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#!/usr/bin/env python3
import itertools
def solve(nums: list[str]) -> int:
nummap: dict[str, set[str]] = {}
# First pass, find the easy patterns. From these 4 patterns you can determine all other ones
for n in nums:
nummap[[0, 0, 1, 7, 4, 0, 0, 8][len(n)]] = set(n)
# Second pass, here we use the magic of sets to work out all the other numbers from the 4
# that we found above
for n in nums:
match len((s := set(n))):
# 2, 3, or 5
case 5:
# 1 is a subset of 3 and none of the others
if nummap[1].issubset(s):
nummap[3] = s
# 4 is a subset of 5 union with 1 but not 2 union with 1
elif nummap[4].issubset(s.union(nummap[1])):
nummap[5] = s
else:
nummap[2] = s
# 0, 6, or 9
case 6:
# 1 is a subset of 6 but not 0 or 9
if not nummap[1].issubset(s):
nummap[6] = s
# 4 is a subset of 9 but not 0
elif nummap[4].issubset(s):
nummap[9] = s
else:
nummap[0] = s
nums = nums[nums.index("|") + 1 :]
acc = 0
for n, (k, v) in itertools.product(nums, nummap.items()):
if set(n) == v:
acc = acc * 10 + k
return acc
def main() -> None:
with open("input", "r", encoding="utf-8") as f:
data = list(map(lambda l: l.strip().split(), f.readlines()))
print(sum(solve(line) for line in data))
if __name__ == "__main__":
main()
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