62 lines
1.3 KiB
Elixir
62 lines
1.3 KiB
Elixir
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defmodule AOC.Day7 do
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def parse_input(lines), do: parse_input(lines, %{})
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def parse_input([], acc), do: acc
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def parse_input([str | tl], acc) do
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[container, str] = String.split(str, " bags contain ")
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inner =
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str
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|> String.split(", ")
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|> Enum.map(fn
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"no other bags." ->
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[]
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bags ->
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[num, adj1, adj2, _] = String.split(bags)
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{String.to_integer(num), "#{adj1} #{adj2}"}
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end)
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|> List.flatten()
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parse_input(tl, Map.put(acc, container, inner))
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end
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def find_golden_containers(map) do
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map
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|> Map.keys()
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|> Enum.filter(fn
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"shiny gold" -> false
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bag -> find_golden_containers(map, bag)
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end)
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end
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def find_golden_containers(_, "shiny gold"), do: true
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def find_golden_containers(map, bag) do
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map[bag]
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|> Enum.map(fn {_, x} -> find_golden_containers(map, x) end)
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|> Enum.any?()
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end
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def part1 do
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AOC.Util.input_lines(7, 1)
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|> parse_input()
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|> find_golden_containers()
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|> Enum.count()
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end
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def count_bags(map), do: count_bags(map, "shiny gold")
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def count_bags(map, bag) do
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map[bag]
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|> Enum.map(fn {n, x} -> n * (count_bags(map, x) + 1) end)
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|> Enum.sum()
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end
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def part2 do
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AOC.Util.input_lines(7, 1)
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|> parse_input()
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|> count_bags()
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end
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end
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