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# Advent 2024 - Day 2
```elixir
Mix.install([
{:kino, "~> 0.14.2"}
])
```
## Setup
```elixir
input = Kino.Input.textarea("Please paste your input file")
```
```elixir
reports =
input
|> Kino.Input.read()
|> String.split("\n")
|> Enum.map(fn line ->
line
|> String.split(" ")
|> Enum.map(&String.to_integer(&1))
end)
```
## Part 1
```elixir
defmodule RedNoseReports do
def process([a | [b | t]]) do
if a - b > 0 do
process([a | [b | t]], :up)
else
process([a | [b | t]], :down)
end
end
def process([a | [b | t]], direction) do
correct_direction = case direction do
:up -> a - b > 0
:down -> a - b < 0
end
diff = abs(b - a)
if (diff > 3 or diff == 0) or not correct_direction do
false
else
process([b | t], direction)
end
end
def process(report, _direction) when is_list(report) and length(report) == 1 do
true
end
end
for report <- reports do
RedNoseReports.process(report)
end
|> Enum.count(&(&1))
```
## Part 2
```elixir
for report <- reports do
if RedNoseReports.process(report) do
true
else
for index_to_remove <- 0..length(reports) do
modified_report =
report
|> Enum.with_index()
|> Enum.reject(fn {_value, index} -> index == index_to_remove end)
|> Enum.map(fn {value, _index} -> value end)
RedNoseReports.process(modified_report)
end
|> Enum.any?
end
end
|> Enum.count(&(&1))
```
See source 
