Difference between revisions of "CSC111 Exercises on Classes and Objects"

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(Exercise 3)
(Exercise 3)
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Go back to Bob containing a ''private'' member variable.
 
Go back to Bob containing a ''private'' member variable.
 
;Question 1
 
;Question 1
: Create 2 objects of type Bob, each containing the values 45 and 70, respectively, and save them in a list called '''L'''
+
: Create 2 objects of type Bob, each containing the values 45 and 70, respectively, and save them in a list called '''L'''.  Verify that the list contains these 2 objects.
 
<br />
 
<br />
 
; Question 2
 
; Question 2
: Change the value of the first element of the list to 10, and the value of the second one to 20.
+
: Change the value of the first element of the list to 10, and the value of the second one to 20.  Verify that the change was made.
 
<br />
 
<br />
 
;Question 3
 
;Question 3
: Create 20 objects of type Bob, each containing 1, 2, 3,... 20, respectively, and save them in a list called '''L2'''
+
: Create 20 objects of type Bob, each containing 1, 2, 3,... 20, respectively, and save them in a list called '''L2'''.  Display the contents of the list.
 
<br />
 
<br />
 
;Question 4
 
;Question 4
: Reset the values in all 20 objects in '''L2''' to 0.
+
: Reset the values in all 20 objects in '''L2''' to 0.  Verify that the reset operation was successful.
 
<br />
 
<br />
  

Revision as of 10:51, 14 April 2014

--D. Thiebaut (talk) 13:05, 13 April 2014 (EDT)


Exercise 1


class Bob:
   def __init__( self ):
        self._a = None

   def setA( self, x ):
        self._a = x

   def getA( self ):
       return self._a


Question 1
Create an object of type Bob, call it x, and set its member variable to 4
Question 2
Add 10 to the member variable of x.
Question 3
print the object contents of Object x. First by getting _a from x and printing it, then by adding a new method to Bob so that we can print objects just by passing them to print()


Exercise 2


This exercise is very similar to Exercise 1, but the definition of self._a is now self.a. Answer the same 3 questions.



Exercise 3


Go back to Bob containing a private member variable.

Question 1
Create 2 objects of type Bob, each containing the values 45 and 70, respectively, and save them in a list called L. Verify that the list contains these 2 objects.


Question 2
Change the value of the first element of the list to 10, and the value of the second one to 20. Verify that the change was made.


Question 3
Create 20 objects of type Bob, each containing 1, 2, 3,... 20, respectively, and save them in a list called L2. Display the contents of the list.


Question 4
Reset the values in all 20 objects in L2 to 0. Verify that the reset operation was successful.


Exercise 4


This exercise is very similar to Exercise 3, but we construct a new class that contains a list of objects of type Bob. Answer the same questions as in Exercise 3.