Exam 1

Question 1

True or False

A struct data type can include variables.

Answer 1

True

Question 2

True or False

A struct data type include functions.

Answer 2

True

Question 3

Variables declared in a struct data type are called

Answer 3

Data Fields / Data Members

Question 4

Functions declared in a struct data type are called

Answer 4

Member Functions

Question 5

True or False

A function prototype require names of parameter variables

Answer 5

False

Question 6

Why don’t function prototypes require names of parameter variables?

Answer 6

Variable names are not required in the function prototype. The compiler will ignore them. This also means that the variable names used in the function prototype do not need to match those used in the actual function itself.

Question 7

When you define a new data type, Role or Employee, in our projects, in a separate header file, what preprocessing directives need to be added?

Answer 7

endif

#ifndef EMPLOYEE_H
#define EMPLOYEE_H

Question 8

Explain the reason why you include preprocessing directives

Answer 8

endif specifies the end of a conditional directive

This prevent from the multiple inclusion of same header file multiple time.

The #ifndef , if not defined, directive checks if the identifier has not been defined, or if its definition has been removed with #undef, the condition is true (nonzero). Otherwise, the condition is false (0).

The #define creates a macro, which is the association of an identifier or parameterized identifier with a token string. After the macro is defined, the compiler can substitute the token string for each occurrence of the identifier in the source file.

Question 9

When a singly linked list is used to store a collection of data items, each data item is stored in a _________, which includes an additional variable whose data type is a _______________.

Answer 9

Node , Node pointer

Question 10

If you keep a variable that points to ________ , you can visit each data item in a single linked list.

Answer 10

Head

Question 11

The arrow operator (->) is used when _______________

Answer 11

The arrow operator is used with a pointer to an object.

To access members of a structure through a pointer

a->b is the same notation as (*a).b

. Takes precedence so you have to () to do *a first.
-> is short hand

Question 12

In a singly linked list, the pointer in the last node in the list typically points to ________

Answer 12

NULL

Question 13

If you have a node pointer named head, which is pointing to a valide node, how do you access the member variable in the node named item?

A. head.item
B. *head.item
C. (*head).item
D. head->item
E. All of the above
F. A or B
G. C or D

Answer 13

G. C or D

(*head).item

head->item

Question 14

Given the following declarations, how would you know if head is pointing to an empty list?

struct Node
{
    int number;
    Node* next;
};

Node* head;
// some other code here

A. if(head->next == NULL)
B. if(head == null)
C. if(head == NULL)
D. if(head->next==null);
E. A and D
F. B and C

Answer 14

C. if(head == NULL)

Question 15

The actual value of NULL is

A. -1
B. 0
C. 99999
D. -99

Answer 15

B. 0

Question 16

When do you use typedef? Write a code of an example

Answer 16

Define an alias of existing data type

typedef Employee EMP;

Question 17

Which of the following loops correctly uses inter in order to move through the nodes of the linked list?

Node *iter;

A. while(iter != NULL)
iter++;
B. while(iter != NULL)
iter = iter->link;
C. for(iter =NULL; iter != NULL; iter = iter->link)
D. for(iter = head; iter != NULL; iter = iter->link)

Answer 17

D. for(iter = head; iter != NULL; iter = iter->link)

Question 18

__________ is to create an instance and initialize data meme era of a struct data type

Answer 18

Constructor

Question 19

The name of a constructor of a struct data type named Employee is ____________

Answer 19

Employee

Question 20

The return of a construct of a struct data type named Employee is __________

Answer 20

none

Question 21

The constructor of a struct data type named Employee without parameter variables is called _______________

Answer 21

Default constructor

Question 22

Can a struct data type have multiple constructors ?

Answer 22

Yes

Question 23

Explain why a struct data type have multiple constructors

Answer 23

Constructors are member functions. A function can be overloaded

Question 24

How do you identify which constructor of a struct data type is called when an instance of the type is created?

Answer 24

Node* p1 = new node;
Node* p2 = new node(e);

Node(EMP);

Question 25

Write a code that creates an instance of Employee at run time (, or dynamically), assign a salary to the instance, and display it on the console

Answer 25

Employee* p = new Employee; p->salary = 1000; cout << p->salary << endl; delete p;

Question 26

What is the advantage and disadvantage of using an array compared to using a singly linked list when storing a collection of data items?

Answer 26

Array size is fixed when allocated Disadvantages - if array is full and more data items are needed, you have to resize the array, allocate new array, copy items from existing array one at a time, and delete existing array. Advantages - using pointer arithmetic to access next or previous item.

Question 27

When you define a default constructor of Employee type outside the declaration of Employee type, you write __________ as the header of the function.

Answer 27

Employee::Employee();

Question 28

You have main.cpp to compile on the CS server. What is a command to compile the program?

Answer 28

g++ main.cpp

Question 29

What is the command to list all the files and directories of the current directory you are in?

Answer 29

ls -al

Question 30

WinSCP is a program that ______________

Answer 30

Transfers files from local comp to server

Question 31

Putty is a program that ____________

Answer 31

Emulates a terminal of a remote server

Question 32

What is the keyword to use to define a class named DB?

Answer 32

class

Question 33

Can a class data type include variables?

Answer 33

Yes

Question 34

Can a class data type include functions?

Answer 34

Yes

Question 35

Variables declared in a class data type are called _____

Answer 35

Data members

Question 36

Functions declared in a class data type are called _______

Answer 36

Member function

Question 37

A member function of a class whose name is the same as that of the class called ________

Answer 37

Constructor

Question 38

A variable whose type is a class is called _______

Answer 38

Class variable

Question 39

The name of a constructor of a class data type named DB is _______

Answer 39

DB()

Question 40

The return of a constructor of a class data type named DB is ______

Answer 40

None

Question 41

The constructor of a class data type named DB without parameter variable is called.

Answer 41

Default constructor

Question 42

When a class do not define its constructor, the compiler creates __________. In this case, the values of the data members of the object.

Answer 42

Default constructor

Question 43

When an object of a class is created, what will be the values of the data members of the object?

Answer 43

Depends on which constructor is called to create that object. If the constructor called did not initialize member variables, the data members have garbage values

Question 44

________ allows multiple functions or member functions of a class to use the same function name as long as their _______ are different.

Answer 44

Function overloading, signatures

Question 45

The signature of a function in C++ is uniquely determine by ______ , ______ , and ______. Return type may be/may not be part of the signature of a function, depending on what compiler is used.

Answer 45

Function name, # of parameter variables, data type of each parameter variable in order

Question 46

A variable that is declared within a function, whether it is regular or a member of a class/struct is _______ to the _______ and the memory that is occupied by the variable is deleted when ______.

Answer 46

Local, function, the function returns

Question 47

In each do the following code, write the prototype of a constructor that is called and complete each line. new DB; new DB(10);

Answer 47

new DB; DB(); new DB; DB(int);

Question 48

What is the difference between a struct and a class in C++?

Answer 48

Class members Default to private but can be declared private or public. Struct members default to public.

Question 49

The keyword, private and public, in the class declaration are called ________

Answer 49

Access specifiers

Question 50

What is the difference between private members and public members

Answer 50

The functions that are not a member of the class can not directly access private members. A public member is accessible from anywhere outside the class

Question 51

In the following code segment, what will be stored in the stack and in the heap of the program respectively? ``` int main() { double x; int *p = new int; int* q = new int[3]; } ```

Answer 51

x, *p, *q - stack int, int[3] - heap

Question 52

What will be the printed values of x and y? void increaseByOne(int* &, double*); ``` int main()  {      int x;     double y;     int* p = &x;      double* q = &y;     *p = 3;     *q = 3.14;          increaseByOne(p, q);
 cout << x << " " << y << endl; cout << p << " " << q << endl; return 0; } ``` ``` void increaseByOne(int* &p1, double* q1) { (*p1)++; (*q1)++; p1++; q1++; } ```

Answer 52

``` x = 4 y = 4.14 ```

Question 53

Will the value of p be increased after increasedByOne() returns? Why / why not? void increaseByOne(int* &, double*); ``` int main()  {      int x;     double y;     int* p = &x;      double* q = &y;     *p = 3;     *q = 3.14;          increaseByOne(p, q);
 cout << x << " " << y << endl; cout << p << " " << q << endl; return 0; } ``` ``` void increaseByOne(int* &p1, double* q1) { (*p1)++; (*q1)++; p1++; q1++; } ```

Answer 53

The value of p will increase because the parameter data type in the function is a reference of a pointer that increments arithmetically.

Question 54

Will the value of q be increased after increasebyOne() returns? Why / why not ? void increaseByOne(int* &, double*); ``` int main()  {      int x;     double y;     int* p = &x;      double* q = &y;     *p = 3;     *q = 3.14;          increaseByOne(p, q);
 cout << x << " " << y << endl; cout << p << " " << q << endl; return 0; } ``` ``` void increaseByOne(int* &p1, double* q1) { (*p1)++; (*q1)++; p1++; q1++; } ```

Answer 54

No,

Question 55

5. What is wrong with the following code? Fix all the errors. int p=int new; 
delete[] p;

Answer 55

int* p = new int; 
delete p; OR int * p = new int[5]; delete p[];

Question 56

Write a code that generates random integers from 10 to 20.

Answer 56

``` #include #include ``` srand(time(0)); int = x; x = rand() % 11 + 10;

Question 57

In the following code segment, what will be stored in the stack area of the program? int* m[3];

Answer 57

m[3];

Question 58

In the following code segment, what will be stored in the heap area of the program? 
int* m[3];
for(int i = 0; i < 3; i++) m[i] = new int[4];

Answer 58

int[4]

Question 59

What is wrong with the following code segment? Fix the error. int* m[3]; 
for(int i = 0; i < 3; i++) m[i] = new int[4]; 
 delete [] m;

Answer 59

int* m = new int[3]; for(int i = 0; i < 3; i++) m[i]; delete [] m;

Question 60

Write a code that initializes a pointer variable pointing to an integer.

Answer 60

Int *p = &x;

Question 61

What will be a problem with the following code segment? Fix the error(s). const int SIZE = 5; double * p = new int[SIZE]; for(int i = 0; o <= SIZE; i++) cout << (p + i) << endl;

Answer 61

const int SIZE = 5; int * p = new int[SIZE]; for(int i = 0; i <= SIZE; i++) cout << p[i] << endl;