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@justecorruptio
Last active December 15, 2022 20:36
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Advent of Code 2022 Day 15 Part2
from itertools import product
import re
fh = open('input', 'r')
lines = {}
for line in fh:
sx, sy, bx, by = map(int, re.findall('-?\d+', line))
d = abs(bx - sx) + abs(by - sy) + 1
for endpoints, mb, norm in [
((sx - d, sx), (-1, sy - d + sx), -1),
((sx, sx + d), ( 1, sy - d - sx), -1),
((sx, sx + d), (-1, sy + d + sx), 1),
((sx - d, sx), ( 1, sy + d - sx), 1),
]:
lines.setdefault(mb, {-1:[], 1:[]})[norm].append( endpoints )
slopes = {-1: [], 1:[]}
for (m, b), norms in lines.items():
for (x1, x2), (x3, x4) in product(*norms.values()):
o1, o2 = max(x1, x3), min(x2, x4)
if o1 <= o2:
slopes[m].append((b, (o1, o2)))
for (b1, (x1, x2)), (b2, (x3, x4)) in product(slopes[-1], slopes[1]):
x = (b2 - b1) // -2
y = x + b2
if x1 <= x <= x2 and x3 <= x <= x4:
print(x * 4000000 + y)
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