CMPS 200 Final, Fall 2005

Faculty of Arts & Sciences Department of Computer Science CMPS 200—Introduction to Computer Programming Fall 2005–2006 Tuesday, January 24, 2006 Final Exam Version 1 Name: Student Id: Signature: Section: Lect I 10–11 Lect II 1–2 Answers to Part I Question A B C D E 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. Grades Part I 50 Correct Incorrect Blank Part II 60 1.1 8 1.2 6 1.3 6 1.4 23 1.5 7 2 10 Total 110 Final Exam (2006-01-24) Initials: CMPS 200 10 of 19 Part II Answer the following questions in the space provided. Problem 1 The agencies funding the XYZ Theater Company have asked it to better keep track of the money it collects from tickets sales and maintain reduced prices for children and students thereby encouraging them to go to plays. As a friend of the theater, you volunteered to assist the Theater Company in completing the ticket sales application. The theater company has already designed the following classes: � Customer is an abstract class that defines the general properties of theater customers. This class is specialized by classes that define the properties of specific categories of customers. For example, the class CustomerChild specializes the Customer class to define the properties of child customers of the theater. � The class TheaterShow represents a theater show and defines, among others, methods for accounting and seat allocation. � The class TheaterDriver is a driver class that tests the functionality of the various other classes. Complete the implementation of the classes below. Final Exam (2006-01-24) Initials: CMPS 200 11 of 19 1. Implement the abstract class Customer. The class defines the instance variable receipt (int) that is initially set to -1 in the constructor. The class defines the abstract method getDiscount() which takes no parameters and returns a float. It also defines the setter method acceptReceipt() which sets the value of the instance variable receipt; it takes an int parameter and does not return a value. (8 points = 1 +1+ 2 + 2 + 2) // Class header .......................................................................................................................................................................... // Variable & Constant declarations .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Constructor .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Methods .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 12 of 19 2. Implement the CustomerChild class which specializes the class Customer. The class’s constructor initializes the receipt instance variable to –1. It also implements the method getDiscount() to always return the value 0.25. (6 points = 1+1+2+2) // Class header .......................................................................................................................................................................... // Variable & Constant declarations .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Constructor .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Methods .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 13 of 19 3. Implement the CustomerAdult class which specializes the class Customer. The class’s constructor initializes the receipt instance variable to –1. It also implements the method getDiscount() to always return the value 1.0. (6 points = 1+1+2+2) // Class header .......................................................................................................................................................................... // Variable & constant declarations .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Constructor .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Methods .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 14 of 19 4. Implement the TheaterShow class. The class defines two instance variables: count (int) to keep track of the number of seats occupied in a particular show; seats (array of Customer) to store the attendees of a show. The class defines a constant TICKET_PRICE to be 10,000; this value may be discounted depending on the customer’s age. The class also defines the following methods: � The constructor takes an int parameter, the number of seats in the theater. It validates this number and uses it to initialize a new Theatre Show object. An invalid parameter defaults to 100. � The private issueReceipt method returns 101 plus the number of currently allocated seats when there are available seats. It returns –1 otherwise. � The addCustomer method takes a Customer object as a parameter and does not return a value. It issues a receipt and, if successful, hands over the receipt to the customer (i.e., the customer accepts the receipt), and assigns the next available seat to the customer. This last action updates the count of allocated seats. Upon failure, the method should issue the error message: “Sorry, the theater is already full!”. � The showIncome method computes the Company’s income from a show and returns it as a float. � The toString method returns a string describing the number of seats sold in a show along with the show’s income. (23 points = 1+1+4 +3+7+5+2) // Class header .......................................................................................................................................................................... // Variable & constant declarations .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Constructor .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 15 of 19 // Method issueReceipt .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Method addCustomer .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 16 of 19 // Method showIncome .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... // Method toString .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 17 of 19 5. Implement the driver class TheaterDriver. This class’s main method instantiates a TheaterShow object, 2 CustomerChild objects, 3 CustomerStudent objects, and 4 CustomerAdult objects. It then adds all these Customer objects to the show object and issues a report on the show’s income. (7 points) .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... .......................................................................................................................................................................... Final Exam (2006-01-24) Initials: CMPS 200 18 of 19 Problem 2 An array of integers that represents a list of integers may contain repeated values. By contrast, an array of integers that represents a set does not contain any repetitions. (10 points) Implement the computeSetSize static method which accepts an int array as a parameter. This array is full and sorted in ascending order, but may contain repeated values. The method returns the size of the array’s corresponding set as an int value. The table below gives several examples: Array Return Value