private static void CheckStandardNotation(DD x, string expectedStr)
        {
            string xStr = x.ToStandardNotation();

            // System.Console.WriteLine("Standard Notation: " + xStr);
            Assert.AreEqual(expectedStr, xStr);
        }
	private static void CheckStandardNotation(DD x, String expectedStr) {
		String xStr = x.ToStandardNotation();
		Console.WriteLine("Standard Notation: " + xStr);
		Assert.AreEqual(expectedStr, xStr);
	}