From c3acb83111f98247f7d3a1ae74db3fe8c67f19b6 Mon Sep 17 00:00:00 2001
From: Petros Amoiridis <petros@hey.com>
Date: Fri, 6 Dec 2024 23:02:23 +0200
Subject: [PATCH] Solve day 3 part 2

---
 lib/day03/solution.ex | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/lib/day03/solution.ex b/lib/day03/solution.ex
index e178a6a..66588c9 100644
--- a/lib/day03/solution.ex
+++ b/lib/day03/solution.ex
@@ -15,4 +15,29 @@ defmodule Aoc2024.Day03.Solution do
     |> Enum.map(fn x -> Enum.product(x) end)
     |> Enum.sum()
   end
+
+  @doc """
+  # Examples
+      iex> Aoc2024.Day03.Solution.split_parts("xmul(2,4)&mul[3,7]!^don't()_mul(5,5)+mul(32,64](mul(11,8)undo()?mul(8,5))")
+      ["xmul(2,4)&mul[3,7]!^", "don't", "()_mul(5,5)+mul(32,64](mul(11,8)un", "do", "()?mul(8,5))"]
+  """
+  def split_parts(memory) do
+    Regex.split(~r/don't|do/, memory, include_captures: true, trim: true)
+  end
+
+  @doc """
+  # Examples
+      iex> Aoc2024.Day03.Solution.solve_part2("xmul(2,4)&mul[3,7]!^don't()_mul(5,5)+mul(32,64](mul(11,8)undo()?mul(8,5))")
+      48
+  """
+  def solve_part2(memory) do
+    "do#{memory}"
+    |> Aoc2024.Day03.Solution.split_parts()
+    |> Enum.chunk_every(2)
+    |> Enum.reject(fn x -> List.first(x) == "don't" end)
+    |> List.flatten()
+    |> Enum.reject(fn x -> x == "do" end)
+    |> List.to_string()
+    |> Aoc2024.Day03.Solution.solve_part1()
+  end
 end