Write an application that calculates the total cost of new carpet for a rectangular room. The application should first ask the user for the current cost of the carpet per square foot. It then asks for both the length and width of the room and displays the total cost. It will continue until the user enters 0 for either the length or width. The application should also trap for any negative lengths or widths and allow the user to re-enter them until they give a non-negative value.