defmodule Main do
  def input, do: IO.read(:line) |> String.trim
  def ii, do: input() |> String.to_integer
  def li, do: input() |> String.split |> Enum.map(&String.to_integer/1)
  def yn(b), do: IO.puts (if b, do: "Yes", else: "No")

  def main do
    _n = ii()
    a = li() |> Enum.sort |> Enum.uniq

    if length(a) == 1 do
      IO.puts 0
      System.halt(0)
    end

    for [a, b] <- Enum.chunk_every(a, 2, 1) do
      abs(a - b)
    end
    |> Enum.min
    |> IO.puts
  end
end