quiz 3

Question 1

In a structure definition, the identifiers declared in the braces are called

Answer 1

member names

Question 2

You specify an individual member of a struct by using

Answer 2

The dot operator

Question 3

To assign values to a structure variable, you use the

Answer 3

assignment operator

Question 4

What is wrong with the following structure definition?
struct MyStruct
{
int size;
float weight;
}

Answer 4

missing semicolon

Question 5

Given the following strucure definitions, what is the correct way to print the person’s birth year?
struct DateType
{
int day;
int month;
int year;
};

struct PersonType
{
int age;
float weight;
DateType birthday;
};

PersonType person;

Answer 5

cout &laquo_space;person.birthday.year;

Question 6

Given the following strucure definition, what is the correct way to initialize a variable called today?
struct DateType
{
int day;
int month;
int year;
};

Answer 6

DateType today = {1,1,2000};

Question 7

When defining a class, the class should be composed of the kind of values a variable of the class can contain, and

Answer 7

member functions for that class

Question 8

Which of the following is the correct function definition header for the getAge function which is a member of the Person class?

Answer 8

int Person::getAge()

Question 9

Given the following class definition and the following member function header, which is the correct way to output the private data?
class Person
{
public:
void outputPerson(ostream& out);
private:
int age;
float weight;
int id;
};

void Person::outputPerson(ostream& out)
{
//what goes here?
}

Answer 9

out &laquo_space;age &laquo_space;weight &laquo_space;id;

Question 10

Why do you want to usually make data members private in a class?

Answer 10

ensure data integrity
provide data abstraction.
provide information hiding.

Question 11

A member function of a class should be made private

Answer 11

if it will only be used by other members of the class

Question 12

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

Answer 12

a mutator function

Question 13

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

Answer 13

an accessor function

Question 14

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

Answer 14

The data can not be changed or viewed by anyone.

Question 15

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

Answer 15

a constructor

Question 16

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

Answer 16

myPersonClass();

Question 17

given the following class definition, how could you use the constructor to assign values to an object of this class?

class CDAccount
{
public:
CDAccount();
CDAccount(float interest, float newBalance);
float getBalance();
float getRate();
void setRate(float interest);
void setBalance(float newBalance);
private:
float balance, rate;
};

and the following object declaration
CDAccount myAccount;

Answer 17

myAccount = CDAccount(myRate, myBalance);

Question 18

Given the following class definition, what is missing?
class ItemClass
{
public:
ItemClass(int newSize, float newCost);
int getSize();
float getCost();
void setSize(int newSize);
void setCost(float newCost);
private:
int size;
float cost;
};

Answer 18

a default constructor

Question 19

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();
ItemClass(int newSize, float newCost);
int getSize();
float getCost();
void setSize(int newSize);
void setCost(float newCost);
private:
int size;
float cost;
};

Answer 19

ItemClass myItem;

Question 20

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

Answer 20

an abstract data type