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OK, everybody.

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One last while loop video for you.

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This is actually just going to be a little practice problem for you where I will go through the solution,

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but I think that we just need to go over one last little thing with loops in general.

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Specifically, though, while loops for this time, and that is something like this where you need to

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fill in array using a loop.

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So this is a challenge for you.

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This is something that we haven't really done yet, but I think that it is something that you might

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be able to figure out.

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But don't worry, I'll go over the solution.

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So here is our problem statement.

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It says Ask the user to fill an array with integers one position at a time once the array is full.

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Go through that array and print out all the elements on the same line where the numbers are separated

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by spaces.

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So.

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Here is the description.

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I am going to let you go ahead and pause the video to see if you can figure this out.

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And then I will go ahead and walk through it.

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OK, so I'm going to go ahead.

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I already have the code kind of written out here, but I'm going to go ahead and explain it.

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So the first thing that we want to do is make an array.

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I have hardcoded it here.

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There's something interesting that I want to point out is that you can sometimes do something like this.

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Let's say you were to get something from a user like a number and size and then you see in size.

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It is possible to.

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Put size here only on specific using a specific C++ compiler.

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It's actually from.

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The I think it was from the not C++, but C ninety nine or something like that allowed something like

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this, but certain compilers, I think you might get an error if you do something like this.

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So I'm going to put it like for this lecture, I'm going to put it just like hardcoded.

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But you could go ahead and try and put safe here.

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Do something like this.

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If you want to get the size of the array from the user, you could do something like this.

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But I don't think that this is a good programming practice because it might not work on certain C++

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compilers.

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You might get an error, as far as I know.

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So I would say put this.

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Five here, and we'll just kind of leave it like that in the next video, I might just go ahead and

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use that size thing because it does work with my compiler, but it's not good programming practice.

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To do that, we will talk about what we can do to make dynamic sized arrays rather than fixed size arrays

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later on.

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So then I have this interposition position as well because I need to fill an array with integers one

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position at a time.

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So what I'm going to do is make this little counter variable so I can know which position to put what

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integer in the array.

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Remember, an array is an indexed container, so we're able to place things at certain indices.

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If you forget about that, go ahead and maybe rewatch the lectures where we have talked about race and

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used to the floor.

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So I also have this count right here.

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This is something that I am defining for the second part, because I could use these same variable,

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but I chose to use a different one to index it when I printed out.

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So let's continue on to see what else I put here.

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So let's take a look here at the loop.

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So what we're going to do is loop as long as the position.

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Is less than five, and why is that less than five?

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See if you can answer that for yourself, the reason why is because the last item in nuns is actually

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position four, because it starts at zero.

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Remember really important things about race and pretty much most containers in C++ starting this zero.

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So.

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Then we asked the user inside the loop to enter a number for the position, and I print out the variable

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here position.

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What we do at that point is we read in directly into the array, so that's kind of cool, right?

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We are able to read directly into the array right here.

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So how we're doing that as we're doing a scene, we use the name of the array and just like we've read

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into an array position before now instead of hard coding it like we're not putting a number here in

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this highlighted section, we're putting the current position that we're on and when I say current.

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That has to do with this next line, because what I'm doing is I'm actually increasing the position,

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each iteration of the loop.

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So each time we go through this while loop, I'm doing a plus plus position and I'm going to keep doing

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that as long as position is less than five positions started out as zero, right?

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I say, let's go as long as physicians are less than five and here is where we increase it from zero

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up until it's five.

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When position is five.

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None of this code will run because the condition explicitly says that it will only execute this code

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and here, as long as possession is less than five, you see in the less than sign here.

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But the important thing is that the position is being incremented and it is also being used to fill

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each next slot inside of our array.

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Right.

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So then we come to this next part, the next part said that we need to then go through the array and

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print out all the elements on the same line where the numbers are separated by spaces.

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So that is exactly what we do here.

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We do a similar thing, I put another variable kind of just for visual purposes.

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I could have reused position.

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The way that I could have done that was to do something like position.

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Oops.

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Position equals zero.

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So I reset position.

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From being five to zero, because you know that what happens when this loop is done, position will

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be equal to five.

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And so it will come down here and do the code.

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That's after this wildly.

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And so at that point in time, position would be five.

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So what we have to do is reset it to zero.

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That's something we could do, is what I'm saying, but we don't need to because what I did was I just

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made another variable called count, which is essentially the same thing as position is just going to

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be used in this loop.

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So I say, well, count less than five, then what I do is I see out.

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The NUM's position count.

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And then a space.

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And so what happen, for example, is the first time it runs count will be zero.

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So it'll print out numbers at position zero.

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And then it'll put a sprint out of space.

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It will then increment the count variable, so now count will go from zero to one.

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It'll come back up here.

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It'll be like is one less than five.

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Yes, it is.

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So then it will go here and it'll say, Let's print out NUM's position one.

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And then a space go down here, count gets increased to two.

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We go up here to is less than five.

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We keep going and we keep going until count is five.

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And then we're done and we return to zero and our program is finished.

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OK, so that's really all there is to it.

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If you weren't able to figure it out, don't worry.

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Like I say in each lecture, it's not that big of a deal.

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We're just trying to practice so you can feel more comfortable with these concepts.

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So we will keep having more and more problems.

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This is most likely going to be the last videos about while loops specifically, but we're going to

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continue on with loops and later on in the course we're going to be using while loops more so you'll

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get more practice with them.

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All right.

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So with that, I will see you in the next lecture, except in the next lecture, I think what I'm going

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to do is I.

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We're going to introduce another type of loop, and I may potentially use this kind of thing where I

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read into a variable.

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But I want to point out that.

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Doing something like this for an array is generally not good practice.

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They raise they somewhat seem they might somewhat limit us now as far as what we know about it, but

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we are going to talk about a way to find a way to put a variable in here rather than just a number in

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the near future.

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All right.

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So just take note of that, that it might work.

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You might be able to do that, and I might just use it in the next lecture.

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But it's bad practice to do that when you're making serious programs and stuff like that.

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So I want to point that out.

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OK, with that, I will see you in the next lecture.