24 lines
547 B
Elixir
24 lines
547 B
Elixir
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defmodule Leetcode do
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@doc """
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LeetCode #1: two_sum
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TODO: store a map of complements (differences) as iterating for O(n)
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"""
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@spec two_sum(list, int, int) :: any
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def two_sum(_, _, i \\ 0)
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def two_sum(nums, target, current_index \\ 0)
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def two_sum([], _target, _i), do: nil
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def two_sum([cur | rest], target, current_index) do
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case Enum.find_index(rest, fn x -> cur + x == target end) do
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nil -> two_sum(rest, target, current_index + 1)
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i -> [current_index, 1 + current_index + i]
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end
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end
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# ...
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end
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