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contents = File.read!("inputs/day3.txt")
directions = String.codepoints(contents)
move = fn
"^", {x, y} -> {x, y - 1}
"<", {x, y} -> {x - 1, y}
">", {x, y} -> {x + 1, y}
"v", {x, y} -> {x, y + 1}
end
coordinates = Enum.scan(directions, {0, 0}, move)
unique_coordinates = Enum.uniq(coordinates)
IO.puts("Unique Households for Just Santa: #{length(unique_coordinates)}")
get_shared_coords = fn offset ->
Enum.with_index(directions)
|> Enum.filter(fn {_, i} -> rem(i, 2) == offset end)
|> Enum.map(fn {val, _} -> val end)
|> Enum.scan({0, 0}, move)
end
regular_santa_coordinates = get_shared_coords.(0)
robo_santa_coordinates = get_shared_coords.(1)
shared_coordinates = regular_santa_coordinates ++ robo_santa_coordinates
unique_shared_coordinates = Enum.uniq(shared_coordinates)
IO.puts("Unique Households for Santa and RoboSanta: #{length(unique_shared_coordinates)}")
|
