Goa Board Class 12 Question Paper 2024 Computer Science

2024 III 09 0930 Seat No.

Time : 3 Hours COMPUTER SCIENCE
Subject Code

H 4 7 0 5

Total No. of Questions : 35 (Printed Pages : 15) Maximum Marks : 70

INSTRUCTIONS : (i) All questions are compulsory, however there is an
internal choice for question number 31, 32, 34 and 35.

(ii) Question number 1 to 7 should be attempted only once.

(iii) Programs should be written in C++ only.

(iv) State your assumptions clearly :

Section A : Consists of 14 questions of 1 mark each.

Section B : Consists of 10 questions of 2 marks each.

Section C : Consists of 8 questions of 3 marks each.

Section D : Consists of 3 questions of 4 marks each.

SECTION – ‘A’

1. Write the CORRECT alternative from those given below : 1

What will be the value of ‘‘a’’ after evaluating the following C++ arithmetic
expression ?

int a = 4 + 4*2/5 + 20;

• 20

• 23

• 24

• 25
H-4705 1 P.T.O.

2. Write the CORRECT alternative from those given below : 1

While evaluating a postfix expression, consider that the current status of the
stack is top 5, 4, 6, 6. At this point if operator ‘–’ is encountered in the
postfix expression, then which of the following step needs to be performed ?

• – is pushed into the stack

• 5 – 4 = 1 is pushed on to the stack

• 4 – 5 = – 1 is pushed on to the stack

• 6 – 6 = 0 is pushed on to the stack

3. Write the CORRECT alternative from those given below : 1

Which of the following algorithm sorts the list by swapping the entries
whenever pair of adjacent keys are out of desired order ?

• Insertion sort

• Selection sort

• Bubble sort

• Merge sort

4. Write the CORRECT alternative from those given below : 1

If we are opening a file using an object of ofstream class, then default mode/
modes of opening the file is ......................... .

• ios::app

• ios::out

• ios::in|ios::trunc

• ios::out|ios::trunc

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5. Write the CORRECT alternative from those given below : 1

The complement of A BC is ............................

• A B C

• ABC

• A (B C)

• A BC

6. Write the CORRECT alternative from those given below : 1

Which of the following is a valid IP address ?

• 678.13.765.78

• 197.185.345.12

• 1.999.231.210

• 0.196.45.0

7. Write the CORRECT alternative from those given below : 1

Which of the following is not a transmission medium ?

• Telephone lines

• Coaxial cable

• Modem

• Microwave

H-4705 3 P.T.O.

8. What is function overloading ? 1

9. Define the term data encapsulation in the context of OOPs. 1

10. Which data structure follows FIFO mechanism ? 1

11. Name the stream used for reading only from a file. 1

12. What is a logic gate ? 1

13. What is a repeater in context to Computer networks ? 1

14. Name the protocol that enables files to be transferred between computers. 1

SECTION – ‘B’

15. Consider the following class declaration and answer the questions given
below it : 2

class JOB

{

int jobid;

char jobtype;

public:

~JOB() {cout<<’’Resigned’’;} //Function 1

JOB(int x, char y) { jobid=x; jobtype=y;} //Function 2

};

(i) What is function 1 called in context to OOPS ? When does it get
invoked ?

(ii) What is function 2 called in context to OOPS ? Write a statement
in C++ to invoke function 2.

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16. Determine the output of the following C++ program : 2

int a=18;

void trial(int &x, int z=15)

{

x %=z;

z –=5;

}

int main()

{

int a=5;

trial(::a);

cout<<::a<<" : "<<a<<endl;

trial(a,::a);

cout<<::a<<" : "<<a<<endl;

}

17. State TWO points of difference between singly linked list and doubly linked

list. 2

18. Sort the following numbers in ascending order using selection sort and show

the contents of the array at the end of each pass : 2

52, 22, 89, 96, 34

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19. Assuming that ‘‘fin’’ is the input file stream object and ‘‘fout’’ is the output

file stream object, answer the following questions : 2

(i) Write a C++ statement to move the get pointer forward by 25 bytes

from the current position in the file.

(ii) Write a C++ statement to move the put pointer backward by 10 bytes

from the end of the file.

20. Assuming that ‘‘data.txt’’ is an already existing text file, write a function

COUNT() in C++ to count and return the number of capital letters present

in the text file. 2

21. Obtain the simplified Boolean expression for the following logic circuit

diagram : 2

22. Write a short note on Packet switching. 2

23. Draw a diagram to show how five computers can be connected in STAR topology.

Also write ONE advantage and ONE disadvantage of STAR topology. 2

24. State any TWO points of difference between LAN and WAN. 2

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SECTION – ‘C’

25. Simplify the following Boolean expression in POS form and draw the logic

circuit diagram for the simplified expression using NOR gates only : 3

F(A, B, C) = (4, 5, 7)

26. Define a class ‘‘Tourist’’ in C++ with the following specification : 3

Private Data members :

• Cno – type integer, to store cab number

• Ctype – to store character ‘A’, ‘B’ or ‘C’ as city type

• Perkm – type float, to store per kilo meter charges

• Distance – type float, to store distance travelled in kilometers

• Amount – of type float, to be calculated as Perkm × Distance

• Assign() – to assign the data member Perkm as per the following table :

Ctype Perkm

A 20

B 18

C 15

Public member function :

• readdata() – to allow user to enter Cno, Ctype and Distance, and also

call the function Assign() to assign the data member Perkm.

• displaydata() – to calculate the Amount and display all the data

members on the screen.

H-4705 7 P.T.O.

27. Consider the following class declarations and answer the question (i) to (iv)
based on the same : 3

class EXTERIOR

{

int ordered;

char address[20];

protected :

foat advance;

public:

EXTERIOR();

void book();

void show();

};

class PAINT : public EXTERIOR

{

int wallarea, colorcode;

protected:

char type;

public :

PAINT();

void Pbook();

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};

class BILL : public PAINT

{

float charges;

void calculate();

public:

BILL();

void Billing();

};

(i) Which type of inheritance is shown above ?

(ii) Write the names of all the members, which are directly accessible from
the member functions of class PAINT.

(iii) Write the names of all the member functions, which are directly
accessible from an object of class BILL.

(iv) What will be the order of execution of constructors, when an object of
class BILL is declared ?

28. Convert the following infix expression to its equivalent postfix expression and
show the stack content after every step : 3

A/(B + C)* D – E

29. Obtain simplified SOP Boolean expression for the following expression using
K-map and draw the logic circuit diagram for the simplified expression using
NAND gates only : 3

F(A, B, C, D) ABCD BCD ACD BCD CD

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30. Complete the following function definition to check and return 1 if matrix

A of order n × n is a skew symmetric matrix or 0 otherwise. 3

int IS_SKEWSYM(int A[][50], int n)

{

-----------------

-----------------

}

Note : A square matrix is said to be skew symmetric if it is equal to the

negative of its transpose matrix.

0 1 2
For example 1 0 3 is skew symmetric matrix.
2 3 0

31. Write a complete procedural C++ program to check if a given number is a

neon number or not. 3

For example : Original Number = 9

Square of 9 = 81

Sum of 81 = 8 + 1 = 9 = original number.

Therefore 9 is a neon number.

OR

Write a complete procedural C++ program to convert a given binary number

N (of type integer) to its equivalent decimal number.

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32. Assuming that A is an 1-D array containing ‘n’ integers in ascending order,

write a function in C++ to remove duplicate values present in the array. 3

For example :

If original array is

The output array should be

OR

Complete the following function definition to find array C such that
C = A – B (set difference) i.e. C should contain elements of A which are not
present in B.

void setdifference (int A[], int m, int B[], int n)

{

.............................

.............................

}

For example :

If A is

And B is

The C should have

H-4705 11 P.T.O.

SECTION – ‘D’

33. Declare an abstract class named STUDENT with the following members :

(i) rollno-of type integer under private visibility label 4

(ii) Parameterised constructor which will only initialise the data member

rollno.

(iii) Show() – A function under protected visibility to display the data

member rollno.

Declare another abstract class named TEACHER with the following members –

(i) tcode (teacher code) – of type integer under private visibility label

(ii) Parameterised constructor which will only initialise the data member

tcode

(iii) show() – A function under protected vbisibility to display the data

member tcode.

Derive a class COURSE from class STUDENT and class TEACHER both in

public mode. The class should have the following members :

(i) ccode (Course code) – of type integer under private visibility label

(ii) A parameterised constructor which will only initialise the data member

ccode.

(iii) show() – A function under public visibility to display the data member

ccode.

Write main() function to create an object of type COURSE and display data

member of all the classes.

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34. Assuming that voters.dat is an already existing binary file consisting of
objects of the following class type. 4

class VOTERS

{

int voterid;

char name[30];

char geneder, /*where gender is M for male, F for female and O for
others */ public :

void getdata(); //function to read the data members

void showdata(); //function to display the data members

char getgender() {return gender;}

};

Write a function in C++ to copy the details of all male voters from voters.dat
file to a new binary file called male.dat and also copy details of all female
voters from voters.dat file to another new binary file called female.dat.

OR

Consider the following class declaration :

class VOLUNTEERS

{

char name[30], city[20];

int age;

public:

H-4705 13 P.T.O.

void indata(); //function to read the data members

void outdata(); //function to display the data members

int getage()

{return(age);}

};

Assuming that ‘‘north.dat’’ contains details of volunteers from North Goa &
‘‘south.dat’’ contains details of volunteers from South Goa, write a C++
function to transfer the details of all volunteers from ‘‘north.dat’’ whose age
lies in the range from 18 to 25 to a new binary file called ‘‘collect.dat’’.
Append the details of all volundeers in the given range of age from south.dat
to the binary file collect.dat.

35. Consider the following class declaration : 4

class LIST

{

struct node

{

int rno;

float score;

node *link;

}* start;

public:

LIST() {start=NULL;}

void create(); //creates linked list of n nodes

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void insert();

};

Write a function definition for insert() to insert a node at position
P(1 P n 1) in the linked list.
OR
Consider the following class declaration :
class LIST
{
struct node
{
int itemno;
char name[30];
node *link;
}*start;
public:
LIST() {start=NULL;}
void create(); //creates linked list of n nodes
void remove();
};
Write a function definition for remove() to delete a node at position
P(1 P n) from the linked list.

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