Question 1

Inside a function definition for a member function of an object with data element x, which of the following is not equivalent to this->x:
A) *this.x
B) *this).x
C) x
D) * & *this) ) ).x

Accepted Answer

Option A is not equivalent as it uses dot notation to access the member variable x of the object using a pointer dereference operator. The correct syntax would be to use the arrow operator -> to access the member variable of the object pointed to by 'this', like this->x. Option B is also incorrect as it has an extra closing parenthesis. Option D is unnecessarily complex and convoluted. Option C is equivalent to this->x and is the best choice.

Question 2

If Americans are objects of the same class, which of the following attributes would most likely be represented by a static variable of that class?
A) Age.
B) The President.
C) Place of birth.
D) Favorite food.

Accepted Answer

The President is a static attribute because there is only one President at a time and it doesn't change with each individual American.

Question 3

When composition one object having another object as a member) is used:
A) The host object is constructed first and then the member objects are placed into it.
B) Member objects are constructed first, in the order they appear in the host constructor's initializer list.
C) Member objects are constructed first, in the order they are declared in the host's class.
D) Member objects are destructed last, in the order they are declared in the host's class.

Accepted Answer

C

Question 4

Static member functions:
A) Can use the this pointer.
B) Can access only other static member functions and static data members.
C) Cannot be called until an object of their class is instantiated.
D) Can be declared const as well.

Accepted Answer

The answer of Static member functions:
A) Can use the this...

Question 5

Which of the following are true about an abstract data type?
I. Captures a data representation.
II. Defines the operations that are allowed on its data.
III. Replaces structured programming.
A) I, II and III.
B) I and II.
C) I and III.
D) II and III.

Accepted Answer

An abstract data type captures a data representation (I) and defines the operations that are allowed on its data (II). It does not necessarily replace structured programming (III), so option C and D can be eliminated. Therefore, option B is the best choice.

Question 6

Which of the following is not true about friend functions and friend classes?
A) A class can either grant friendship to or take friendship from another class using the friend keyword.
B) A friend declaration can appear anywhere in a class definition.
C) A friend of a class can access all of its private data member and member functions.
D) The friendship relationship is neither symmetric nor transitive.

Accepted Answer

A class can grant friendship to another class using the friend keyword, but it cannot take friendship from another class.

Question 7

An error occurs if:
A) A non-reference, non-const, primitive data member is initialized in the member initialization list.
B) An object data member is not initialized in the member initialization list.
C) An object data member does not have a default constructor.
D) An object data member is not initialized in the member initialization list and does not have a default constructor.

Accepted Answer

In C++, object data members must be initialized either in the member initialization list or in the constructor body. If an object data member is not initialized in the member initialization list and does not have a default constructor, then an error will occur. The other options (A, B, and C) may be considered bad programming practices, but they will not cause an error.

Question 8

The numbers 3, 2, 5, 7 are enqueued in a queue in that order, then three numbers are dequeued, and finally 3, 7, 9, 4 are enqueued in that order. What is the first number in the queue the next number to be dequeued)?
A) 3
B) 7
C) 9
D) 4

Accepted Answer

The queue is initially: 3 -> 2 -> 5 -> 7
After dequeuing three numbers, the queue becomes: 7 -> null
Then, 3, 7, 9, 4 are enqueued in that order, making the queue: 7 -> 3 -> 7 -> 9 -> 4
The next number to be dequeued is the first number in the queue, which is 7.

Question 9

Assume that t is an object of class Test, which has member functions a), b), c) and d). If the functions a), b) and c) all return references to an object of class Test using the dereferenced this pointer) and function d) returns void, which of the following statements will not produce a syntax error:
A) t.a).b).d);
B) a).b).t;
C) t.d).c);
D) t.a).t.d);

Accepted Answer

CDA) This is a valid statement because a() returns a reference to a Test object, allowing b() to be called on the result, and then d() is called on the result of b(). Since d() returns void, no further method chaining is possible, but the statement is syntactically correct up to this point.B) This statement is incorrect because it attempts to call a() without an object, assuming a() is a non-static member function, and then tries to access t as if it were a member function of the result of b(), which is not syntactically valid.C) This statement will produce a syntax error because d() returns void, so attempting to call c() on the result of d() is not possible.D) This statement is incorrect because it attempts to call t as if it were a method of the object returned by a(), which is not syntactically valid.

Question 10

For a non-constant member function of class Test, the this pointer has type:
A) const Test *
B) Test * const
C) Test const *
D) const Test * const

Accepted Answer

The "this" pointer in a non-constant member function of a class is of type "Test * const". This means it is a constant pointer to a non-constant object of the class Test. It implies that while the pointer itself cannot be changed to point to a different object, the object it points to can be modified through this pointer.

Question 11

Which of the following statements will not produce a syntax error?
A) Defining a const member function that modifies a data member of the object.
B) Invoking a non-const member function on a const object.
C) Declaring an object to be const.
D) Declaring a constructor to be const.

Accepted Answer

Declaring an object to be const is valid syntax and does not produce a syntax error.

Question 12

Which of the following is not an abstract data type?
A) An int.
B) A user-defined class.
C) A for loop.
D) None of the above are abstract data types.

Accepted Answer

An int is a basic data type in many programming languages, while a user-defined class can be tailored to fit specific needs and is an example of an abstract data type. A for loop is a control statement used to iterate over a sequence of data and is not a data type at all. Therefore, the correct answer is C.

Question 13

Increment i )
{
Count = c;
}
Does not cause any compilation errors. This tells you that:
A) count must be a non-const variable.
B) count must be a const variable.
C) increment must be a non-const variable.
D) increment must be a const variable.

Accepted Answer

Since the function is setting the value of "count" equal to the value of "c", it is implicit that "count" is a non-const variable, otherwise the assignment would not be allowed. There is no mention of "increment" being a const or non-const variable in the given code, so any assumption about "increment" would be purely speculative.

Question 14

If the line:
Friend class A;
Appears in class B, and the line:
Friend class B;
Appears in class C, then:
A) Class A is a friend of class C.
B) Class A can access private variables of class B.
C) Class C can call class A's private member functions.
D) Class B can access class A's private variables.

Accepted Answer

Class A is a friend of class B, allowing it to access B's private variables.

Question 15

Static data members of a certain class:
A) Can be accessed only if an object of that class exists.
B) Cannot be changed, even by objects of the same that class.
C) Have class scope.
D) Can only be changed by static member functions.

Accepted Answer

Static data members have class scope, meaning they can be accessed without an object of the class and are shared by all objects of the class. They can be changed by static member functions, but not by regular member functions or objects of the class.

Quiz 10: Classes: a Deeper Look, Part 2

Inside a function definition for a member function of an object with data element x, which of the following is not equivalent to this->x:

If Americans are objects of the same class, which of the following attributes would most likely be represented by a static variable of that class?

When composition one object having another object as a member) is used:

Static member functions:

Which of the following are true about an abstract data type? I. Captures a data representation. II. Defines the operations that are allowed on its data. III. Replaces structured programming.

Which of the following is not true about friend functions and friend classes?

An error occurs if:

The numbers 3, 2, 5, 7 are enqueued in a queue in that order, then three numbers are dequeued, and finally 3, 7, 9, 4 are enqueued in that order. What is the first number in the queue the next number to be dequeued) ?

For a non-constant member function of class Test, the this pointer has type:

Which of the following statements will not produce a syntax error?

Which of the following is not an abstract data type?

Increment i ) { Count = c; } Does not cause any compilation errors. This tells you that:

If the line: Friend class A; Appears in class B, and the line: Friend class B; Appears in class C, then:

Static data members of a certain class: