Difference between revisions of "Advanced-C++/C2/More-On-Inheritance/English-timed"

| Welcome to the spoken tutorial on '''Multiple''' and '''Hierarchical Inheritance''' in '''C++'''.

| In this tutorial we will learn,

|'''Multiple Inheritance'''.

| To record this tutorial, I am using,

| '''Ubuntu OS '''version 11.10 and

| '''g++ compiler '''v. 4.6.1

|I have already typed the code on the editor.

|Note that our filename is '''multiple.cpp'''

| In this program we will display the '''name, roll no, marks''' and '''average''' of the student.

| This is our headerfile as '''iostream'''

|  Here we are using the '''std namespace'''

|Then we have '''class "student".'''

|In this we have '''roll_no''' as '''integer variable''' and '''name '''as''' character variable'''.

|Then we have another '''class "exam_inherit"'''

| Hence we have two '''base class''' here- ''' student''' and '''exam_inherit.'''

|In this we have 3 '''variables'''-  '''sub1, sub2, sub3''' as '''protected'''.

|Now here we have '''class "grade"''' which is the '''derived class'''.

|This inherits the '''base classes''' – '''class student"' and '''class "exam_inherit"'''.

| In this we have '''avg''' as '''integer variable''' declared as '''private'''.

| Then we have '''function'''

|'''input()'''

 

|'''display()'''

|'''average()'''

 

|'''input_exam()'''

|'''and display_exam()''' as '''public functions'''.

|In this we have '''"total"''' as '''integer variable''' declared as '''public'''.

| Then we use '''input function''' to accept the '''roll_no''' and '''name''' of the student.

| In''' display function''', we display the '''roll_no''' and '''name '''of the student.

| Here we have''' function input_exam.'''

|In this we accept the marks of three subjects as '''sub1, sub2 and sub3.'''

| Then in '''display_exam function''', we calculate the total of three subjects.

And print the total.

| And in '''function average''' we calculate the average.

| This is our '''main function.'''

|In this we create an''' object '''of '''class grade '''which is the''' derived class '''as''' gd.'''

| Then we call all the above '''functions'''

| This is our '''return statement'''.

|Now let us execute the program

| Open the terminal window by pressing '''Ctrl, Alt and T '''keys simultaneously, on your keyboard.

| To compile, type '''g++ space multiple dot cpp space  hyphen o space mult'''. Press '''Enter'''

|Type''' dot slash mult'''. Press '''Enter'''

|I will enter as '''3'''

|I will enter as '''Pratham'''

|''Enter marks of subject1'''

|I will give as '''67'''

|'''subject2''' as '''78''' and

|'''subject3''' as '''84'''

|The output is displayed as  

|'''Roll no is: 3'''

 

|'''Name is: Pratham'''

|'''Average is: 76'''

|Now we will see '''hierarchical inheritance'''.

|In '''hierarchical inheritance,  multiple derived classes''' inherits from one '''base class'''.

| Note that our filename is '''hierarchical dot cpp'''

| This is our header file as '''iostream.'''

| Here we have used the '''std namespace'''

| Then we have '''class  student''' which is the '''base class.'''

| Here we have another '''class 'show'.'''

| In this we have two '''functions: "input"''' and '''"display".'''

|In '''function input''' we accept the '''roll_no''' and '''name''' of the student.

| In '''function display''' we display the '''roll_no''' and '''name''' of the student.

|You can see that there are two '''derived class'''- '''class exam''' and '''class show.'''

|Both the '''classes''' inherits the '''class "student".'''

| In '''class exam''' we have two '''functions''' as '''"input_exam"''' and '''"total marks"''' declared as '''public'''.

| Here we access the '''function "input_exam"'''  

|It accepts the marks of three subjects- '''sub1, sub2 and sub3'''

| Then we have ''' "total_marks" function.'''

|It calculates the total of three subjects and print the total.

| This is our '''main function'''.

|In this we create '''objects''' of three '''classes''' as''' st, sw '''and''' em.'''

| Then we call all the above '''functions.''' using these object.

| And this is our '''return statement'''.

|  Now let us execute the program.

|Let us compile, Type '''g++ space  hierarchical dot cpp space  hyphen o space hier'''

|Press '''Enter'''

 

|Type '''dot slash hier'''

|Press '''Enter'''

|'''Enter Roll no.:'''

 

|I will give as '''4'''

|'''Enter Name:'''

 

|I will give as '''Ashwini'''

|I will give as '''87'''

|'''subject2''' as '''67''' and '''subject3''' as '''97'''

| The output is displayed as

|'''Total is : 251'''

 

|  This brings us to the end of this tutorial.

|Come back to our slides.

| Let us summarize

 

|In this tutorial, we learnt,

|As an assignment  

 

| 07:21

|Create a '''class area''' and '''perimeter'''.

|Find the '''area''' and '''perimeter''' of '''rectangle'''.

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