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from functools import reduce
from utils import open_day, Point2D, adjacent_bounded
from collections import deque
heatmap = [[int(c) for c in l.rstrip()] for l in open_day(9)]
bounds = Point2D(len(heatmap[0]), len(heatmap))
adj = [(1, 0), (0, 1), (-1, 0), (0, -1)]
def is_low(p):
risk = heatmap[p.y][p.x]
for n in adjacent_bounded(p, bounds, False):
if heatmap[n.y][n.x] <= risk:
return False
return True
def basin_size(p):
seen = set()
queue = deque((p,))
size = 0
while queue:
p = queue.popleft()
if p in seen:
continue
seen.add(p)
if heatmap[p.y][p.x] == 9:
continue
size += 1
for n in adjacent_bounded(p, bounds, False):
# print(p, n)
queue.append(n)
return size
totrisk = 0
lows = []
for y in range(bounds.y):
for x in range(bounds.x):
p = Point2D(x, y)
if is_low(p):
totrisk += 1 + heatmap[y][x]
lows.append(basin_size(p))
print(totrisk)
lows.sort()
print(reduce(lambda x, y: x * y, lows[-3:], 1))
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