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So let's start off by looking at vectors and look at some of the methods that are associated with the

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vector.

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So we'll create a mutable vector called nums, and we're going to just put in values of AI 32 and we

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want our vector to be empty to start.

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So we looked, we saw this earlier in the course.

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We can use a push method to add values into the vector.

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So let's do that and let's just add in a few values here.

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So one way that we can remove values off the top is by using a method called pop, and this actually

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returns a value.

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So we can actually say let pop equals number pop, and then we can print out this value.

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It's not implement.

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So there we go.

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So now we can run this.

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We can see that we returned some three.

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So this returns an option of type T.

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So remember this can either return none or some T, and in this case it popped some three.

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So think of this as a stack of plates.

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So we're going to.

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Push plates onto the top.

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And then when we pop, we want to take off the last plate.

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So in this case, three that we pushed on to the stack.

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So we can also, just as a review, reference some of the numbers so we can say let two equals num one.

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And since we're doing I 32, this would just be a simple copy.

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But if we were doing another value that doesn't implement copy, we could create a reference to it in

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this case.

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So creates a reference if copy is not available.

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And then just to show you that we were able to successfully copy it, we'll say too and we'll run it.

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And we got two.

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So great.

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So.

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There's a couple of other ways that we're able to return values.

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One of them being let one equals numb dot first.

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And as you can imagine, this is going to return to us the first value and our vector.

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But again, this is going to return an option T, so it's going to be none if the vector is empty

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or some t.

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If.

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Now if the vector is not empty because we're going to take out the first index.

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So we want to return the we want to get the first value.

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So let's make sure that one successfully did just that for so one.

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And we returned some one, which is great.

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That's the expected value that we were anticipating.

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So we can also do that last and just like first, instead of it being first, this is going to return

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the last value in the vector.

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But we also have to first mute and last mute.

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And as the name suggests, it's going to be the same as first and last, but it's going to borrow mutable

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references.

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Will borrow mutable references.

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So if we want to check out the length of our vector, we can do nums, dot length, line short for length.

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And then if we want to do a quick check to just see if our vector is empty, we can do nums dot is empty

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and this is going to return a boolean, whereas this will actually return a value of the length.

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Another way that we can add values inside a vector is using insert, but insert is going to allow us

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to.

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Insert at the index of our choice so we can say insert at.

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Index zero.

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So the first index and we want to insert ten, but we can also say nums dot insert at the three and

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we'll put in 12 and then we can do nums dot insert two.

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And we can put in the value of 25.

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So like insert we can remove with nums dot remove and then we can just specify the index that we want

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to remove.

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So in this case, let's remove index three.

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And then if we want to sort everything out, we can do nums dot sort.

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And now let's look to see how it would appear sorted just to make sure everything looks good.

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And now we're going to do nums.

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So we run it.

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We see we have 110, 12 and 25.

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Looks sordid to me.

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And we can also run a method such as reverse, which is going to do what we expect it to do, which

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is just going to reverse it.

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So in this case, since we've already sorted it, I expect it to be 25, 12, ten and one, which is

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great.

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That's exactly what we got.

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So something else that we can do is we can actually have our vector shuffled.

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So in order for us to do this, we need to go into our cargo file and we need to specify that we want

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to bring in the RAND package.

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So we're going to say Rand and then we're going to do version 0.8.4, which is the latest version of

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Rand at the time of this recording.

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We'll save that file.

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And then we'll come to the top outside of Maine and we're going to say, use rand.

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Seek and slice random.

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And then we're going to say use rand.

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Thread.

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Rand.

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And now down here, we can say nums, dot shuffle.

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And it's going to say want a mutable reference to the value generated to us by thread random number

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generator.

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That is what RNG stands for.

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And now if we print this out, it's going to shuffle our vector for us and we'll run this a couple of

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times to make sure that it is being shuffled.

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And we got ten, 25, one and 12.

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And then we got 12 one, 25 and ten, and then we got ten, 12, 25 and one.

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So it does appear to be shuffling as we intended.

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So these are just some examples, examples of what vectors have to offer in rust.

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There are many more methods we can use, so I do encourage you to play around with all the methods associated

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with vectors.

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That way you become familiar with all the.

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Methods we have at our disposal.