CBSE Board Class 12 Computer Science Previous Year Question Papers 2010

CBSE Board Previous Year Question Papers 2010 for Class 12 Computer Science

previous paper 2010
class 12
computer science

1. (a) Differentiate between a Logical Error and Syntax Error. Also give suitable examples
of each in C++. 2
(b) Name  the header file(s) that shall be needed  for  successful  compilation  of the
following C++ code : 1
void main( )
char Text[40];
(c) Rewrite   the   following  program   after  removing   the   syntactical   error(s),  if any.
Underline each correction. 2
#include <iostream.h>
const int Size 5;
void main()
int Array[Size];
Array = {50,40,30,20,10};
for(Ctr=0; Ctr<Size; Ctr++)

void main()
int Numbers[] = {2,4,8,10};
int *ptr = Numbers;
for (int C = 0; C<3; C++)
cout<< *ptr << “@”;
for(C = 0; C<4; C++)
for(C = 0; C<4; C++)
cout<< Numbers [C]<< “#”;
(e) Find the output of the following program : 3
void Indirect(int Temp=20)
for (int 1=10; I<=Temp; I+=5)
cout<<I<<”, “;
void Direct (int &Num)
void main()
int Number=20;
cout<< “ Number=” <<Number<<endl ;
(f) In the following C++ program what is the expected value of Myscore from Options
(i) to (iv) given below. Justify your answer. 2
void main( )
int Score[] = {25,20,34,56, 72, 63}, Myscore;
Myscore = Score[2 + random(2)];
cout<<Myscore<<endl; }
(i) 25
(ii) 34
(iii) 20
(iv) None of the above
2. (a) Differentiate  between  Protected  and  Private  members  of a  class  in context  of
Inheritance using C++. 2
(b) Answer the questions (i) and (ii) after going through the following class: 2
class Science
char   Topic[20];
int   Weightage;
Science ( )                     //Function   1
strcpy (Topic, “Optics” );
Weightage = 30;
cout<<“Topic Activated”;
~Science( )                     //Function   2
cout’<<”Topic Deactivated”;
(i) Name the specific features of class shown by Function 1 and Function 2 in the
above example.
(ii) How would Function 1 and Function 2 get executed ?91 4
(c) Define a class Travel in C++ with the description given below : 4
Private Members :
T_Code of  type string
No_of_Adults of type integer
No_of_Children of type integer
Distance of  type integer
TotalFare of type float
Public Members :
• A constructor to assign initial values as follows :
T_Code with the word “NULL”
No_of_Adults as 0
No_of_Children as 0
Distance as 0
TotalFare as 0
• A function AssignFare(   ) which calculates and assigns the value of the
data member TotalFare as follows :
For  each  Adult
Fare (Rs) For Distance (Km)
500 >=1000
300 <1000 & >=500
200 <500
For  each  Child the above Fare will be 50% of the Fare mentioned in the
above table.
For example :
If Distance is 750, No_of_Adults = 3 and No_of_Children = 2
Then TotalFare should be calculated as
               No_of_Adults * 300 + No_of_Children * 150
i.e.        3 * 300 + 2 * 150 = 1200
• A function EnterTravel( ) to input the values of the data members T_Code,
No_of_Adults, No_of_Children and Distance; and invoke the AssignFare( )
• A function ShowTravel( ) which  displays the  content  of all the  data
members for a Travel.
(d) Answer the questions (i) to (iv) based on the following code : 4
class Teacher
char TNo[5], TName[20], DeptflO];
int Workload;
float Salary;
void AssignSal(float);
Teacher( ) ;
void TEntry( ) ;
void TDisplay( );
class Student
char Admno[10], SName[20], Stream[10];
int Attendance, TotMarks;
Student( );
void SEntry( );
void SDisplay( );
class School : public Student, public  Teacher
char SCode[10], SchName[20];
School ( ) ;
void SchEntry( );
void SchDisplay( );
(i) Which type of Inheritance is depicted by the above example ?
(ii) Identify the member functiion(s) that cannot be called directly from the objects
of class School from the following :
TEntry( )
SDisplay( )
SchEntry( )
(iii) Write name of all the member(s) accessible from member functions of class
(iv) If  class School was derived privately from class Teacher and privately from
class Student, then, name the member function(s) that could be accessed
through Objects of class School.
3. (a) Write a function in C++ which accepts an integer array and its arguments
and replaces elements having even values with its half and elements having odd
values with twice its value. 4
Example : if an array of five elements initially contains the elements as
3, 4, 5, 16, 9
then the function should rearrange the content of the array as
6, 2, 10, 8, 18
(b) An array Arr[15][20] is stored in the memory along the row with each element
occupying 4 bytes. Find out the Base Address and address of the element Arr[3][2],
if the element Arr[5][2] is stored at the address 1500.
(c) Write a function in C++ to delete a node containing customer’s information, from a
dynamically   allocated   Queue   of  Customers   implemented   with  the   help of the
following structure : 4
struct Customer
int CNo;
char CName[20];
Customer *Link;
(d) Write  a  function in  C++  which accepts  a 2D  array of integers  and its  size  as
arguments and displays the elements of middle row and the elements of middle
column. 2
[Assuming the 2D Array to be a square matrix with odd dimension
i.e.  3×3, 5×5, 7×7 etc...]
Example, if the array content is
3   5  4
7   6  9
2   1  8
Output through the function should be :
Middle Row : 7  6  9
Middle Column : 5  6   1
(e) Evaluate the following postfix notation of expression : 2
15    3    2    +    /     7    +    2    *
4. (a) Observe the program segment given below carefully, and answer the question that
follows : 1
class Labrecord
int Expno;
char Experiment[20];
char Checked;
int Marks;
public :
//function to enter Experiment details
void EnterExp( );
//function to display Experiment details
void ShowExp ( ) ;
//function to return Expno
char RChecked ( ) {return Checked;}
//function to assign Marks
void Assignmarks(int M)
{     Marks = M;}
void   MpdifyMarks()
{ fstream   File;“Marks.Dat”,ios::binary|ios::in|ios::out);
Labrecord L;
int Rec = 0;
while (*)&L, sizeof(L)))
if(L.RChecked( )== ‘N‘ )
_____________________ //statement 1
_____________________ //statement 2
Rec ++ ;
File.close ();
If the funption ModifyMarks() is supposed to modify Marks for the records in the file
MARKS.DAT based on their status of the member Checked (containing value either
'Y' or ‘N’). Write C++ statements for the  statement 1  and  statement 2,  where,
statement 1  is required to position the file write pointer to an appropriate place in
the file and  statement  2 is to perform the write operation with the modified record.
(b) Write a function in C++ to print the count of the word  the  as an independent word
in a text file STORY.TXT. 2
For example, if the content of the file STORY.TXT is
There was a monkey in  the zoo.  The
monkey was very naughty.
Then the output of the program should be 2.
(c) Given a binary file SPORTS.DAT, containing records of the following structure type :
struct Sports
char   Event[20];
char   Participant[10][30];
Write a function in C++ that would read contents from the file SPORTS.DAT and
creates a file named ATHLETIC.DAT copying only those records from SPORTS.DAT
where the event name is “Athletics”. 3
5. (a) What is the importance of a Primary Key in a table ? Explain with a suitable
example. 291 8
(b) Consider the following tables Consignor and Consignee. Write SQL commands for
the statements (i) to (iv) and give outputs for SQL queries (v) to (viii). 6
CnorlD CnorName CnorAddress City
ND01 R  Singhal 24, ABC Enclave New Delhi
ND02 Amit Kumar 123, Palm Avenue New Delhi
MU15 R  Kohli 5/A, South Street Mumbai
MU50 S  Kaur 27-K, Westend Mumbai
CneelD CnorlD CneeName CneeAddress CneeCity
MU05 ND01 Rahul Kishore 5,  Park Avenue Mumbai
ND08 ND02 P  Dhingra 16/J, Moore Enclave New Delhi
KO19 MU15 A P Roy 2A, Central Avenue Kolkata
MU32 ND02 S  Mittal P  245, AB Colony Mumbai
ND48 MU50 B P Jain 13, Block D, A Vihar New Delhi
(i) To display the names of all Consignors from Mumbai.’
(ii) To  display the CneelD, CnorName, CnorAddress, CneeName, CneeAddress for
every  Consignee.
(iii) To  display consignee details in ascending order of CneeName.
(iv) To  display number of consignors from each city,
(vi) SELECT A.CnorName, B.CneeName
FROM Consignor A, Consignee B
WHERE A.CnorID = B.CnorlD AND B.CneeCity = ‘Mumbai’;
(vii) SELECT CneeName, CneeAddress
FROM Consignee
WHERE CneeCity NOT IN (‘Mumbai’, ‘Kolkata’);
(viii) SELECT CneelD, CneeName
FROM Consignee
WHERE CnorID=’MU15' OR CnorID=’ND01';
6. (a) State De Morgan’s Theorems and verify the same using truth table. 2
(b) Write the equivalent Canonical Product of Sum Expression for the following Sum of
Product Expression
F(X, Y, Z) =  (0, 2, 4, 5) 2
(c) Write the equivalent Boolean expression for the following Logic Circuit. 2
(d) Reduce the following Boolean expression using K-Map : 2
F(A, B, C, D) =  (5,6,7,8,9,12,13,14,15)
7. (a) What is the significance of Cyber Law ? 1
(b) Expand the following terms with respect to Networking : 2
(i) XML
(ii) WWW
(iii) WLL
(iv) TCP/IP
(c) Which of the following units measures the speed with which data can be
transmitted from one node to another node of a network ? Also, give the expansion
of the suggested unit. 1
(i) KMph
(ii) Mbps
(iii) MGps
(d) “Hindustan Connecting World Association” is planning to start their offices in four
major cities in India to provide regional IT infrastructure support in the field of
Education & Culture. The company has planned to set up their head office in New
Delhi in three locations and have named their New Delhi offices as “Sales Office”,
”Head Office” and “Tech Office”. The company’s regional offices are located at
”Coimbatore”, “Kolkata” and “Ahmedabad”.
A rough layout of the same is as follows :
Approximate distances between these offices as per network survey team is as
follows :
Place From Place To Distance
Head Office Sales Office 10 KM
Head Office Tech Office 70  Meter
Head Office Kolkata Office 1291 KM
Head Office Ahmedabad Office 790 KM
Head Office Coimbatore Office 1952 KM
In continuation of the  above, the company experts have planned to install the following
number of computers in each of their offices :
Head Office 100
Sales Office 20
Tech Office 50
Kolkata Office 50
Ahmedabad Office 50
Coimbatore Office 50
(i) Suggest network type (out of LAN, MAN, WAN) for connecting each of the
following set of their offices :
• Head Office and Tech Office
• Head Office and Coimbatore Office
(ii) Which device will you suggest to be procured by the company for connecting all
the computers within each of, their offices out of the following devices ?
• Modem
• Telephone
• Switch/Hub
(iii) Which of the following communication media, will you suggest to be procured
by the company for connecting their local offices in New Delhi for very effective and
fast communication ?
• Ethernet Cable
• Optical Fiber
• Telephone Cable
(iv) Suggest a cable/wiring layout for connecting the company’s local offices located
in New Delhi. Also,, suggest an effective method/technology for connecting the
company’s regional offices at “Kolkata”, “Coimbatore” and “Ahmedabad”. 4