78 lines
1.3 KiB
Markdown
78 lines
1.3 KiB
Markdown
# Day02
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```elixir
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Mix.install([
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{:kino, "~> 0.14.2"},
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])
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```
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## Run Me
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[](https://livebook.dev/run?url=https%3A%2F%2Fgit.kev.pub%2Fkev%2Faoc2024%2Fraw%2Fbranch%2Fmain%2Fday01.livemd)
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## Input
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```elixir
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input = Kino.Input.textarea("Input")
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```
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## Part One
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```elixir
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defmodule PartOne do
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def differences([_]), do: []
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def differences([a, b|t]), do: [a - b| differences([b|t])]
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def parse(input) do
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input
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|> Kino.Input.read
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|> String.split("\n")
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|> Enum.map(fn l -> l |> String.split(" ")|> Enum.map(&String.to_integer/1) end)
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end
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def pass_diffs(l) do
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fail = l
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|> PartOne.differences
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|> Enum.any?(fn y -> (abs(y) > 3 || y == 0) end)
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!fail
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end
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def pass_direction(l) do
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l =
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l
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|> PartOne.differences
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|> Enum.map(fn x -> x > 0 end)
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|> Enum.dedup
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|> length
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l == 1
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end
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def passes(x), do: pass_diffs(x) && pass_direction(x)
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end
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input
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|> PartOne.parse
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|> Enum.count(&PartOne.passes/1)
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```
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## Part Two
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```elixir
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%{false: fails, true: passes} =
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input
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|> PartOne.parse
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|> Enum.group_by(&PartOne.passes/1)
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fail_count = Enum.map(fails, fn l ->
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0..length(l)
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|> Enum.map(fn x -> List.delete_at(l,x) end)
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|> Enum.any?(&PartOne.passes/1)
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end)
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|> Enum.count(fn x -> x end)
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length(passes) + fail_count
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```
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