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Hello everyone.



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So in the last week we discussed how construct a sound destruct those are calling gifts of inheritance.



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So in this we do I want to discuss different types of inheritance.



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Okay so the first one is Single inheritance.



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Now what is the meaning of Single inheritance.



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So it means only one parent and one child.



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Okay so class be inherited glasses.



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So one parent and one child vehicle and God.



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Okay so only one parent and one child.



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So what is this index syntax is quite familiar.



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Class God then access modify it and then the name of the class which is we call.



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Okay so this is the syntax for Single inheritance.



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Now the second is we have multi level



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multi level inheritance



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okay.



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So what is the meaning of multi-level inheritance.



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So in multilevel inheritance we have multiple levels.



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Okay.



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So for example Class B inherited from Glass a glossy inherits from Class B and so on.



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Okay.



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So we took an example in the last session so we could class this guide class inherits from the working



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class and then we have 130 class which inherits from the Carter class.



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Okay so how do the properties will be accessible so well it depends upon the access modifiers you use.



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Okay.



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Now the third one is now the third one is hierarchal inheritance.



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Okay so radical.



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Inheritance so what is the meaning of identical inheritance.



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So in this case we have one parent and multiple child.



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Okay so only one parent will be there and there will be multiple child B C and D.



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Okay now let us take an example.



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So we have a weaker class car class inherits from the class bicycle class inherited from the working



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class.



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And similarly that class will inherit from the.



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We could class.



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Okay so multiple class in added the base class.



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So what is this index.



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So this index is quite familiar for example if we want to use track class so class truck and then public



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vehicle public is the access modifier.



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Okay so let's say in gold although the code is not necessary but let's see



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so I want to create a class class drug.



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Now this class drug inheritance tax is modified is public and it inherits from the working class.



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Okay



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and that's all okay.



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So we can see here is Class Card which also notes from the working class.



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And similarly there is a class drug which also includes some division of class.



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Okay



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so this was hierarchal inheritance.



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Okay now let's see the next one.



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So the next one is the fourth one is now this is a multi-level might be level inheritance



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so what happened in multi-level inheritances so one class will inherit from multiple base classes.



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Okay.



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One class will inherit from multiple base class letters a b c and d a Class D so one class will inherit



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from the multiple base classes.



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Okay so suppose we have Teacher Teacher class and student class



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and the third one is the teaching assistant.



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Okay so a teaching assistant will have some properties of teacher and teaching assistant is also a student.



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Okay so when a class will inherit from the multiple B's classes.



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Okay so let's say in good



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so I have this class multiple inheritance starts CPB sorry I have this file multiple in our TPP Let's



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create two classes.



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So class teacher so this class teacher has some public properties let's say the properties are name



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and age.



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Okay so String name and legacy and Deej also let's say there is a print function where the print inside



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the brain function let's print something.



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Okay so we'll see old



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digit Okay now let us also create a class.



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Student So we have a class.



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Student now this student.



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Class let's say it also has a function print.



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So void print.



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And now that this print a student inside the print function.



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So student Okay now we have a class teaching assistant so this class teaching assistant as you can see



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here this class teaching assistant it inherited from both the classes or damage it inherited from the



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teacher as well as from the student class.



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Okay.



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And let's see the excess specified is public so class teaching assistant this index is very similar.



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First we have to rate the excess modifier.



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Let's say the excess modifier for the teacher class is public then coma again excess specified for the



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student class.



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And then the name of the student class.



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Okay so this is this index for multiple inheritance.



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Okay so this class teaching assistant it inherits from both teacher class and grade class.



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And for both the access specified is public.



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Okay.



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Now what will happen if I want to create an object of their teaching assistant so teaching assistant.



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Let's see the object is a the name of the object is it.



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So what is happening here is okay.



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So we have teacher and student.



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So I have a class teacher and I have a class student and then I have a class teaching assistant it inherits



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from the teacher and the student.



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So



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this is teaching assistant class and teaching assistant class in edits from teacher as well as it inherits



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from the student.



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Okay now what will happen when I write this statement when I'm creating the object of the teaching assistant



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class then whose construct that will be called first.



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Okay so it generates from teacher and it then added strums truant from what the classes.



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So whose construct will be called first teacher or student.



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Okay so the answer is teacher y teacher because I write teacher first.



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Okay so because I write the name of the teacher class first.



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So that's why.



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First of all teacher constructor will be called then student constructively record.



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And finally the teaching assistant constructor will be called when we are creating the object of the



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teaching assistant.



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Class okay.



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Now let us try to not let us use the print function.



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Okay so now let's call the print function.



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So what will happen.



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Okay.



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So if I run this file there will be an error.



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Now let us try to understand why the error will come



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so what is happening it is.



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So first of all this print function is accessible for teaching assistant.



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Why.



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Because as you can see here is print function is public.



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And similarly the print function is public here and we are using the access specified public.



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So teaching assistant has access to the print function.



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Okay now what is happening here is we have a teaching assistant class and in their teaching assistant



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class we have a teacher and we have a student and teacher class has a brain function.



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Similarly student class also has a print function.



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So when I am calling the print function I am telling you there will be an error and that I will be there



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because there is ambiguity whose print function to call compiler will get confused.



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Okay so compiler will get confused among whose print function to call Deja brain function or Australian



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print function.



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Okay so that's why I edit will be there.



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If the print function is present in one class then there will be no idea.



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Okay so suppose if the print function was not present here then obviously there will be no error obviously.



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Then this print function would have been called.



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Okay but what is happening it is both the teacher and the student classes.



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They both have the print function exactly the same name.



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That's why the compiler will get confused because there is ambiguity whose print function to call.



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Okay.



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So if we will run this file we will get an error and that it will be saying like like there is some



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ambiguity in the brain function.



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Okay so let's try to this file.



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Okay.



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So we are getting an error at this line and that will be something like print function present in multiple



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base classes.



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Okay so we have two basic classes.



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Student and teacher.



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So we have two base classes and the brain function is present in multiple base classes something like



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this.



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Okay.



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Now how can we resolve this issue so to resolve this that we have to specify the class name.



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Okay suppose I want to call the print function present in this to rent class.



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So what I will write a dot student name of the class whose print function we have to call and the scope



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resolution operator.



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Okay.



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Now this time I will run this file.



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There will be no error and output will be student.



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Okay.



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This this print function will be called.



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Okay so this print function will be called.



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Okay let's straight on this file



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so a student is getting printed.



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Okay.



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Now what if this teaching assistant class also has the function brain function.



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Okay now what I'm telling you is now where did the teaching assistant class also has the function print



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and inside the brain function.



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I am writing teaching assistant Okay.



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Now what will happen and let's say if I run this file then the output will be student only because it



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is very clear here that we are not we want to call the brain function as truly in class.



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OK so let's send this file produced protested and no doubt.



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Now what if I remove the student.



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Now what will happen if I do a dot print.



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Will we get any added Now they're desperate to find out.



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So this is our teaching assistant class so in that teaching assistant class we have teacher and it inherited



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from a student.



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So teacher has a print function.



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Student also has a print function and teaching assistant has also has a print function.



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So what happens internally is when we write it out.



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So what it will do first of all we will search in the teaching assistant class and the teaching assistant



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class has a function called Print.



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Since the teaching of history in class has a function called print.



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So we will not go to its parent classes.



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Okay we will not go to its parent classes and this print function will be called and our output will



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be D.



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Okay.



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Now what happens is in the earlier case their teaching assistant class doesn't have a print function.



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So if the teaching assistant class doesn't have a brain function then we will go to it parent classes



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and both the parent classes as print function.



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That's why there will be an added ambiguity in it.



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Okay.



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So let's try to run this file and our output will be teaching assistant.



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Okay so our output is teaching assistant now just like the function if we have multiple data members



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with the same name then we will also get the error and that it will be like did the member present in



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multiple base classes for example this teacher the teacher class has a string name property let's say



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three and also has the name property.



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Okay.



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Now we can see here same name.



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Okay.



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Now if I want to let's say I want to access the name date remember.



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So a node name is let's say a b c d.



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Now if I had this file I will again get data and that it will be ambiguity added.



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Okay.



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So we are getting an added.



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Now how to resolve this error.



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Again we have to specify the last name.



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I want to exist the name property of the teacher class.



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So a dot teacher school resolution operator.



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Okay.



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Now let us on this file.



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So now all code is working fine.



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Okay.



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Now let us revise everything.



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So we have discussed four types of inheritance single multilevel and hierarchical all the three were



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very simple.



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The last one which was multiple this was a little bit tough.



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Now what happens in multiple is.



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Suppose you have three classes a b and c and let's say you have a class D and class D and added from



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all the classes glossy class B and classy.



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So this is the example of a multiple.



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It is the example of multiple inheritance.



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What is the problem with multiple inheritances.



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So if you ever need a member or function with the same name in multiple base classes then there will



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be an added.



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And how does all this error.



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So we have to specify the class name so d dot first of all that last name then the school resolution



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operator and then the property name.



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Okay so what is the problem with multiple inheritance if more than one if more than one base class.



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But as a written member with the same name or the function name then they will be added ambiguity it.



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Okay.



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And resolve this error.



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We have to specify the class name first and then the property name.



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Okay.



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And the second was if the properties also present.



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Suppose the properties also present in class D then that property will be accessed.



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Okay.



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Then there is no confusion.



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We can simply access this property okay.



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Now there is also a fifth type of inheritance which is the hybrid inheritance which we will discuss



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in the next video.



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Okay.



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Thank you.