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# Advent of Code 2022 - Day 1
## Puzzle description
[Day 1: Calorie Counting](https://adventofcode.com/2022/day/1).
## Input
```elixir
defmodule Input do
def load! do
"input/01.txt"
|> Path.expand(__DIR__)
|> File.stream!()
end
@doc """
Returns normalized output when generating streams from files or string input.
"""
def to_stream(input) when is_binary(input) do
input
|> String.trim("\n")
|> String.splitter("\n")
end
def to_stream(stream) do
stream
|> Stream.map(fn string -> String.trim_trailing(string, "\n") end)
end
end
```
## Solution
```elixir
defmodule Part1 do
# preflight:
## split string into lines (without break characters)
def run(input) do
# 1) transform input to grouped totals
# 2) return the max of the totals
input
|> to_grouped_sums()
|> Enum.max()
end
def to_grouped_sums(input) do
input
|> Stream.transform(
fn -> [] end,
fn
## if the item is the empty string (""), then:
### add the accumulated items to the new stream
### reset the accumulator to the empty list
"", acc ->
{[acc], []}
item, acc ->
## otherwise, add the item to the head of the accumulator
{[], [String.to_integer(item) | acc]}
end,
fn
[] -> {:halt, []}
acc -> {[acc], []}
end,
fn _ -> :ok end
)
|> Stream.map(&Enum.sum/1)
end
end
defmodule Part2 do
# preflight:
## split string into lines (without break characters)
def run(input) do
# 1) transform input to grouped totals
# 2) sort totals descending (sort + reverse)
# 3) take the top 3 totals
# 4) return the sum of the top 3 totals
input
|> Part1.to_grouped_sums()
|> Enum.into([])
|> Enum.sort()
|> Enum.reverse()
|> Enum.take(3)
|> Enum.sum()
end
end
ExUnit.start(autorun: false)
defmodule Test do
use ExUnit.Case, async: true
@example_input ~s(
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
)
@input Input.load!()
test "part 1" do
assert @example_input |> Input.to_stream() |> Part1.run() === 24000
@input |> Input.to_stream() |> Part1.run() |> dbg()
end
test "part 2" do
assert @example_input |> Input.to_stream() |> Part2.run() === 45000
@input |> Input.to_stream() |> Part2.run() |> dbg()
end
end
ExUnit.configure(trace: true)
ExUnit.run()
```
See source 
