defmodule Main do
  def main do
    IO.read(:line)
    |> String.split()
    |> Enum.map(&String.to_integer/1)
    |> solve
    |> IO.puts()
  end

  defp solve([a, b]) do
    yes_or_no =
      cond do
        a >= b -> "NO"
        true -> "YES"
      end

    """
    #{yes_or_no}
    #{(a - b + 1) |> abs}
    """
    |> String.trim
  end
end