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Now that we have a good understanding of what a queue is, we are going to implement our own queue.

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For this implementation, we are going to use the linked list collection.

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So we need to bring that into scope using standard collections linked list.

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So now we have our linked list brought into scope.

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We can create our queue struct, which we're going to do over type with type T, and we are going to

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have our element of a linked list also of type T.

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So now that we have our struct created, we can implement methods on our queue with the first one being

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our new method, which is going to return a queue of type T, and inside of here we have our queue struct

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which is going to have our element which is going to be a new linked list.

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So now that we have our queue created with our link list that is going to store our elements, we can

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now start putting elements into our queue.

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But remember a queue is FIFO first in, first out, So we need to keep that in mind when we are pushing

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and popping values.

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The two went out of the queue.

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So our first function is going to be called on queue.

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And what we're going to have is a mutable self with a parameter of a value of type T, and this is how

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we're going to push values into the queue.

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So with it being first in, first out, when we push a value in, we need to push it technically to

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the back.

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So since we are using the linked list from the collections, we have a function or a method and the

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link list called push back and push back.

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It's going to put it at the back of the line, if you will.

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For Deku.

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This is going to be our pop method again.

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We're going to have to have a mutable self and this time we are going to return our option.

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With our value inside of it.

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So since we need to get the oldest element in the queue, we need to use the pop front.

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Acid that is associated with the leaked list and this will get the value at the.

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Front of the queue.

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So the oldest value

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now we want to implement our peak method and peak.

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Since it's just going to return a reference, we can return an option that is returning a reference

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to the value and we will say self dot element, dot, front and front is a method with the link list

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that allows us to get a.

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Reference return to the value at the front of the link list.

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So now we're going to implement our length method

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and this is going to return a user size.

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And then here we just want to get the length of our linked list so we can return our link method.

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And then lastly, we want to implement is empty

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and this is going to return a boolean

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and if our elements.

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His empty arc is our link list empty.

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If it is, then we will return true.

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Otherwise we return false.

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So.

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It's a very simple way of implementing a queue using a linked list from the collections library.

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But now I want you to take some time to create the test cases for this, and this will be our assignment

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for this section.

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And then in our next lecture, we will go over my test cases to ensure that our queue is functioning

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properly.