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# Day 6

## Section

```elixir
initial = for i <- 0..8, into: %{}, do: {i, 0}

counts =
  File.read!("day6.txt")
  |> String.trim()
  |> String.split(",")
  |> Enum.map(&String.to_integer/1)
  |> Enum.frequencies()
  |> Map.merge(initial, fn _, a, _ -> a end)

defmodule Day6 do
  def next(%{0 => next} = population) do
    1..8
    |> Map.new(&{&1 - 1, population[&1]})
    |> Map.merge(%{6 => next, 8 => next}, fn _, v1, v2 -> v1 + v2 end)
  end
end
```

```output
{:module, Day6, <<70, 79, 82, 49, 0, 0, 7, ...>>, {:next, 1}}
```

## Task 1

```elixir
1..80
|> Enum.reduce(counts, fn _, acc -> Day6.next(acc) end)
|> Map.values()
|> Enum.sum()
```

```output
343441
```

## Task 2

```elixir
1..256
|> Enum.reduce(counts, fn _, acc -> Day6.next(acc) end)
|> Map.values()
|> Enum.sum()
```

```output
1569108373832
```