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Hello.

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In this lecture you will learn about the cplusplus writing techniques and language features.

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So Cplusplus is a very flexible language when it comes to formatting and writing code.

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So it's also a strong type language.

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So meaning that there are rules, but clearing the types of variables which you can use to your advantage

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by making the compiler help you write better code.

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In this section we will cover how to format Cplusplus code and the rules on declaring and scoping variables.

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In this lecture we are going to start with the white spaces.

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How you can use white spaces in cplusplus.

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So here, other than string literals in white spaces, you have free usage of white spaces.

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So you can as long as as many as you can use as many as tabs, spaces, uh, spaces, spaces and new

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lines.

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New lines.

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As you can see here.

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You won't get you won't you will not get any error because of it.

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Here, as you can see, you can use as long as many as new lines, tabs and spaces you want here.

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As you can see.

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Let's compile it.

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As you can see, C plus plus compiler doesn't care about them.

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So.

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So about C plus plus statements are eliminated by semicolons here, as you can see here.

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So let's create an example code.

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So to explain it better.

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So for example, let's create an integer variable, assign it four and integer equals integer derived

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by two.

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So we will get two from it.

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And let's print F print f this.

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As you can see here, we get we got an error because in print F so we have to use the print we have

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to use in include library, you will learn about how to include library and what library is in later

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lectures.

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But it's not a hard thing to learn, but you will learn in next lectures include here.

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Um.

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STD dot h here.

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As you can see, we got rid of this error here.

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Return.

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Uh, let's return zero from it.

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Integer function.

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As you can see here, this function returns zero.

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You will learn.

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And then here, as you can see, we got the format.

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Um, then.

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And let's print something on it.

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So as you can see, if you if you delete this, include statement, this we will get an error here,

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as you can see here.

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And.

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Yeah.

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Let's include our statement here and delete this common line.

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Clear And yeah.

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So let's print these values on it.

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Actually, let's, let's use the C out we will use.

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We will we will use the printf later in this course.

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So as you can see, we got an error from it.

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Let me write this code.

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The result result is we will pass E as you can see, we will pass E and then end line here.

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End line.

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So as you can see, we've got an error.

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So if you include the stream.

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Yeah, you will get rid of that error.

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That's because the STD library needs input output stream here, so.

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And and as you can see, if we delete the printer function so we are not using print function anymore.

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We don't need this library.

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And as you can see here, see line ID, this blue, just the gray, gray color, this text for it.

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And then here.

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As you can see here, we have a new line here.

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Um.

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Every between our line and let's run and compile our program.

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And we got a result here.

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The result is two.

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So let's try one example here.

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Just delete these new lines.

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Yes.

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Just let these new lines and let's try if this works here or this.

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Here.

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We need these two semicolons and we do this too.

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So you can put spaces on new lines between variable names or functions or whatever you want here and

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you can use here.

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As you can see, we got the same result.

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So there are some cases white Spaces is needed.

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For example, when declaring a variable, you must have a white space between the type and the variable

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name.

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So but the convention is to be judicious as possible to make the code readable.

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And while it's perfectly correct language wise to put all the statements in one line like a JavaScript,

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but it makes the code almost completely unreadable.

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So of course it's less readable than the previous, uh, previous codes here, as you can see here,

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let me here, this is more readable, right?

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So actually, let's, um.

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Let's correct let's note this because I'm uploading this files to every lectures, and you can download

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and use these codes by letter.

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So for example, correct by language wise, but readable and readable and readable.

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And let's collect let's write another code here.

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For example, let's so as you can, as you know, we can create a two variables at the same name.

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So I'm going to change these names here.

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Uh, so.

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Of course you can print the as long as you want, but you just can't create the same name, same name,

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variable, same named variable.

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So as you can see here, this is here.

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Here.

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This is correct.

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Correct.

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By language wise.

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All right, let's just create a program will compile.

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Without problem but unreadable.

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So I will explain why we need this.

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Readable and unreadable codes here now.

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So.

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Being in mind that if the code write code you write is viable, it may use.

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It may in use for decades, which means you may have to come back to code years after you've written

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it.

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And it means that other people will support your code too.

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So making your code readable is not only a courtesy to other developers, but unreadable code is always

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a likely target for replacement here, as you can see here.

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Of course, it's more readable than this, so.

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In this lecture.

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In next lecture, you will learn about the formatting, the code in C plus plus.

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So see you in the next lecture.