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‫Welcome back.

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‫In this video, we're going to check out lists which are a type of collection.

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‫And it's a flexible way to work with sets of objects or values other than an array, for example.

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‫So compared to your race to group of objects or values you work with can grow and shrink dynamically.

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‫And as you might remember in a race, you had to set that specifically.

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‫So it was set in stone.

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‫How many elements an array would have?

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‫But lists are quite dynamic here.

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‫A collection is a class and it requires an instance of the class before adding elements to that collection.

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‫So when we are working with lists, lists are collections.

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‫So lists is a type of a collection, so it's inheriting from it, but it's still a class.

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‫So we need to add the following line.

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‫So for collections that only contain one data type, use this system dot collections, dot generic namespace.

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‫So we will need to add this namespace to our project if you want to use lists list declaration examples

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‫here.

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‫So var numbers is equal new list int.

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‫So here we're talking about a list without any values.

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‫So it's an empty list at that point.

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‫And then below that you see an example where the list does have values.

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‫So the difference is here you add the values in curly brackets here, separated by a comma, then adding

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‫and removing values.

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‫So in order to add a value, you can simply use the add method.

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‫In order to get rid of a value, you use the remove method.

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‫So here we see we add the seven to our list and then we remove the seven from our list.

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‫Then we have an example of index.

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‫So index is zero and remove add index will remove an element at a specific position.

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‫So it's similar to an array where you have indexes and you can simply remove an element at a specific

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‫index getting a value.

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‫So here you see we have this numbers list which has one value which is 25.

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‫And now in order to get that value, we simply use the index.

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‫And in this case, because we only have one value, the index for it is zero.

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‫So numbers zero will be 25 and that will now be stored in a value.

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‫In order to clear a list, you can simply use the clear method.

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‫So there is a specific method dedicated to clearing the whole list so it will be empty afterwards.

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‫So it doesn't matter how many elements you have added, it will simply get rid of all of them.

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‫Of course, only specific to that particular list that we're talking about, lists and loops.

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‫So here you see an example of a list with plenty of numbers.

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‫So 5 to 40 each time, a five increment.

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‫And we use a for each loop here in order to loop through every single element in that list or a for

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‫loop.

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‫So you have both options here.

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‫The for each loop is a little bit cleaner as you can see here for each int element in numbers.

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‫And then we simply print out the element.

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‫And the same thing here for this for loop where we just check the amount of numbers of course as well.

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‫So you can see there is a property called Count that is available for every single list that you have.

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‫So in this case, we're just checking the amount of values that we have in that list in order to not

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‫run into an index out of bounds exception.

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‫All right.

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‫So this was an introduction to lists, and we're going to use lists later on.

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‫And I just wanted to show you how they work and what the main aspects of them are.

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‫Of course, lists have multiple more methods.

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‫So you can, of course, check those out, check out the methods and properties of lists and play around

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‫with them to get a better feeling for them and just create a handful of lists just to get into the habit

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‫of practicing.

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‫All right.

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‫So let's go ahead in the next video.

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‫See you there.