45 lines
1.5 KiB
Python
45 lines
1.5 KiB
Python
import re
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def parse(filename):
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bags = {}
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inverted_bags = {}
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with open(filename) as in_f:
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for line in in_f.readlines():
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color, _, rest = map(lambda s: s.strip(), line.partition("bags contain "))
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bags[color] = {}
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if not rest.startswith("no other"):
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parts = re.sub(r'bag[s\.]*', ' ', rest).split(",")
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parts = list(map(lambda s: s.strip().partition(" "), parts))
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for part in parts:
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ccolor, ccount = part[2], int(part[0])
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bags[color][ccolor] = ccount
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if ccolor in inverted_bags:
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inverted_bags[ccolor].add(color)
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else:
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inverted_bags[ccolor] = {color}
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return (bags, inverted_bags)
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def part1(inverted_bags, colors, found = set()):
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if len(colors) != 0:
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for color in colors:
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found = found.union(inverted_bags[color])
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inverted_bags.pop(color)
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colors = set(inverted_bags.keys()).intersection(found)
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return part1(inverted_bags, colors, found)
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return len(found)
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def part2(bags, color, current=1):
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el = bags[color]
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if len(el) != 0:
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return current + current * sum(part2(bags, key, el[key]) for key in el)
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else:
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return current
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(bags, inverted_bags) = parse("day7.input")
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print("part1 = {}".format(part1(inverted_bags, {"shiny gold"})))
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print("part2 = {}".format(part2(bags, "shiny gold") - 1))
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