Question 1

A Member function that allows the user of the class to see the value in a data member is known as
A) a mutator function
B) a mutation
C) a manipulator function
D) an accessor function

Accepted Answer

An accessor function is a member function that allows the user of the class to access or return the value in a data member without modifying it. It is also known as a getter function. The other choices - a mutator function (A) is used to modify the value of a data member, a mutation (B) is a process of changing the genetic structure of an organism, and a manipulator function (C) is used to manipulate the input/output streams in C++.

Question 2

Data members or member functions of a class that are declared to be private may
A) only be accessed by the main program
B) only be accessed by members of the class
C) not be accessed by the class
D) are considered to be global variables

Accepted Answer

Private data members and member functions can only be accessed by members of the class in which they are declared. This is a fundamental aspect of encapsulation, which allows classes to manage their own data and behavior, while hiding implementation details from outside code. Access to private members by the main program or other classes is restricted to prevent unintended changes or misuse of the class. Hence, the correct answer is B.

Question 3

Member functions of a class
A) may not be in the private section
B) must be in the private section
C) may be in either section
D) can not be called in the main program

Accepted Answer

Member functions can be in either the public, private, or protected sections of a class. There are no restrictions on where they can be placed. However, their accessibility from outside the class depends on where they are placed. If a member function is in the private section, only other member functions can access it. If it is in the public section, it can be accessed by both member functions and non-member functions.

Question 4

In a class, all members are ____________ by default
A) public
B) private
C) global
D) all of the above

Accepted Answer

In a class, all members are private by default, which means they can only be accessed within the class. If we want to make certain members accessible outside the class, we can declare them public. Global is not a valid access specifier for class members.

Question 5

In a struct, all members are ____________ by default
A) public
B) private
C) global
D) all of the above

Accepted Answer

In C++ and C#, the members of a struct are public by default.

Question 6

Which part of the ADT tells the programmer using it how to use it?
A) the implementation
B) the interface
C) the abstractness
D) the scope resolution

Accepted Answer

The interface of an ADT defines the methods available to the programmer and how to use them. The implementation is the actual code that makes the ADT work, and the abstractness and scope resolution are not directly related to the use of the ADT by the programmer.

Question 7

Given the following class definition, what is missing?
Class ItemClass
{
Public:
ItemClassint newSize, float newCost);
Int getSize);
Float getCost);
Void setSizeint newSize);
Void setCostfloat newCost);
Private:
Int size;
Float cost;
};
A) nothing
B) a default constructor
C) accessor functions
D) mutator functions

Accepted Answer

The class definition only includes a constructor that takes two arguments. It does not include a default constructor (one with no arguments), so it is missing.

Question 8

Given the following class, what would be the best declaration for a constructor that would allow the user to initialize the object with an initial age and cost?
Class Wine
{
Public:
Wine);
Int getAge);
Float getCost);
Private:
Int age;
Float cost;
}
A) int getAgeint newAge);
B) Wine);
C) Wineint age);
D) Wineint newAge, float newCost);

Accepted Answer

The constructor should have the same name as the class and should be declared with the parameters that the user should pass when creating an object of the class. In this case, the constructor should take in an integer for the age and a float for the cost. Therefore, option D is the best choice as it allows the user to initialize both age and cost.

Question 9

Given the following class and object declaration, how would you print out the age and cost of a bottle of wine?
Class Wine
{
Public:
Wine);
Int getAge);
Float getCost);
Private:
Int age;
Float cost;
}
Wine bottle;
A) cout << bottle;
B) cout << Wine.age, Wine.cost;
C) cout << bottle.getAge) << bottle.getCost);
D) cout << bottle.getAge << bottle.getCost;
E) cout << bottle.age << bottle.cost;

Accepted Answer

To print out the age and cost of a bottle of wine, we need to call the public member functions getAge() and getCost() on the object bottle. Option C combines the output of both these functions with the insertion operator << to print the values. Options A, B, D and E are incorrect because they either try to print the object directly, access the private members directly, or miss the parentheses after the member function names.

Question 10

A derived class has access to
A) the private functions and variables of its ancestor classes
B) the public functions and variables of its ancestor classes
C) only the functions and variables defined it its class
D) none of the above

Accepted Answer

A derived class has access to the public functions and variables of its ancestor/base classes, but not their private functions and variables. It can also add its own functions and variables.

Question 11

If you design a class with private data members, and do not provide mutators and accessors, then
A) The private data members can still be accessed from outside the class by using the & operator
B) The data can not be changed or viewed by anyone.
C) None of the above
D) A and B

Accepted Answer

Without mutators (setters) and accessors (getters), private data members in a class cannot be directly accessed or modified from outside the class. This encapsulation principle is fundamental in object-oriented programming to protect the integrity of the data.

Question 12

If you are designing a class for an ADT, you can tell if the class is an ADT if
A) when you change the implementation of the class, none of the rest of the program needs to change.
B) when you change the interface of the class, nothing else needs to change.
C) you change the privte part and the rest of the program using the ADT does not compile.
D) everything must be changed.

Accepted Answer

An Abstract Data Type (ADT) is defined by its behavior from the point of view of a user, in terms of possible values, possible operations on data of this type, and the behavior of these operations. This means that the implementation of the class can change (e.g., how the data is stored and manipulated internally), but as long as the interface (the way the class is used by the rest of the program) remains the same, none of the rest of the program needs to change. This encapsulation and separation of interface from implementation is a core concept in software engineering, allowing for flexibility and changes in implementation without affecting the overall system.

Question 13

A class member function that automatically initializes the data members of a class is called
A) the init function
B) an operator
C) a constructor
D) a cast

Accepted Answer

A constructor is a member function that is automatically called when an object of a class is created. It is used to initialize the data members of the class to specific values. Therefore, the correct choice is C. The other options, such as the init function, operator, and cast, do not have the same functionality as a constructor.

Question 14

Given the following class, what would be the best declaration for a mutator function that allows the user of the class to change the age?
Class Wine
{
Public:
Wine);
Int getAge);
Float getCost);
Private:
Int age;
Float cost;
}
A) int getAgeint newAge);
B) Wine);
C) void setAge);
D) void setAgeint newAge);

Accepted Answer

The best declaration for a mutator function to allow the user to change the age would be a void function with the name setAge and a single integer parameter newAge. This would allow the user to easily set the age of the Wine object to a new value. Option A is a getter function, not a mutator function. Option B is not a valid function declaration. Option C is a good name for a mutator function, but it needs a parameter to actually change the age value.

Question 15

If you have a class named myPersonClass, which of the following correctly declare a constructor in the class definition?
A) myPersonClass::myPersonClass);
B) myPersonClass);
C) init);
D) cast);

Accepted Answer

Option B correctly declares a constructor in the class definition. The syntax for declaring a constructor is the same as the class name followed by parenthesis. Options A, C, and D are not valid syntax for declaring a constructor.

Question 16

Given the following class definition, how would you declare an object of the class, so that the object automatically called the default constructor?
Class ItemClass
{
Public:
ItemClass);
ItemClassint newSize, float newCost);
Int getSize);
Float getCost);
Void setSizeint newSize);
Void setCostfloat newCost);
Private:
Int size;
Float cost;
};
A) ItemClass) myItem;
B) ItemClass myItem1, 0.0);
C) ItemClass myItem;
D) ItemClass myItem);
E) You can not do this

Accepted Answer

The default constructor is automatically called when an object is declared without any parameters, as in option C. The other options either provide arguments for the constructor or have incorrect syntax.

Question 17

A data type consisting of data members and operations on those members which can be used by a programmer without knowing the implementation details of the data type is called
A) an abstract definition type
B) an available data type
C) an abstract data type
D) a primitive data type

Accepted Answer

An abstract data type (ADT) is a data type in which only the behavior is defined and not the implementation. The data members and operations are abstracted from the user, providing a means of encapsulation and modularity in programming. ADTs can be seen as black boxes where the user only needs to know what the data type does, not how it does it.

Question 18

given the following class definition, how could you use the constructor to assign values to an object of this class?
Class CDAccount
{
Public:
CDAccount);
CDAccountfloat interest, float newBalance);
Float getBalance);
Float getRate);
Void setRatefloat interest);
Void setBalancefloat newBalance);
Private:
Float balance, rate;
};
And the following object declaration
CDAccount myAccount;
A) myAccount = CDAccountfloat myRate, float myBalance);
B) myAccount = CDAccount {myRate, myBalance};
C) myAccount = CDAccount[myRate, myBalance];
D) myAccount = CDAccountmyRate, myBalance);

Accepted Answer

The answer of given the following class definition, how could...

Question 19

Developing an ADT means that the user of your class does not have to know the details about how the class is implemented. This is known as
A) interface
B) implementation
C) testing and debugging
D) information hiding

Accepted Answer

Developing an ADT involves information hiding, which means that the implementation details are not exposed to the user. The user only interacts with the interface provided by the class, without knowing how it actually works. This improves encapsulation and promotes modular design.

Question 20

A member function that allow the user of the class to change the value in a data member is known as
A) a mutator function
B) a mutation
C) a manipulator function
D) an accessor function

Accepted Answer

A member function that allows the user to change a data member is known as a mutator function. This function typically begins with the prefix "set" followed by the name of the data member being modified. Mutator functions are also called "setters" because they set the value of a data member.

Quiz 10: Defining Classes

A Member function that allows the user of the class to see the value in a data member is known as

Data members or member functions of a class that are declared to be private may

Member functions of a class

In a class, all members are ____________ by default

In a struct, all members are ____________ by default

Which part of the ADT tells the programmer using it how to use it?

Given the following class definition, what is missing? Class ItemClass { Public: ItemClassint newSize, float newCost) ; Int getSize) ; Float getCost) ; Void setSizeint newSize) ; Void setCostfloat newCost) ; Private: Int size; Float cost; };

Given the following class, what would be the best declaration for a constructor that would allow the user to initialize the object with an initial age and cost? Class Wine { Public: Wine) ; Int getAge) ; Float getCost) ; Private: Int age; Float cost; }

Given the following class and object declaration, how would you print out the age and cost of a bottle of wine? Class Wine { Public: Wine) ; Int getAge) ; Float getCost) ; Private: Int age; Float cost; } Wine bottle;

A derived class has access to

If you design a class with private data members, and do not provide mutators and accessors, then

If you are designing a class for an ADT, you can tell if the class is an ADT if

A class member function that automatically initializes the data members of a class is called

Given the following class, what would be the best declaration for a mutator function that allows the user of the class to change the age? Class Wine { Public: Wine) ; Int getAge) ; Float getCost) ; Private: Int age; Float cost; }

If you have a class named myPersonClass, which of the following correctly declare a constructor in the class definition?

A data type consisting of data members and operations on those members which can be used by a programmer without knowing the implementation details of the data type is called

Developing an ADT means that the user of your class does not have to know the details about how the class is implemented. This is known as

A member function that allow the user of the class to change the value in a data member is known as