# Day 7
```elixir
Mix.install([
{:kino, "~> 0.8.0"}
])
```
## Part 1
```elixir
test_input = """
$ cd /
$ ls
dir a
14848514 b.txt
8504156 c.dat
dir d
$ cd a
$ ls
dir e
29116 f
2557 g
62596 h.lst
$ cd e
$ ls
584 i
$ cd ..
$ cd ..
$ cd d
$ ls
4060174 j
8033020 d.log
5626152 d.ext
7214296 k
$ cd ..
$ cd p
$ cd q
$ cd p
500001 file.txt
"""
```
```elixir
defmodule Day7 do
def part1(input) do
input
|> traverse()
|> Enum.filter(fn {_, v} ->
is_integer(v) and v < 100_000
end)
|> Keyword.values()
|> Enum.sum()
end
@needed 70_000_000 - 30_000_000
def part2(input) do
result = input |> traverse()
result
|> Enum.filter(fn {_, v} ->
is_integer(v) and v > result["/"] - @needed
end)
|> Keyword.values()
|> Enum.sort()
|> hd()
end
def traverse(input) do
input
|> String.split("\n", trim: true)
|> Enum.reduce(%{current_dir: [], files: %{}}, fn x, state ->
parse_command(x, state)
end)
end
def parse_command("$ cd /", state) do
Map.put(state, :current_dir, ["/"])
end
def parse_command("$ cd ..", state) do
[_ | rest] = Map.get(state, :current_dir, [])
Map.put(state, :current_dir, rest)
end
def parse_command("$ cd " <> dir, state) do
[h | _] = l = Map.get(state, :current_dir, [])
new_path = h <> "/" <> dir
Map.put(state, :current_dir, [new_path | l])
end
def parse_command("$ ls" <> _, y), do: y
def parse_command("dir " <> _, y), do: y
def parse_command(x, y) do
[size, _] = String.split(x)
y.current_dir
|> Enum.reduce(y, fn current_dir, acc ->
Map.update(acc, current_dir, String.to_integer(size), &(&1 + String.to_integer(size)))
end)
end
end
path = "Projects/aoc/2022/day7.txt"
input = File.read!(path)
IO.inspect(Day7.part1(input))
Day7.part2(input)
```
