12 lines
417 B
Text
12 lines
417 B
Text
defmodule Queue do
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def new, do: {Queue, [], []}
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def push({Queue, input, output}, x), do: {Queue, [x|input], output}
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def pop({Queue, [], []}), do: (raise RuntimeError, message: "empty Queue")
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def pop({Queue, input, []}), do: pop({Queue, [], Enum.reverse(input)})
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def pop({Queue, input, [h|t]}), do: {h, {Queue, input, t}}
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def empty?({Queue, [], []}), do: true
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def empty?({Queue, _, _}), do: false
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end
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