24 lines
635 B
Elixir
24 lines
635 B
Elixir
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defmodule Solution do
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@spec two_sum(nums :: [integer], target :: integer) :: [integer]
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def two_sum(nums, target) do
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process_num(nums, target)
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end
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@spec process_num(
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nums :: [integer],
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target :: integer,
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head_idx :: integer,
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indexes :: %{integer => integer}
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) :: [integer]
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defp process_num([head | tail], target, head_idx \\ 0, indexes \\ %{}) do
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first_idx = indexes[target - head]
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if first_idx != nil do
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[first_idx, head_idx]
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else
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indexes = Map.put(indexes, head, head_idx)
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process_num(tail, target, head_idx + 1, indexes)
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end
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end
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end
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