Increment and Decrement
	• Two other operators that are useful are the increment and decrement operators (++ and --). • Remember these operators can be used in both the prefix and postfix form, and have very different meanings. • In the prefix form, the residual value is the post incremented or post decremented value. • In the postfix form, the residual value is the pre incremented or pre decremented value. • These are unary operators, so they should be overloaded as members.