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‫So now we're going to write our append function and append is going to look like this.

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‫We're going to create a node.

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‫We'll have the last node in the linked list, point to the new node, and then we'll have tail point

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‫to the new node.

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‫And that adds that into our linked list.

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‫That's how we do it if we already have nodes in the linked list.

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‫But if we have an empty linked list, we're going to have head and tail point to the new node.

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‫So what I recommend that you do here is pause the video and see if you can write the code to do this

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‫and then come back and watch the rest of the video where I go over the code.

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‫So we're going to start the code out like this.

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‫Our return type is void because this function does not return anything.

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‫We pass it an integer that we're going to call value, and then we're going to use that value to create

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‫a new node like this.

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‫So now the first situation will code for is when we have an empty length list.

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‫This is where we have head and tail point to the new node.

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‫So the first thing we need to do here is test to see is the linked list, in fact empty.

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‫So I'm going to say if the length is equal to zero and there are other ways you could test to see if

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‫the length list is empty.

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‫You could say if head is equal to null pointer or if tail is equal to null pointer.

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‫Those are all different ways that you could test to see.

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‫Is the linked list empty?

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‫And if it is, we'll want to set head equal to new node that will do this and we'll want to set tail

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‫equal to new node and that does this.

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‫So now let's add this in with the rest of our code like this.

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‫Now let's write the code for when we do have items in the length list, we'll say else and let's build

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‫out this else statement.

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‫We'll say tail next equals new node.

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‫That is tail.

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‫Next equals new node.

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‫And then we'll set tail to be equal to new node that moves this over and adds that node into the length

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‫list.

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‫So now let's add this code in with the rest of our code.

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‫And so far we have created a node.

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‫This is for when we have an empty linked list and this is for when we have items in the length list.

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‫And now the only thing left to do is to increase the length by one.

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‫So that is our entire append method.

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‫And we'll look at this in a moment in VZ code.

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‫And when we do, we're going to create this linked list with one item in it and we'll print this and

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‫then we'll run append and we'll append this second node with the value of two and then we'll print it

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‫out again and we should see one and two.

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‫So now let's flip over and take a look at this.

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‫So there is our append function.

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‫They're not going to scroll up and we're going to look at our main function.

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‫So this line here is going to create a linked list with one item with a value of one, and then with

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‫this line we'll print that out and I'll run this.

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‫And you can see up here, our link list has one node with a value of one.

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‫So now I'm going to come up here and I'm going to add a line.

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‫And this is where we append that second node with a value of two.

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‫And then with this line, we'll print this out again.

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‫So I'll run this.

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‫And now you can see that we have a length list with values of one and two, and that is our function

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‫for append.