aoc2020/11/2.py

121 lines
2.7 KiB
Python

def first_of(haystack, needles):
element = len(haystack) - 1
for needle in needles:
if needle in haystack:
element = min(haystack.index(needle), element)
return haystack[element] if haystack else ""
def count_adjacent(grid, line, seat):
adjs = []
h = len(grid) - 1
w = len(grid[0]) - 1
# generate lists
#
# D1 V1 D2
# H1 XX H2
# D3 V2 D4
#
# vertical lists
v1 = []
if line > 0:
for x in range(line - 1, -1, -1):
v1.append(grid[x][seat])
v2 = []
if line < w:
for x in range(line + 1, len(grid)):
v2.append(grid[x][seat])
# horizontal lists
h1 = []
if seat > 0:
h1 = grid[line][seat - 1::-1]
h2 = grid[line][seat+1:]
# diagonal lists
d1 = []
s = seat - 1
l = line - 1
for __ in range(min(line, seat)):
d1.append(grid[l][s])
l -=1
s -=1
d2 = []
s = seat + 1
l = line - 1
for __ in range(min(line, w - seat)):
d2.append(grid[l][s])
l -=1
s +=1
d3 = []
s = seat - 1
l = line + 1
for __ in range(min(h - line, seat)):
d3.append(grid[l][s])
l +=1
s -=1
d4 = []
s = seat + 1
l = line + 1
for __ in range(min(h - line, w - seat)):
d4.append(grid[l][s])
l +=1
s +=1
adjs.append(first_of(v1, ["#", "L"]))
adjs.append(first_of(v2, ["#", "L"]))
adjs.append(first_of(h1, ["#", "L"]))
adjs.append(first_of(h2, ["#", "L"]))
adjs.append(first_of(d1, ["#", "L"]))
adjs.append(first_of(d2, ["#", "L"]))
adjs.append(first_of(d3, ["#", "L"]))
adjs.append(first_of(d4, ["#", "L"]))
return adjs.count("#")
with open("input") as f:
content = [[y for y in x.strip()] for x in f]
new = last = content
changes = 1
#for line in content:
# print("".join(line))
iterations = 0
while changes > 0:
iterations += 1
# print(".", end="", flush=True)
last = []
for line in new:
last.append(line.copy())
changes = 0
for line in range(len(last)):
adjs = []
for seat in range(len(last[line])):
status = last[line][seat]
adj = count_adjacent(last, line, seat)
adjs.append(str(adj))
if status == "L" and adj == 0:
new[line][seat] = "#"
changes += 1
elif status == "#" and adj >= 5:
new[line][seat] = "L"
changes += 1
# print("".join(adjs), "".join(new[line]))
# for line in new:
# print("".join(line))
#for line in new:
# print("".join(line))
count = 0
for line in last:
count += line.count("#")
print(count)