AdventOfCode/2020/elixir/day1/day1part2.exs

27 lines
551 B
Elixir

defmodule Day1Part2 do
def run do
{a, b, c} =
File.read!("input")
|> String.trim()
|> String.split("\n")
|> Enum.map(&String.to_integer/1)
|> find_2020()
IO.puts("#{a} x #{b} x #{c} = #{a * b * c}")
end
def find_2020([current | rest]) do
pair =
for i <- rest, j <- rest do
if current + i + j == 2020, do: {i, j}, else: nil
end
|> Enum.find(&match?({_, _}, &1))
case pair do
{a, b} -> {a, b, current}
nil -> find_2020(rest)
end
end
end
Day1Part2.run()