# Day 12
```elixir
Mix.install([
{:kino, "~> 0.6.2"}
])
```
## Input
```elixir
input = Kino.Input.textarea("In put here:")
```
<!-- livebook:{"reevaluate_automatically":true} -->
```elixir
map =
input
|> Kino.Input.read()
|> String.split("\n", strip: true)
|> Enum.map(&(String.split(&1, "-") |> List.to_tuple()))
defmodule Cave do
def neighbors(node, map) do
Enum.flat_map(map, fn
{^node, a} -> [a]
{a, ^node} -> [a]
{_, _} -> []
end)
end
def split(list) do
Enum.group_by(list, fn x ->
cond do
x == "start" -> :start
x == "end" -> :end
x == String.upcase(x) -> :big
x == String.downcase(x) -> :small
end
end)
end
def can_add?(x, path, maxcnt) do
caves = path |> split
if Map.has_key?(caves, :small) do
duplicate = Enum.frequencies([x | caves.small]) |> Enum.filter(&(elem(&1, 1) > 1))
case duplicate do
[] -> true
[{_, cnt}] -> cnt <= maxcnt
_ -> false
end
else
true
end
end
def search(map, maxcnt \\ 1), do: search(map, "start", ["start"], maxcnt)
def search(map, node, path, maxcnt) do
paths = neighbors(node, map) |> split
small_paths =
if Map.has_key?(paths, :small) do
Enum.flat_map(
paths.small
|> Enum.filter(fn x ->
can_add?(x, path, maxcnt)
end),
fn x ->
search(map, x, [x | path], maxcnt)
end
)
else
[]
end
large_paths =
if Map.has_key?(paths, :big) do
Enum.flat_map(
paths.big,
fn x ->
search(map, x, [x | path], maxcnt)
end
)
else
[]
end
if Map.has_key?(paths, :end) do
Enum.concat([[["end" | path]], small_paths, large_paths])
else
small_paths ++ large_paths
end
end
end
```
## Part 1
<!-- livebook:{"reevaluate_automatically":true} -->
```elixir
Cave.search(map) |> IO.inspect() |> Enum.count()
```
## Part 2
```elixir
Cave.search(map, 2) |> IO.inspect() |> Enum.count()
```
