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A common requirement is to have a collection that can be an arbitrary size and can grow and shrink at

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runtime.

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So the C plus plus standard library provides a various classes to allow you to do this and will be described

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in next lecture, of course.

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But in this lecture we will create an examples that illustrates some of the principles of how these

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standard collections are implemented here.

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So in general, you should use the C plus plus standard library classes rather than implementing your

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own classes here.

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So further, the standard library classes encapsulate code together in a class, and since we have not

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covered classes yet, this in this lecture that we're going to create some code.

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In this code we're going to use functions that potentially can be called incorrectly.

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So you should regard this examples as just that example code here.

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So a linked list is a common data structure here.

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So these are typically used for queues where the order of items is important.

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So for example, a first in, first out queue, where the tasks are performed in the order that they

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are inserted in the queue here.

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So in this example, each task is represented as a structure that contains the task description and

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the pointer to the next task to be performed.

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So if a pointer to the next task is nullptr, then this means that the current task is the last task

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in the list here.

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So struct we're going to create a new struct here.

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Of course outside the here struct task here.

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And here we're going to task P next and.

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We can create another string here.

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Here.

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So recall this from the last chapter that you can access members of structure using the dot operator

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here so we can make it like that task that or let's create a task item and item that description here.

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As you can see, we can access their members.

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So in this case, the compiler will create a string.

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A string object initialized with the string literal.

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That means here we're going to initialize it with to something here.

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So and it will assign to the description member of the instance called item.

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So you can also create a task on the free storage.

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Using the new operator like that here, for example.

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Task P task and new task here.

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Oops.

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Uh, task.

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Here.

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And after using the object, after using the object object, you can delete by this.

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Delete.

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P task here.

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P task.

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So here in this case, the members of the object have to be accessed through the pointer and Cplusplus

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provides this operator here like that, the minus operator and the right, uh, greater than operator

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here.

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Uh, this operator gives you this access here.

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P task.

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P Task here.

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Description.

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As you can see here.

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And do something.

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Here.

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So here the description member here, here, The description member is assigned to the string.

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So not that the science task is a structure.

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There is no access restrictions.

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So something that is important with classes and described in next lecture here.

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So in next in this lecture, we're going to create some project that is going to.

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Use this task struct here.

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And, um.

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And we're going to make the strings and the task next pointers here.

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So I'm waiting you in next lecture.