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|
reindeer =
File.stream!("inputs/day14.txt")
|> Enum.map(fn line ->
[speed, stamina, recovery] =
Regex.run(
~r/\w+ can fly (\d+) km\/s for (\d+) seconds, but then must rest for (\d+) seconds./,
line
)
|> Stream.drop(1)
|> Stream.map(&Integer.parse/1)
|> Enum.map(fn {i, _} -> i end)
{speed, stamina, recovery}
end)
totalRaceLength = 2503
distancesAfterRaceLength = fn raceLength ->
Enum.map(reindeer, fn {speed, stamina, recovery} ->
fullIterationDuration = stamina + recovery
fullIterationCount = div(raceLength, fullIterationDuration)
lastIterationDuration = rem(raceLength, fullIterationDuration)
lastIterationRuntime = min(stamina, lastIterationDuration)
runtime = fullIterationCount * stamina + lastIterationRuntime
runtime * speed
end)
end
maxDistance = distancesAfterRaceLength.(totalRaceLength) |> Enum.max()
IO.puts("Max distance: #{maxDistance}")
maxPoints =
Enum.map(1..totalRaceLength, fn raceLength ->
distances = distancesAfterRaceLength.(raceLength)
maxDistance = Enum.max(distances)
Enum.map(distances, fn
^maxDistance -> 1
_ -> 0
end)
end)
|> List.zip()
|> Enum.map(&Tuple.to_list/1)
|> Enum.map(&Enum.sum/1)
|> Enum.max()
IO.puts("Max points: #{maxPoints}")
|
