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‫So now we're going to create our delete first function.

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‫I'll bring up a doubly linked list and with delete first it's just going to look like this.

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‫And we have an edge case for when we have one node and another edge case for when we have an empty linked

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‫list.

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‫So we'll start the code out like this, and the first thing we'll do is write the code for when the

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‫linked list is empty.

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‫Will say if the length is equal to zero, we'll just run return.

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‫So now let's write the code for when we have one item in the length list.

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‫We'll start out by creating that variable temp and we'll create it like this temp equals head, and

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‫then we'll say if the length is equal to one, we'll set head and tail to be equal to null pointer.

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‫Like this.

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

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‫So this is for when the length list is empty, and this is for when we have one item and for two or

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‫more items we'll say else.

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‫And now let's build out this else statement.

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‫We'll move head over by saying head equals head next.

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‫And we'll do that with this line of code.

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‫Head equals head next.

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‫And that'll move that over.

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‫Then we'll say head previous equals null pointer and that'll do that.

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‫And we'll do that with this line of code head previous equals null pointer.

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‫So let's add this in with the rest of our code and we have a couple more steps to do and we'll say delete

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‫temp and that will remove that node from memory and then we'll decrement the length by one.

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‫So let's add this in with the rest of our code and that is the entire delete first member function.

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‫We'll look at this code in a moment and VS code.

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‫And when we do, we'll create this doubly linked list and then we'll run delete first three different

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‫times to make sure it works when we have two or more items and one item and then we'll run it a third

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‫time to make sure it works when the linked list is empty.

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

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‫So there is our delete first member function.

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‫They're added to our doubly linked list class, and then I'll scroll up and in our main function that

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‫creates that doubly linked list with values of two and one.

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‫And with this we'll print out that linked list and I'll scroll up again.

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‫And with this code we'll run delete first three different times.

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‫First, when we have two items and then with one item and then we'll run it a third time to make sure

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‫it works when we don't have any items.

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‫So I'll run this.

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‫And up here we have our double length list with two items in it.

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‫And then we ran delete first and removed one.

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‫And then here we ran it again.

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‫And the doubly linked list is empty.

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‫So we run it one more time to make sure it works on an empty, doubly linked list.

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‫And it looks like we have a working function for delete first.