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|
defmodule Solver do
def to_interval(range) do
[left, right] = String.split(range, "-")
{left, ""} = Integer.parse(left)
{right, ""} = Integer.parse(right)
{left, right}
end
def contained({a0, a1}, {b0, b1}) do
(a0 - b0) * (a1 - b1) <= 0
end
def overlap({a0, a1}, {b0, b1}) do
a0 <= b1 && b0 <= a1
end
end
{:ok, input} = File.read("input")
parsed =
input
|> String.split("\n", trim: true)
|> Enum.map(&String.split(&1, ","))
|> Enum.map(fn [left, right] -> {Solver.to_interval(left), Solver.to_interval(right)} end)
parsed
|> Enum.map(fn {left, right} -> Solver.contained(left, right) end)
|> Enum.filter(& &1)
|> length
|> IO.puts()
parsed
|> Enum.map(fn {left, right} -> Solver.overlap(left, right) end)
|> Enum.filter(& &1)
|> length
|> IO.puts()
|
