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<!-- livebook:{"file_entries":[{"name":"day2.txt","type":"attachment"}]} -->
# Day 2
```elixir
Mix.install([
{:kino, "~> 0.13.0"}
])
```
## Part 1
```elixir
content =
Kino.FS.file_path("day2.txt")
|> File.read!()
|> String.trim()
```
```elixir
defmodule SeqTest do
def increasing?(list) do
list
|> Enum.chunk_every(2, 1, :discard)
|> Enum.reduce(true, fn [a, b], acc ->
acc and (b - a <= 3 and b - a > 0)
end)
end
def decreasing?(list) do
list
|> Enum.chunk_every(2, 1, :discard)
|> Enum.reduce(true, fn [a, b], acc ->
acc and (a - b <= 3 and a - b > 0)
end)
end
end
safe_reports =
content
|> String.split("\n")
|> Enum.map(fn line ->
String.split(line)
|> Enum.map(fn num -> String.to_integer(num) end)
end)
|> Enum.count(fn line ->
SeqTest.increasing?(line) or SeqTest.decreasing?(line)
end)
```
## Part 2
```elixir
defmodule Dampener do
def dampened_lists(report) do
for i <- 0..(length(report) - 1) do
List.delete_at(report, i)
end
end
end
safe_problem_dampener =
content
|> String.split("\n")
|> Enum.map(fn line ->
String.split(line)
|> Enum.map(fn num -> String.to_integer(num) end)
end)
|> Enum.count(fn line ->
line
|> Dampener.dampened_lists()
|> Enum.any?(fn single -> SeqTest.increasing?(single) or SeqTest.decreasing?(single) end)
end)
```
See source 
