat == OCCUPIED and occupied_sum >= occupied_limit:
return EMPTY
else:
return seat
def iterate_over_chart_part1(chart, p=False):
"""Iterate over a chart for part 1."""
new_map = []
for y, row in enumerate(chart):
new_map.append([])
for x, col in enumerate(row):
seat = chart[y][x]
neighbours = tuple(chart[pair[1]][pair[0]] for pair in get_neighbours(x, y))
new_map[y].append(get_new_seat(seat, neighbours, 4))
return new_map
def iterate_over_chart_part2(chart, p=False):
"""Iterate over a chart for part 2."""
new_map = []
for y, row in enumerate(chart):
new_map.append([])
for x, col in enumerate(row):
seat = chart[y][x]
neighbours = find_first_seat(x, y, chart)
new_map[y].append(get_new_seat(seat, neighbours, 5))
return new_map
def print_chart(chart):
"""Pretty print a chart."""
for y in chart:
line = ""
for x in y:
line += x
print(line)
def are_equal(chart1, chart2):
"""Check if two charts are equal."""
for idx, _ in enumerate(chart1):
if chart1[idx] != chart2[idx]:
return False
return True
def count_occupied(chart):
"""Count occupied seats in a chart."""
count = 0
for row in chart:
for x in row:
if x == OCCUPIED:
count += 1
return count
# Part 1
initial = CHART
count = 0
while True:
new_chart = iterate_over_chart_part1(initial)
if are_equal(new_chart, initial):
print(count_occupied(new_chart))
print("done")
break
else:
# print_chart(new_chart)
print(count)
count += 1
initial = new_chart
def find_first_seat(x, y, chart):
"""Find the first seat."""
seen_seats = []
# print("top")
for new_y in range(y - 1, MIN - 1, -1):
seat = chart[new_y][x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("top right")
for idx, new_y in enumerate(range(y - 1, MIN - 1, -1)):
new_x = x + idx + 1
if new_x > MAX:
break
seat = chart[new_y][new_x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("right")
for idx in range(len(chart[y][x:]) - 1):
new_x = x + idx + 1
seat = chart[y][new_x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("down right")
for idx, new_x in enumerate(range(x + 1, MAX + 1)):
new_y = y + idx + 1
if new_y > MAX:
break
seat = chart[new_y][new_x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("down")
for new_y in range(y + 1, MAX + 1):
seat = chart[new_y][x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("down left")
for idx, new_x in enumerate(range(x - 1, MIN - 1, -1)):
new_y = y + idx + 1
if new_y > MAX:
break
seat = chart[new_y][new_x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("left")
for idx in range(len(chart[y][:x + 1]) - 1):
new_x = x - idx - 1
seat = chart[y][new_x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
# print("top left")
for idx, new_x in enumerate(range(x - 1, MIN - 1, -1)):
new_y = y - idx - 1
if new_y < MIN:
break
seat = chart[new_y][new_x]
if seat in [OCCUPIED, EMPTY]:
seen_seats.append(seat)
break
return seen_seats
# Part 2
initial = CHART
count = 0
while True:
new_chart = iterate_over_chart_part2(initial)
if are_equal(new_chart, initial):
print(count_occupied(new_chart))
print("done")
break
else:
# print_chart(new_chart)
print(count)
count += 1
initial = new_chart
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