Page 481 - Computer science 868 Class 12
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Class name                            :  Grade
                        Data Members
                        avg                                   :   double type variable to store average marks
                        grade                                 :   character variable to store grade
                        Member Functions
                        Grade (....)                          :  parameterised constructor to assign  values to data members of both
                                                                 classes
                        void calculate()                      :   calculates the average marks obtained as
                                                                 (marks [0] + marks [1] + marks [2] + marks [3] + marks [4])/5
                                                                 Grade is calculated on average marks as follows:
                                                                         Average marks                  Grade
                                                                           90 to 100                      A
                                                                            89 to 75                      B
                                                                            74 to 60                      C
                                                                            59 to 40                      D
                                                                           Below 40                       E
                        void display()                        :   displays the student's details, average marks obtained along with grades
                        Using  the concept of inheritance,  specify  the  class  Grade  giving  details  of  the  constructor  and  the  member  functions void
                       calculate() and void display(). Base class and main method need not to be written.
                    3.  A base class Array2D is defined to store numbers in a 3 × 3 matrix. A derived class Transpose is defined to generate the transpose
                       of matrix a[][]. The transpose of a matrix is obtained by interchanging its rows into columns or columns into rows:
                       Eg. if matrix a[][] is

                                                                 1     2     3
                                                                 4     5     6
                                                                 7     8     9


                        then its transpose b[][] will be
                                                                 1     4     7
                                                                 2     5     8
                                                                 3     6     9
                        Some of the members of the class are given below.
                        Class name                            :   Array2D
                        Data Members/Instance variables
                        a[][]                                 :   integer two dimensional matrix
                        Methods/Member Functions
                        Array2D(int c[][])                    :  Initialises matrix a[][]
                        void print()                          :   Prints matrix a[][]

                        Class name                            :  Transpose
                        Data Members/Instance variables
                        b[][]                                 :   integer matrix to store the transpose of a[][]
                        Methods/Member Functions
                        Transpose(.....)                      :   Initialises data members of base and derived classes
                        void generate()                       :   Generates the transpose matrix and stores it in b[][]
                        void print()                          :   Prints both the original and transpose matrices
                        Using the concept of inheritance, specify the class Transpose giving details of the constructor and the member functions void
                       generate() and void print(). Base class and main method need not to be written.






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