CMSC 131 (Loops/Arrays/Classes)
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1. Write a for loop and a while loop that print the even numbers from 
   0 up to (including ) an specified maximum value.

2. Write a do while that computes the sum of the square roots from 1 up
   to a specified maximum value.

3. Write a nested while loop pair that generates the following triangular 
   set of * for a particular number of rows.  For example, for five rows 
   we will have:

   *
   **
   ***
   ****
   ******

4. Write a nested do while pair that generates the multiplication table
   for an specified maximum value.  For example, for a value of 3 we will
   have:

   0 0 0 0
   0 1 2 3
   0 2 4 6
   0 3 6 9

   You can assume the table will have a minimum size of one row and
   one column.

5. Write a piece of code that computes the factorial.  The definition
   of N factorial is:

   N! -> N * (N - 1)!
  
6. Write a piece of code that determines whether two arrays of doubles
   have the same elements.  For example, given the following arrays:

   int[] a = {1.0, 4.5, 8.9, 10.0};
   int[] b = {4.5, 1.0, 10.0, 8.9};
   int[] c = {1.0, 4.5};

   we can see that a and b are the only arrays that have the same
   elements.

7. Write a piece of code that determines whether the elements of an
   array are contained in a second array.  For example, given the 
   following two arrays:

   int[] a = {10, 20};
   int[] b = {5, 7, 20, 3, 10};

   we can see that all the elements of a are present in b.

8. Write a piece of code that appends the contents of one array to
   to the end of another.  A new array (with a length corresponding to
   sum of the lengths of the originals arrays) should be created.

9. Write a piece of code that given an array creates a new array 
   where each element with index k corresponds to the sum of elements from 
   the original array starting at index 0 up to index k.  For example, 
   given the following array:

   int[] a = {10, 4, 12, 6};
 
   the new array will have the elements:

   {10, 14, 26, 32}

10. Write a Java class named RandomValuesArray that satisfies the
    following specifications:

    a. A constructor with the signature:
	 RandomValuesArray(int maxElements, int maxRandomValue)

       which creates an array of size maxElements and initializes it with
       random values from 0 up to (including) maxRandomValue.

    b. Define the necessary instance variables associated with the class.

    c. A public method called reInitialized which updates the set of 
       random values in the array.

    d. A public method toString that allow us to print the contents of the
       array.

    e. A public method getMaximum returning the maximum value in the array.

    f. A public method getNumberEven returning the number of even values
       in the array.

    g. A main method that creates an instance of the RandomValuesArray
       class and uses the methods defined above. 

11. Write a Java class named Student that allow us to manipulate a student's
    record.  The following are the specifications associated with the
    class:

    a. A constructor with the signature:

       Student(String theName, double[] theScores)

       which keeps track of a set of scores passed in.

    b. Define the necessary instance variables associated with the class.

    c. A public method called getNumeric grade that returns the numeric
       grade associated with the student.  

    d. A public method called getLetterGrade with the following signature:

       char getLetterGrade(double[] theCutoffs)

       The method will return a letter grade based on the cutoffs provided.
       For example, the cutoffs array could have the following values:

       90, 80, 70, 60

       Based on this values a numeric grade of 92 will return an A.

    e. An appropriate toString() method for the class.

    f. A main method that creates an instance of the Student class and
       uses the methods defined above. 

12. For this exercise you will use the Student class you previously
    developed.  Write a class named Section representing a college
    course section.  The specifications associated with the class are:

    a. A constructor with the signature:

	 public Section(String theCourseName, int theMaxSize)

       which will create an array of Student objects.

    b. Define the necessary instance variables associated with the class.

    c. A method called addStudent which will add a Student object to
       the next available entry in the array.  The signature of the
       method will be:

       public void addStudent(Student theStudent)

    d. A method called removeStudent that will remove a Student object
      by setting the array entry corresponding to the student to null.

    e. The appropriate toString() for the class.


 13. Design Problem

     In the above exercises there were references to a Section and Student
    class. For this problem we want you to think about the set of classes
    necessary to fully implement a registration system.  The following
    issues must be taken into account:

    a. A school has several sections for a course.
    b. Each section has a professor assigned to it.
    c. The school has several courses.
    d. A professor can teach different courses and different sections
       of a course.
    e. A student can be registered in different courses at the same time.
    f. A course can have one or more TAs assigned to it.
    g. Each section must be assigned a room.
    h. Students add and drop courses and change sections.
    i. Students must be billed for the course they are taking.

    Come up with a design (by defining the necessary classes) that allow
    us to deal with the specifications provided above.  Feel free to 
    add any data members and methods you think are necessary.  Make sure
    you specify any assumptions you make in your design.  Remember, you 
    don't need to implement the code; just specify which classes are
    needed, which methods each class should have, and the data members
    associated with each class.