XII CBSE Previous Year Question Paper

1
XII CBSE Previous Year Question Paper

• QUESTION NO
• 2 (a)
• 2 Marks

2
2. (a) Define Multilevel and Multiple inheritance
in context of Object Oriented Programming. Give
suitable example to illustrate the
same. Delhi 2006 2
2. (a) In Multilevel inheritance, a class
inherits its properties from another derived
class transitively.
A
B
C
3
In Multiple inheritance, a derived class inherits
from multiple base classes. (1/2 mark each
for any correct definition) (1/2 mark each for
any correct example diagrammatic/ C
representation) OR (Full 2 marks for explaining
the 2 types of inheritance with the help of
suitable examples or diagram)
B
A
C
4
2. (a) What is this pointer ? Give an example
to illustrate the use of it in C. Outside
Delhi 2006 2
2. (a) Students are exposed to the concept of
pointers, but not exposed specifically to the
concept of this pointer. So benefit of doubt
should be given to the students. (Full 2 marks
to be given to students who have correctly
attempted for at least 1 mark in the entire Q.
No. 2 (a) to 2 (d))
5
2. (a) Differentiate between Protected and
Private members of a class in context of
Inheritance using C. Delhi 2007 2
6
2. (a) Differentiate between Constructor and
Destructor function in context of Classes and
Objects using C OD 2007 2

• 2. (a) Constructors
• Name of the constructor functions is same as
  the name of the class
• No return type required for constructor
  function.
• Constructor functions are called automatically
  at the time of creation of the object
• Constructors can be overloaded
• Constructor functions are defined in public.

7
2. (a) Differentiate between Constructor and
Destructor function in context of Classes and
Objects using C OD 2007 2

• 2. Destructors
• Name of the destructor is same as the name of
  the class preceded by
• No return type required for destructor
  function.
• Destructor functions are called automatically
  when the scope of the object gets over
• Destructor can not be overloaded
• Destructor function is defined in public.

8
2. (a) Differentiate between Constructor and
Destructor function in context of Classes and
Objects using C OD 2007 2
(1 Mark for correct explanation of
Constructor) (1 Mark for correct explanation of
Destructor) OR (1 Mark for any valid example of a
Constructor) (1 Mark for any valid example of a
Destructor)
9
2. (a) Differentiate between public and private
visibility modes in context of Object Oriented
Programming using a suitable example illustrating
each. Delhi 2008 2
Ans PUBLIC VISIBILITY MODE Members of a class
declared under this visibility are accessible
inside the class (in member functions of the
class) as well as by the Objects of that
class (in any non member function of the program,
prototyped / defined after the class
declaration).
10
2. (a) Differentiate between public and private
visibility modes in context of Object Oriented
Programming using a suitable example illustrating
each. Delhi 2008 2
Ans PRIVATE VISIBILITY MODE Members of a class
declared under this visibility are accessible
only inside the class (in member functions of the
class). They can not be accessed outside the
class. class Example int Priv
11
2. (a) Differentiate between public and private
visibility modes in context of Object Oriented
Programming using a suitable example illustrating
each. Delhi 2008 2
void Assign ( ) Priv 10 //private member
accessible only inside class void main (
) Example E E.Assign( ) //public member
accessible by Object
12
2. (a) Differentiate between public and private
visibility modes in context of Object Oriented
Programming using a suitable example illustrating
each. Delhi 2008 2
(2 Marks for differentiating public and private
correctly using suitable example) OR (1 Mark for
correct explanation of private visibility) (1
Mark for correct explanation of public
visibility) OR (1 Mark for any valid example of a
private member of a class) (1 Mark for any valid
example of a public member of a class)
13
Outside Delhi 2008 2
14
2. (a) What is copy constructor? Give an example
in C to illustrate copy constructor.
Delhi 2009 2
Ans A copy constructor is an overloaded
constructor function in which (an) object(s) of
the same class is/are passed as a reference
parameter(s). It is used when an objects data
value is related to or is initialised using
another objects data value of the same class. In
the example below the values of data members of
object Q are dependent on the values of data
members of object P and Data members of object R
dependent on Q.
15
//Example of Copy Constructor class Play int
Count, Number public Play() //constructor Play(
Play )//copy constructor void Disp() void
Change(int,int) PlayPlay ()
//constructor Count0 Number0
16
Play Play (Play P) //copy constructor CountP
.Countl0 NumberP.Number20 void
PlayDisp() coutltltCount coutltltNumberltltendl
void PlayChange(int C,int N) CountC NumberN

17
void main () Play P //Call for
constructor P.Disp () P.Change(90,80) Play
Q(P) //Copy constructor call Q.Disp() Play RQ
//Copy constructor ca11 same as P1ay R(Q) R.
Disp() (1 Mark for correct explanation of Copy
Constructor) (1 Mark for a valid example of Copy
Constructor) Note Member function other than the
constructors are optional
18
2. (a) What is function overloading? Give an
example in C to illustrate function
overloading. Outside Delhi 2
Ans Function overloading is an example of
polymorphism, where the functions having same
name with different set of parameters perform
different operations. OR When a function is
having more than one definition and
differentiable by the number/type of parameters
is known as function overloading.
19
2. (a) What is function overloading? Give an
example in C to illustrate function
overloading. Outside Delhi 2
Example void Disp() //Function
1 coutltltHelloltltendl void Disp(int N) //
Function 2 for (int I1IltNI) coutltltIltltend1

20
2. (a) What is function overloading? Give an
example in C to illustrate function
overloading. Outside Delhi 2
(1 Mark for correct definition or explanation of
Function Overloading) (1 Mark for a valid example
of Function Overloading)
21
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . Delhi 2010 2
Ans. The process of using an -operator or a
function in different ways for different set of
inputs given is known- as polymorphism. Function
overloading is- an example of polymorphism, where
the functions having same name with different set
of parameters perform different operations.
22
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . Delhi 2010 2
Example void Disp ( ) //Function
1 coutltltHelloltltendl void Disp(int N)
//Function 2 for(int I1IltNI) coutltltIltltendl

23
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . Delhi 2010 2
void Disp (int N,int M) //Function 3 for (int
INIltM I) coutltltNltltxltltIltltltltNIltltendl
void main ( ) int x5, y10 Disp(x)
//Function 2 called-Prints numbers from 1 to 5
24
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . Delhi 2010 2
Disp(x,y) //Function 3 called- Prints from
multiples of 5 ranging from 5 to 10 Disp ()
//Function 1 called- Prints Hello (1 Mark for
correct explanation of Polymorphism) (1 Mark for
a valid example of Polymorphism)
25
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both. Outside
Delhi 2010 2
Ans. Data Encapsulation Wrapping up of data and
functions together in a single unit is known as
Data Encapsulation. In a class, we wrap up the
data and functions together in a single
unit. Data Hiding Keeping the data in
private/protected visibility mode of the class to
prevent it from accidental change is known as
Data Hiding.
26
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both. Outside
Delhi 2010 2
class Computer char CPUlO int RNM //Data
Hiding public //Data Encapeulation void
STOCK() void SHOW()
27
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both. Outside
Delhi 2010 2
(½ Mark for each correct explanation of Data
Encapsulation and Data Hiding) (½ Marks for each
correct example of Data Encapsulation and Data
Hiding) OR (2 Marks for explaining the concept of
the terms through suitable examples) OR (Only 1
Mark to be awarded for Explanation given without
any example)
28
2. (a) Differentiate between members, which are
present within the private visibility mode with
those which are present within the public
visibility modes. Delhi 2011 2
Ans Private members of a class are accessible
only to the member functions of the same
class. Public members of a class are accessible
to the member functions of the same class as well
as member functions of its derived class(es) and
also to an object of the class.
29
2. (a) Differentiate between members, which are
present within the private visibility mode with
those which are present within the public
visibility modes. Delhi 2011 2
class Base int N public void Assign
() N10
30
2. (a) Differentiate between members, which are
present within the private visibility mode with
those which are present within the public
visibility modes. Delhi 2011 2
class Derived public Base int X public void
DisplayBase() coutltltN //Not Accessible Assign
( ) //Accessible
31
2. (a) Differentiate between members, which are
present within the private visibility mode with
those which are present within the public
visibility modes. Delhi 2011 2
void main ( ) Base B B.Assign( )
//Accessible (1 Mark for correct explanation OR
example illustrating non accessibility of Private
Members inside Derived class) (1 Marks for
correct explanation OR example illustrating
accessibility of Public Members inside Derived
Class and to object of the class)
32
Outside Delhi 2011
33
Outside Delhi 2011
34
SAMPLE PAPER SET I 2012
35
SAMPLE PAPER SET II 2012
36
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both. Outside
Delhi 2010 SAMPLE PAPER 2009 SET I 2
Ans. Data Encapsulation Wrapping up of data and
functions together in a single unit is known as
Data Encapsulation. In a class, we wrap up the
data and functions together in a single
unit. Data Hiding Keeping the data in
private/protected visibility mode of the class to
prevent it from accidental change is known as
Data Hiding.
37
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both. Outside
Delhi 2010 SAMPLE PAPER 2009 SET I 2
class Computer char CPUlO int RNM //Data
Hiding public //Data Encapeulation void
STOCK() void SHOW()
38
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both. Outside
Delhi 2010 SAMPLE PAPER 2009 SET I 2
(½ Mark for each correct explanation of Data
Encapsulation and Data Hiding) (½ Marie for each
correct example of Data Encapsulation and Data
Hiding) OR (2 Marks for explaining the concept of
the terms through suitable examples) OR (Only 1
Mark to be awarded for Explanation given without
any example)
39
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . SAMPLE PAPER 2009 SET II ,Delhi 2010 2
Ans. The process of using an -operator or a
function in different ways for different set of
inputs given is known- as polymorphism. Function
overloading is- an example of polymorphism, where
the functions having same name with different set
of parameters perform different operations.
40
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . SAMPLE PAPER 2009 SET II Delhi 2010 2
Example void Disp ( ) //Function
1 coutltltHelloltltendl void Disp(int N)
//Function 2 for(int I1IltNI) coutltltIltltendl

41
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . Delhi 2010 2
void Disp (int N,int M) //Function 3 for (int
INIltM I) coutltltNltltxltltIltltltltNIltltendl
void main ( ) int x5, y10 Disp(x)
//Function 2 called-Prints numbers from 1 to 5
42
2. (a) What do you understand by Polymorphism.?
Also, give an example in C to illustrate the
same. . SAMPLE PAPER 2009 SET II, Delhi 2010 2
Disp(x,y) //Function 3 called- Prints from
multiples of 5 ranging from 5 to 10 Disp ()
//Function 1 called- Prints Hello (1 Mark for
correct explanation of Polymorphism) (1 Mark for
a valid example of Polymorphism)
43
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both.
2 Outside Delhi 2010, SAMPLE PAPER 2009 SET I,
SAMPLE PAPER 2010 SET I
Ans. Data Encapsulation Wrapping up of data and
functions together in a single unit is known as
Data Encapsulation. In a class, we wrap up the
data and functions together in a single
unit. Data Hiding Keeping the data in
private/protected visibility mode of the class to
prevent it from accidental change is known as
Data Hiding.
44
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both.
2 Outside Delhi 2010, SAMPLE PAPER 2009 SET I,
SAMPLE PAPER 2010 SET I
class Computer char CPUlO int RNM //Data
Hiding public //Data Encapeulation void
STOCK() void SHOW()
45
2. (a) What do you understand by Data
Encapsulation and Data Hiding ? Also, give an
example in C to illustrate both.
2 Outside Delhi 2010, SAMPLE PAPER 2009 SET I,
SAMPLE PAPER 2010 SET I
(½ Mark for each correct explanation of Data
Encapsulation and Data Hiding) (½ Marie for each
correct example of Data Encapsulation and Data
Hiding) OR (2 Marks for explaining the concept of
the terms through suitable examples) OR (Only 1
Mark to be awarded for Explanation given without
any example)
46

• THANK YOU