Problem
Write a program to handle the flow of widgets into and out of a warehouse. The warehouse will have numerous deliveries of new widgets and orders for widgets. The widgets in a filled order are billed at a profit of 50 percent over their cost. Each delivery of new widgets may have a different cost associated with it. The accountants for the firm have instituted a last-in, first-out system for filling orders. This means that the newest widgets are the first ones sent out to fill an order. Also, the most recent orders are filled first. This function of inventory can be represented using two stacks: orders-to-be-filled and widgets-on-hand. When a delivery of new widgets is received, any unfilled orders (on the orders-to-be-filled stack) are processed and filled. After all orders are filled, if there are widgets remaining in the new delivery, a new element is pushed onto the widgets-onhand stack. When an order for new widgets is received, one or more objects are popped from the widgets-on-hand stack until the order has been filled. If the order is completely filled and there are widgets left over in the last object popped, a modified object with the quantity updated is pushed onto the widgets-on-hand stack. If the order is not completely filled, the order is pushed onto the orders-to-be-filled stack with an updated quantity of widgets to be sent out later. If an order is completely filled, it is not pushed onto the stack. Write a class with functions to process the shipments received and to process orders. After an order is filled, display the quantity sent out and the total cost for all widgets in the order. Also indicate whether there are any widgets remaining to be sent out at a later time. After a delivery is processed, display information about each order that was filled with this delivery and indicate how many widgets, if any, were stored in the object pushed onto the widgets-on-hand stack.