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CBSE AISSCE 2016-2017 Marking Scheme for Computer Science
(Sub Code: 083 Paper Code 91/1 Delhi)

2 (a) List four characteristics of Object Oriented programming. 2
Ans Encapsulation
Data Hiding
Abstraction
Inheritance
Polymorphism

( ½ mark for each characteristic upto four characteristics)
(b) class Test: 2
rollno=1

marks=75
def __init__(self,r,m): #function 1
self.rollno=r
self.marks=m
def assign(self,r,m): #function 2
rollno = n
marks = m

def check(self): #function 3
print self.rollno,self.marks
print rollno,marks
(i) In the above class definition, both the functions - function 1 as well as function
2 have similar definition. How are they different in execution?
(ii) Write statements to execute function 1 and function 2.
Ans i) Function 1 is the constructor which gets executed automatically as soon as
the object of the class is created. Function 2 is a member function which has
to be called to assign the values to rollno and marks.

ii) Function 1 ​E1=Test(1,95) # Any values in the parameter
Function 2 ​E1.assign(1,95) # Any values in the parameter

(1 mark for correct difference)
( ½ mark for each statement for executing Function 1 and function 2)

(c) Define a class RING in Python with following specifications 4
Instance Attributes
- RingID # Numeric value with a default value 101
- Radius # Numeric value with a default value 10
- Area # Numeric value
Methods:
- AreaCal() # Method to calculate Area as
# 3.14*Radius*Radius
- NewRing() # Method to allow user to enter values of
# RingID and Radius. It should also
# Call AreaCal Method
- ViewRing() # Method to display all the Attributes

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