Question 1

Run-time type information can be used to determine:

Accepted Answer

A)  A function's return type. 
B)  A function's argument type. 
C)  An object's type. 
D)  The number of arguments a function takes. 
A)  A function's return type. 
B)  A function's argument type. 
C)  An object's type. 
D)  The number of arguments a function takes. C

Question 2

Which of the following assignments would be a compilation error?

Accepted Answer

A)  Assigning the address of a base-class object to a base-class pointer. 
B)  Assigning the address of a base-class object to a derived-class pointer. 
C)  Assigning the address of a derived-class object to a base-class pointer. 
D)  Assigning the address of a derived-class object to a derived-class pointer. 
A)  Assigning the address of a base-class object to a base-class pointer. 
B)  Assigning the address of a base-class object to a derived-class pointer. 
C)  Assigning the address of a derived-class object to a base-class pointer. 
D)  Assigning the address of a derived-class object to a derived-class pointer. B

Question 3

The main difference between a pure virtual function and a virtual function is:

Accepted Answer

A)  The return type. 
B)  The member access specifier. 
C)  That a pure virtual function cannot have an implementation. 
D)  The location in the class. 
A)  The return type. 
B)  The member access specifier. 
C)  That a pure virtual function cannot have an implementation. 
D)  The location in the class. C

Question 4

Polymorphism is implemented via:

Accepted Answer

A)  Member functions. 
B)  virtual functions and dynamic binding. 
C)  inline functions. 
D)  Non-virtual functions. 
A)  Member functions. 
B)  virtual functions and dynamic binding. 
C)  inline functions. 
D)  Non-virtual functions.

Question 5

If objects of all the classes derived from the same base class all need to draw themselves, the draw) function would most likely be declared:

Accepted Answer

A)  private 
B)  virtual 
C)  protected 
D)  friend 
A)  private 
B)  virtual 
C)  protected 
D)  friend

Question 6

Abstract classes:

Accepted Answer

A)  Contain at most one pure virtual function. 
B)  Can have objects instantiated from them if the proper permissions are set. 
C)  Cannot have abstract derived classes. 
D)  Are defined, but the programmer never intends to instantiate any objects from them. 
A)  Contain at most one pure virtual function. 
B)  Can have objects instantiated from them if the proper permissions are set. 
C)  Cannot have abstract derived classes. 
D)  Are defined, but the programmer never intends to instantiate any objects from them.

Question 7

Problems using switch logic to deal with many objects of different types do not include:

Accepted Answer

A)  Forgetting to include an object in one of the cases. 
B)  Having to update the switch statement whenever a new type of object is added. 
C)  Having to track down every switch statement to do an update of object types. 
D)  Not being able to implement separate functions on different objects. 
A)  Forgetting to include an object in one of the cases. 
B)  Having to update the switch statement whenever a new type of object is added. 
C)  Having to track down every switch statement to do an update of object types. 
D)  Not being able to implement separate functions on different objects.

Question 8

The line:
Virtual double functionX) const = 0;
In a class definition indicates that the class is probably a:

Accepted Answer

A)  Base class. 
B)  Derived class. 
C)  Protected class. 
D)  Library class. 
A)  Base class. 
B)  Derived class. 
C)  Protected class. 
D)  Library class.

Question 9

The C++ compiler makes objects take up more space in memory if they:

Accepted Answer

A)  Are derived from base classes. 
B)  Have virtual functions. 
C)  Have only protected members. 
D)  Are referenced by pointers. 
A)  Are derived from base classes. 
B)  Have virtual functions. 
C)  Have only protected members. 
D)  Are referenced by pointers.

Question 10

Which of the following would not be a member function that derived classes Fish, Frog and Bird should inherit from base class Animal and then provide their own definitions for, so that the function call can be performed polymorphically?

Accepted Answer

A)  eat 
B)  sleep 
C)  move 
D)  flapWings 
A)  eat 
B)  sleep 
C)  move 
D)  flapWings

Question 11

Which of the following statements about virtual functions is false?

Accepted Answer

A)  They allow the program to select the correct implementation at execution time. 
B)  They can use either static or dynamic binding, depending on the handles on which the functions are called. 
C)  They do not remain virtual down the inheritance hierarchy. 
D)  They can be called using the dot operator. 
A)  They allow the program to select the correct implementation at execution time. 
B)  They can use either static or dynamic binding, depending on the handles on which the functions are called. 
C)  They do not remain virtual down the inheritance hierarchy. 
D)  They can be called using the dot operator.

Question 12

Virtual functions must:

Accepted Answer

A)  Be overridden in every derived class. 
B)  Be declared virtual in every derived class. 
C)  Be declared virtual in the base class. 
D)  Have the same implementation in every derived class. 
A)  Be overridden in every derived class. 
B)  Be declared virtual in every derived class. 
C)  Be declared virtual in the base class. 
D)  Have the same implementation in every derived class.

Question 13

Abstract classes do not necessarily have:

Accepted Answer

A)  A 0 pointer in their vtable. 
B)  A virtual function prototype with the notation = 0. 
C)  Zero instances of their class. 
D)  Zero references to their class. 
A)  A 0 pointer in their vtable. 
B)  A virtual function prototype with the notation = 0. 
C)  Zero instances of their class. 
D)  Zero references to their class.

Question 14

An abstract class will:

Accepted Answer

A)  Have all zeros in its vtable. 
B)  Have at least one 0 in its vtable. 
C)  Share a vtable with a derived class. 
D)  Have fewer 0's in its vtable than concrete classes have. 
A)  Have all zeros in its vtable. 
B)  Have at least one 0 in its vtable. 
C)  Share a vtable with a derived class. 
D)  Have fewer 0's in its vtable than concrete classes have.

Question 15

Employee is a base class and HourlyWorker is a derived class, with a redefined non-virtual print function. Given the following statements, will the output of the two print function calls be identical?
HourlyWorker h;
Employee *ePtr = &h;
EPtr->print);
EPtr->Employee::print);

Accepted Answer

A)  Yes. 
B)  Yes, if print is a static function. 
C)  No. 
D)  It would depend on the implementation of the print function. 
A)  Yes. 
B)  Yes, if print is a static function. 
C)  No. 
D)  It would depend on the implementation of the print function.

Question 16

Concrete classes that inherit virtual functions but do not override their implementations:

Accepted Answer

A)  Have vtables which are the same as those of their base classes. 
B)  Receive their own copies of the virtual functions. 
C)  Receive pointers to their base classes' virtual functions. 
D)  Receive pointers to pure virtual functions. 
A)  Have vtables which are the same as those of their base classes. 
B)  Receive their own copies of the virtual functions. 
C)  Receive pointers to their base classes' virtual functions. 
D)  Receive pointers to pure virtual functions.

Question 17

Virtual destructors must be used when:

Accepted Answer

A)  The constructor in the base class is virtual. 
B)  delete is used on a base-class pointer to a derived-class object. 
C)  delete is used on a derived-class object. 
D)  A constructor in either the base class or derived class is virtual. 
A)  The constructor in the base class is virtual. 
B)  delete is used on a base-class pointer to a derived-class object. 
C)  delete is used on a derived-class object. 
D)  A constructor in either the base class or derived class is virtual.

Question 18

The line:
Virtual double earnings) const = 0;
Appears in a class definition. You cannot deduce that:

Accepted Answer

A)  All classes that directly inherit from this class will override this method. 
B)  This class is an abstract class. 
C)  Any concrete class derived from this class will have an earnings function. 
D)  This class will probably be used as a base class for other classes. 
A)  All classes that directly inherit from this class will override this method. 
B)  This class is an abstract class. 
C)  Any concrete class derived from this class will have an earnings function. 
D)  This class will probably be used as a base class for other classes.

Question 19

The __________ operator returns a reference to a __________ object:

Accepted Answer

A)  typeid, type_info 
B)  typeinfo, type_id 
C)  typeid, data_type 
D)  typeinfo, type 
A)  typeid, type_info 
B)  typeinfo, type_id 
C)  typeid, data_type 
D)  typeinfo, type

Question 20

Which of the following is not allowed?

Accepted Answer

A)  Objects of abstract classes. 
B)  Multiple pure virtual functions in a single abstract class. 
C)  References to abstract classes. 
D)  Arrays of pointers to abstract classes. 
A)  Objects of abstract classes. 
B)  Multiple pure virtual functions in a single abstract class. 
C)  References to abstract classes. 
D)  Arrays of pointers to abstract classes.

Exam 13: Object-Oriented Programming: Polymorphism

Run-time type information can be used to determine:

Which of the following assignments would be a compilation error?

The main difference between a pure virtual function and a virtual function is:

Polymorphism is implemented via:

If objects of all the classes derived from the same base class all need to draw themselves, the draw) function would most likely be declared:

Abstract classes:

Problems using switch logic to deal with many objects of different types do not include:

The line: Virtual double functionX) const = 0; In a class definition indicates that the class is probably a:

The C++ compiler makes objects take up more space in memory if they:

Which of the following would not be a member function that derived classes Fish, Frog and Bird should inherit from base class Animal and then provide their own definitions for, so that the function call can be performed polymorphically?

Which of the following statements about virtual functions is false?

Virtual functions must:

Abstract classes do not necessarily have:

An abstract class will:

Employee is a base class and HourlyWorker is a derived class, with a redefined non-virtual print function. Given the following statements, will the output of the two print function calls be identical? HourlyWorker h; Employee *ePtr = &h; EPtr->print); EPtr->Employee::print);

Concrete classes that inherit virtual functions but do not override their implementations:

Virtual destructors must be used when:

The line: Virtual double earnings) const = 0; Appears in a class definition. You cannot deduce that:

The __________ operator returns a reference to a __________ object:

Which of the following is not allowed?

Introduction to Computers, the Internet and the World Wide Web

Introduction to C Programming

Control Statements, Part 1

Control Statements, Part 2

Functions and an Introduction to Recursion

Arrays and Vectors

Pointers and Pointer-Based Strings

Sequential-Access Files

Classes

Classes: a Deeper Look, Part 2

Operator Overloading; String and Array Objects

Object-Oriented Programming: Inheritance

Templates

Stream Inputoutput

Exception Handling

File Processing

Class String and String Stream Processing

Searching and Sorting

Data Structures

Standard Template Library Stl

Bits, Characters, C Strings and Structs

Boost Libraries, Technical Report 1 and C0x

Other Topics

ATM Case Study, Part 1: Object-Oriented Design With the Uml

ATM Case Study, Part 2: Implementing an Object-Oriented Design

Game Programming With Ogre

Filters

The operator returns a reference to a object: