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In this lecture.

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Firstly, we will start with fully featured cplusplus classes using it and we will get and write some

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practical examples about it so the pod classes can contain only data members and sometimes as you want

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from a class.

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So however, designing a program using only pods can create a lot of complexity.

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So you can fight such complexity with encapsulation, a design pattern that binds data with the functions

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that manipulate it.

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So placing related functions and data together helps to modify the code in at least two ways.

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The first, you can put related code in one place which helps you to reason about your program.

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You can understand how a code segment works because it describes in one place both program state and

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how your code modifies the state.

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The second you can hide some of the classes, code and data from the rest of your program using a practice

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called Information Hiding.

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So in Cplusplus you achieve encapsulation by adding methods and access controls to class definitions.

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So we have a methods in classes here.

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So methods are member functions.

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They create an explicit connection among a class.

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It's a data members and some code.

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So defining a method is as simple as adding function to just a class.

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So methods have to all of the class members.

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So consider let's for example, create another method here or first let's create struct date and my

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date and time.

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Here, then add a void method add year here.

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And here.

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Year and increment year.

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By one.

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Here.

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And let's define the year variable here or define here.

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Integer here.

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Here.

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So.

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As you can see, the ad year method declaration looks like another function that takes no parameters

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and returns no value.

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Within the method, you increment the member year year by one.

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So let's create another example here, which we created our struct and methods and we're going to write

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some code in main function.

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So for example, my time or.

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My date here.

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Firstly, my date and time.

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My date here.

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AMD or for example, then.

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Indeed that year.

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Equals, for example, 2022.

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And then that add year.

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Here, we will call this function.

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As you can see, this takes no parameters.

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So if you put anything here, integer, for example, we will get an error and let's end that.

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Let's print the firstly, print our MDR here.

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Here.

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Here.

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The and new line we will pass.

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Yea.

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Yea.

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Yea.

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And then after calling this function we will use printf.

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Yea again.

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Yea.

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Yea.

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And the year m-dot.

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Yea.

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So let's run our program.

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As you can see, we got this output here.

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So you declare the.

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My date and time aimed instance here.

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So and then set the year of set the year variable here to 2022.

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Next you call the add your method on the clock here.

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Actually, firstly, you print it.

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As you can see this is the output and then you call the method here add year, which takes no parameters

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and returns nothing.

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So this is a void class and then print the value of clock m'dear.

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So you complete the program by incrementing and printing once more.