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more tweaking

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This commit is contained in:
Adam Millerchip 2020-12-17 13:53:47 +09:00
parent 44092ab958
commit 07c5ebcb1e
1 changed files with 7 additions and 7 deletions
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14
day16/day16part2-simpler-transpose.exs
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@ -19,13 +19,13 @@ defmodule Day16Part2 do
end) end)
end end
def transpose_tickets(tickets) do def transpose_tickets(tickets), do: tickets |> Enum.zip() |> Enum.map(&Tuple.to_list/1)
tickets |> Enum.zip() |> Enum.map(&Tuple.to_list/1) |> Enum.with_index()
end
# Compare each column against the rules to determine the list of fields each column satisfies # Compare each column against the rules to determine the list of fields each column satisfies
def valid_fields_for_columns(transposed_tickets, rules) do def valid_fields_for_columns(transposed_tickets, rules) do
for {column, idx} <- transposed_tickets, do: {idx, valid_fields_for(column, rules)} for {column, idx} <- Enum.with_index(transposed_tickets) do
{valid_fields_for(column, rules), idx}
end
end end
# Reduce the list of valid fields by elimination. # Reduce the list of valid fields by elimination.
@ -35,10 +35,10 @@ defmodule Day16Part2 do
# Repeat for all columns. # Repeat for all columns.
def reduce_to_column_by_field_name(valid_fields_by_column) do def reduce_to_column_by_field_name(valid_fields_by_column) do
valid_fields_by_column valid_fields_by_column
|> Enum.sort_by(fn {_k, v} -> length(v) end) |> Enum.sort_by(fn {fields, _idx} -> length(fields) end)
|> Enum.map_reduce([], fn {col, fields}, seen -> |> Enum.map_reduce([], fn {fields, idx}, seen ->
[field] = fields -- seen [field] = fields -- seen
{{field, col}, [field | seen]} {{field, idx}, [field | seen]}
end) end)
|> elem(0) |> elem(0)
end end