28 lines
756 B
Elixir
28 lines
756 B
Elixir
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defmodule Solution do
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@spec max_area(height :: [integer]) :: integer
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def max_area(height) do
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iter(0, height, 0, 0)
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end
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defp iter(prev, [head | tail], head_idx, max_vol) do
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if prev >= head do
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iter(prev, tail, head_idx + 1, max_vol)
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else
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max_vol = iter_inner(head, head_idx, tail, head_idx + 1, max_vol)
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iter(head, tail, head_idx + 1, max_vol)
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end
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end
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defp iter(_, [], _, max_vol), do: max_vol
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defp iter_inner(a, a_idx, [head | tail], head_idx, max_vol) do
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distance = head_idx - a_idx
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min_height = min(a, head)
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volume = min_height * distance
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max_vol = max(max_vol, volume)
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iter_inner(a, a_idx, tail, head_idx + 1, max_vol)
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end
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defp iter_inner(_, _, [], _, max_vol), do: max_vol
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end
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