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@ -4,9 +4,18 @@ |
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solve(InputData) -> |
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Rucksacks = binary:split(InputData, <<$\n>>, [trim_all, global]), |
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{lists:foldl(fun asdf/2, 0, Rucksacks), none}. |
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{lists:foldl(fun part1/2, 0, Rucksacks), part2(Rucksacks)}. |
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asdf(Rucksack, TotalPriority) -> |
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part2([]) -> 0; |
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part2([Ruck1, Ruck2, Ruck3 | Rest]) -> |
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[Badge] = maps:keys( |
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sets:intersection( |
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sets:intersection(tally(Ruck1), tally(Ruck2)), |
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tally(Ruck3) |
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)), |
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priority(Badge) + part2(Rest). |
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part1(Rucksack, TotalPriority) -> |
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CompartmentSize = byte_size(Rucksack) div 2, |
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<<Compartment1:CompartmentSize/binary, Compartment2:CompartmentSize/binary>> = Rucksack, |
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[DupeLetter] = maps:keys(sets:intersection(tally(Compartment1), tally(Compartment2))), |
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