public void SubtractNegLeftPositiveRight()
 {
     Assert.AreEqual(-13, BitOp.Subtract(-5, 8));
 }
 public void SubtractPositiveLeftNegativeRight()
 {
     Assert.AreEqual(8, BitOp.Subtract(7, -1));
 }
 public void SubtractTwoPositives()
 {
     Assert.AreEqual(-9, BitOp.Subtract(2, 11));
 }