CS 140
Practice problems on Classes

Here are some practice programming problems using classes and objects.

These are not to be handed in, though you should feel free to ask questions about any of them outside of class. Remember that programming is an activity that you learn by doing.

1. Make a program containing class Student. This class should have two instance variables: name and age. The constructor takes a name argument and uses it to initialize the name instance variable; it also initializes the age instance variable to 18. The class has a SetAge method that can set the age to any other value. Finally, the class has a Print method. Here is a main() method for your program:
        def main():
             x = Student( "bob" )
             x.SetAge(23)
             x.Print()
2. Give class Student an instance variable Gender, which can be "M" or "F". Modfiy the constructor for Student to take a gender argument as well as a name argument to give a value to this variable.
3. Give the Student class another instance variable: transcript. This is a list of pairs, where the first element of the pair is the name of a course, and the second element is a numeric grade between 0 and 4.There are two additional methods:
        AddCourse(self)
   which asks the user for a course name and grade, and appends this pair onto the transcript, and
        GPA(self)
   which averages all of the grades in the transcript and returns the average. The main program
        def main():
             x = Student( "bob", "M")
             x.AddCourse( )
             x.AddCourse()
             print X.GPA()
   will cause the system to twce ask for course name and grade. If you supply the following information:
        Course name? Basketweaving
        Grade for Basketweaving? 4
        Course name? Time Wasting
        Grade for Time Wasting? 3
   then the print statement print X.GPA at the end of main() will print 3.5
4. Give class Student another instance variable Roommate. This can either have value None, or an object of class Student. Give the class a method AssignRoommate to give a value to this variable.
5. Make another class Faculty, which just has one instance variable, name. The only methods Faculty needs are a constructor and a Print method. Add to class Student an instance varialb advisor. This should be initialized to None in the Student constructor. Give student a method AssignAdvixor that assigns an advisor (a faculty member) to the student.
6. The relationship between Faculty and Student in (5) is too one-sided. Gve to Faculty an instance variable Advisees, which is a list of all of the advisees the faculty member has. Add to Faculty a method AssignAdvisee a method that will append a student to the Advisees list. If x is a Student and y is a Faculty, then x.AssignAdvisor(y) and y.AssignAdvisee(x) should do the same thing.