Add Day 2 Part 2

Author: Linuus

lib/advent_of_code.ex

@@ -8,5 +8,6 @@ defmodule AdventOfCode do
   def day02 do
     IO.puts "-- Day 02 --"
     AdventOfCode.Day02.Part01.run()
+    AdventOfCode.Day02.Part02.run()
   end
 end

lib/day02/part02.ex

@@ -0,0 +1,30 @@
+defmodule AdventOfCode.Day02.Part02 do
+  def run do
+    IO.puts "Part 2: #{solve()}"
+  end
+
+  defp solve do
+    input()
+    |> Enum.map(&diffs/1)
+    |> List.flatten()
+    |> Enum.sum()
+  end
+
+  defp diffs(str) do
+    str
+    |> String.split("\t")
+    |> Enum.map(&to_integer/1)
+    |> find_even_divide()
+  end
+
+  defp find_even_divide(list) do
+    for x <- list, y <- list, x != y, rem(x, y) == 0, do: div(x, y)
+  end
+
+  defp to_integer(str) do
+    {int, _} = Integer.parse(str)
+    int
+  end
+
+  defp input, do: File.stream!("lib/inputs/day2_0.txt")
+end