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Let's add a simple main function.

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We add parameters here and we're going to preheat provide with.

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Basic input output using the include input output stream here and we're going to use the string in this

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practice.

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Practical example here.

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So include string here.

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So here about the main function.

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Add a definition for the structure that represents a task in the list here.

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Ask and ask one to your P next and string description.

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Here.

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So this has two members.

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The guts of the object is the description item here.

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So in our example.

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Executing a task will involve the print printing, the description item to the console.

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So in an actual project you will most likely have many items associated with the tasks and you may even

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have member functions to execute the task.

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But we have not covered the member functions in this course, which is the topic of another next lecture

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here.

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So the plumbing of the linked list is the other member P next here.

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So not the task structure has not been completed defined at the point that the P next member is declared.

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So this is not a problem because the P next here is a pointer.

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So you cannot have a member of any undefined or a defined type because the compiler will not know how

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much memory to allocate for it.

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So you can have a pointer member to a partial defined type because a pointer member is the same size

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irrespective of what it points to.

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So if you know the first link in the list, then we can access the whole list.

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And in our example, this will be a global variable.

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So when constructing the list here.

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The construction functions need to know the end of the list so they can attach a new link to the list.

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Again, for convenience, we will make this global variable here and the following pointers after the

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definition here.

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Here.

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The following pointers after a definition of the task pointer like that, hear it and looped.

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BTR and task here.

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The current.

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No, Peter.

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So as it stands here, if we execute this.

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This code does nothing, but it's a good opportunity to compile the file to test that there are no errors

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in our code share.

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So let's add the task object to the list here.

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So in this project, the next thing to do is to provide the code is to add add a new task to the task

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list.

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So this needs to create a new task object and initialize it appropriately and then add it to the list

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by entering the last link in the list to point to a new link.

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So above the main function here, add this queue task here void to.

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Ask and consent.

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Screen name.

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Here.

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So the parameter here is constant, this constant.

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The parameter is constant because we will not change the parameter and we do not want to overheat of

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a copy being made.

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So by the way, I want to mention that this is not not just the variable, this is constant reference.

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As you know, we make this ampersand before the variables to make them references.

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So the first thing in this function, this function must do is create a new link.

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So we're going to add the task pointer.

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Ask P task.

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Task.

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The task.

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Here.

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New task.

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And he task.

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This operator.

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You know it from the previous lectures.

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Description and name.

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P task for next year and we're going to assign it to New Peter.

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So the first line creates a new link on the free store and following lines to initialize it.

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So this is not necessarily the best way of initializing such an object.

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And the beta mechanism is a constructor, so the constructors will be covered in next lectures here.

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So notice that the P next near P next item is initialized to NULL.

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Peter.

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So this indicates that the link will be at the end of the list.

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So the final part of this function adds the link to the list.

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So this is, it makes the link the last in the list.

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So however, if the list is empty, it means that this link is also the first link in the list.

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So the code must perform both actions here and we're going to add.

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Here.

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If.

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Here.

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If New Peter.

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He had.

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Then he had.

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He task.

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The task.

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Oops.

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Okay.

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He had is p task.

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And then p current.

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The test.

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Else.

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Here.

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The key current.

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E next.

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And this equals to P task.

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The current.

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To task here.

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So the first line of the code checks to see if the list is empty.

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So if the if the P hit is null this, it means that there are no other links and so the current link

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is the first link.

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So and so both P heat and the P current are initialized to the new link pointer.

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So if there are existing links in the string, the links has to be added to the last link.

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So in the first class here, the first line, the first line makes the last link point to the new link

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and the second line initialize the P current with the new link pointer, making the new link to the

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last link for any new insertions to the list.

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So the items are added to the list by calling this in the main function.

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So in this example we will queue the tasks to a paper room.

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So this involves removing the all well paper filling any holes in the vowel, sizing the vowel, and

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then hanging the passage papers to the mouth.

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So you have to do these tasks in this order so you cannot change the order.

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So these tasks are ideal for a link list.

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So in the main function we're going to use the queue task here.

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As you know, we made this void function in this here we're going to use the queue task and remove all

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wallpaper, for example.

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And then we can use it again.

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Fill holes.

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Hair and size balls.

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And to task the hang new hang new wallpapers.

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So after the last line, the list has been created.

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So the p heat variable points to the first item in the list, and you can access any other item in the

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list simply by following the P next member from one list to the next.

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So you can compile the code, but there is no output as you see here.

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War says the code center is a memory leak, so the program has no code to delete the memory occupied

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by the task objects.

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So on the free store by the new operator here.

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So in the next lecture we're going to create that the later task list command in C++.

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So I'm waiting you in this lecture.