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Hello, everyone.

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In this video, we'll set up Visual Studio code to debug C++ programs.

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We've already set up IntelliSense and we've set up a build task.

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So now we're going to set up the debug.

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Where do we start?

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It's really quite simple.

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Select one of your C++ files, it doesn't matter which one, and then come up here to run and add configuration.

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Now you can be asked for your environment, select C++, GDB, LD, DB, and then the C++ compiler again,

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which in our case is G plus plus.

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Now you're going to have some stuff happen and things are going to be changing colors and so forth.

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Don't worry about any of that.

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What we're going to do now is modify this file that was just created called Launch JSON.

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We're going to make one minor change to it.

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You close this window up so we can see it.

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What we're going to do is we're going to change the entry for CW.

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DX It's on line 14 on my system here, and we're going to change this from workspace folder to file

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your name.

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So I'm just going to copy that.

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And paste it in here.

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And that's all we're going to do.

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Now, I'm going to save this and I'm going to close it since we don't need it any longer.

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All right, let's debug our first program.

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Let's modify Project Two's main CPP file just a little.

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So we have a little bit information to see in the debugger.

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So what I'm going to do here, I'm going to add an integer and let's just call this my favorite number

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and I'm going to initialize it to, let's say, 100 just so we have something to look at.

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So it's still going to display hello from Project two, but now we want to prompt the user to enter

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their favorite number.

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So we'll put another display statement in here.

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We'll just say Enter your favorite number and then we'll read in what type, and we're going to read

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that into favorite number.

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And then finally we're going to display your favorite number is and we'll display what they typed in

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right back at them.

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So we'll say your favorite number is and we'll display what they entered fave number, followed by a

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new line.

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All right, so that's it.

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So we made a small change, but an important change because we want to be able to see that favorite

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number change in the debugger.

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All right.

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So how do we debug now select the program you want to debug?

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Again, very important that we select that CP file that we want to debug.

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In this case, this is the one we want to debug.

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What we can do now is we can click that bug icon right there where it says run and debug and nothing

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will happen right away.

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But we need to do is we need to set a breakpoint in our code.

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This is where the debugger is going to stop when when it starts to debug our code.

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So I want it to stop right there, right on line five, so you can just move along here and just select

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the breakpoint, just click and it turns red and you can select as many breakpoints as you want.

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Notice now that the breakpoints show up here, there is a glitch in Visual Studio code where sometimes

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when you have multiple breakpoints across different projects, they all show here.

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And what I recommend you do is when just when you're about to start debugging, click on that X right

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there that erases all the breakpoints from everywhere.

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Now, you don't see any down here, and then you could just come up to your project and put the breakpoint

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exactly where you want it.

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So now that we've done that, we can click on this little green run icon right up here.

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And when I do that, the debugger will engage.

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You can see that there's a build happening and now this bottom bar turns orange.

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And now there's a couple of things that have just happened.

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Notice that this line five is highlighted and the play head is right there, right on line five.

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That tells you that the debugger stopped at line five just like you asked it to.

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That's where you put the breakpoint.

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So line five has not been executed.

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Line four has notice that line four is our declaration of favorite number.

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And if you look over here in your local variables, there you see its value.

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That's pretty cool.

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So you can see favorite number is 100 and you can also hover over favorite number.

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You'll see the 100 pop up.

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You can do that anywhere it occurs.

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Now, what we want to do is we want to execute one line at a time and we could do that with this button

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right here.

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You can see we've got a series of buttons here that allow us to interact with the debugger.

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This steps over the code, it steps into code and I discuss these in more detail throughout the course

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here.

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We can just stop the debugger and here we can just continue.

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So what I want to do is I want to execute one line at a time.

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So I'm going to select step over and you can see the play head now moves to line six and the line five

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executed and displayed something on the screen just like we expected.

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All right.

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And now it's going to ask me, what's your favorite number?

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So I'm just going to type in something other than 100 so you can see a change.

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This is type in 45 and I'll press enter and notice my local variable right here, 45.

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That's pretty neat.

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This allows me to step through my code and see what's happening.

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Maybe I made a mistake somewhere.

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It's much easier to see it this way and then we can just continue running the program and we're done.

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So you see.

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Hello from project to enter your favorite number?

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I entered 45 and then it displayed.

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Your favorite number is 45, just as we expected.

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When you're done debugging, you can click over here, go back to explore and just debug or code whatever

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project you like.

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All right.

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So that shows you how to set up debugging.

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So at this point, we've got building, we've got running and we've got debugging all set up.

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In the next video, I'm going to show you how to use Visual Studio code with the source code that I

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provide for the course.