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‫Okay.

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‫This is going to be our introduction to QuickSort.

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‫So I'm going to bring up an array here like this step.

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‫I'm going to show it like this.

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‫And the way QuickSort works is we're going to have a pivot point and we're going to make that first

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‫item that for the pivot point, and we're just going to compare every item in the array to that number.

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‫So we'll start at the six.

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‫That one's greater.

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‫I'm going to color that grey because it's greater than.

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‫And the one is less than.

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‫So if we find an item that is less than, we're going to exchange it with the first item that is greater

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‫like this.

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‫Then we move to the next one that's greater.

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‫This one's less than we exchange it with that first greater than item.

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‫And we do this again, an exchange that.

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‫And then the five is greater than four.

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‫So we'll color that one in gray.

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‫And we have one step left.

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‫We're going to swap that for with that last item that is less than like this.

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‫And now the four is sorted, so I'll colour it green because that's going to be where it is after we

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‫sort everything and everything that's less than the four is on the left.

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‫Everything that's greater than the four is on the right.

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‫So now what we're going to do is run quicksort again on just this section of the array, and we're going

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‫to do it on the other side as well.

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‫So let's focus on the left side first.

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‫The two is going to be our pivot point now.

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‫We'll compare the one to the two.

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‫It's less and the three is greater than.

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‫And now we're going to exchange the one and the two, and now the two is sorted.

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‫And then we'll run this recursively on these two.

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‫And because there's only one item in each of these, we know that those are in the correct spot.

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‫And I'll mark those as sorted.

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‫On the other side, we're going to have the six be the pivot point.

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‫Seven is greater, five is less.

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‫So we'll exchange these two.

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‫And then we'll exchange the six with the five.

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‫So the six is sorted and now the five and seven are sorted as well.

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‫And that's our overview of the workings of QuickSort.