Submission #17059291

---

Source Code Expand

defmodule Main do
  def main do
    n = IO.read(:line) |> String.trim() |> String.to_integer()
    list = IO.read(:line) |> String.trim() |> String.split(" ") |> Enum.map(&String.to_integer/1)

    solve(n, list) |> IO.puts()
  end

  def solve(n, list) do
    0..(n - 1)
    |> Enum.reduce({Enum.sum(list), 0}, fn i, {sum, ans} ->
      sum = sum - Enum.at(list, i)
      ans = ans + sum * Enum.at(list, i)
      {sum, ans}
    end)
    |> elem(1)
    |> rem(1000000007)
  end
end

Submission Info

Judge Result