Aurélien Geron
33 lines
732 B
Elixir
33 lines
732 B
Elixir
defmodule Aoc2024.Day02 do
|
|
def parse(input) do
|
|
Aoc2024.Utils.parse_rows_of_integers(input)
|
|
end
|
|
|
|
def part1(reports) do
|
|
reports |> Enum.count(&isValid/1)
|
|
end
|
|
|
|
defp isValid(report) do
|
|
diffs =
|
|
report
|
|
|> Enum.zip(tl(report))
|
|
|> Enum.map(fn {a, b} -> b - a end)
|
|
|
|
diffs |> Enum.all?(fn diff -> diff in [1, 2, 3] end) ||
|
|
diffs |> Enum.all?(fn diff -> diff in [-1, -2, -3] end)
|
|
end
|
|
|
|
def part2(reports) do
|
|
reports |> Enum.count(&isValidWithProblemDampener/1)
|
|
end
|
|
|
|
defp isValidWithProblemDampener(report) do
|
|
isValid(report) ||
|
|
report
|
|
|> Enum.with_index()
|
|
|> Enum.any?(fn {_elem, index} ->
|
|
isValid(report |> List.delete_at(index))
|
|
end)
|
|
end
|
|
end
|