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C plus plus 11 introduce another way to use the for loop, which is intended to be used with the containers.

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So the C plus plus standard library contains templates for the container classes.

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These classes contain a collection of objects and provide access to those items in a standard way.

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The standard way is to iterate through a collection using an iterator object.

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More details about how to do it is will begin in the next lecture here, but this syntax requires an

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understanding of pointers and iterators so we will not cover them here.

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So the range based for loop gives a simple mechanism to access items in a container without explicitly

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using iterators.

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So the syntax is simple here for here, for loop.

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Here for declaration.

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An expression.

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And after that, the loop statement begins.

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Loop statement here.

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So the first thing is to pointed out that there are only two expressions and they are separated by the

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colon.

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So the first expression is used to declare the loop variable, which is of the type of the items in

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the collection being iterated throughout.

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And the second expression is gives an access to the collection in the C plus plus times.

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The collection that can be used are those that define a begin and end function that gives a access to

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iterators and also stack based arrays and the set based arrays that the compiler knows the size of.

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Here, the standard library defines a container object vector here in this here, let's create a vector

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and the vector template is a class that contains items of the type specified in the angled braces like

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that here vector.

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And we're going to create a string vector here.

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String vector.

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As you can see, we got an error because we have to include the vector library here.

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Import vector library, as you can see here.

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So we imported vector library and.

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So, you know, the vector is initialized in a special way that is new to a C plus plus 11.

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And this is called the list initialization.

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So this syntax allows you to specify the initial values of the vector in a list between curly braces

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here.

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So let's make an my cars variable and make it, for example, BMW, M.

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Fourth here.

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Portiere Fiat here.

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Volkswagen we're going to add here.

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Volkswagen.

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And we're going to add another Audi here.

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Here.

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And we're going to create a for loop for integer E.

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Zero.

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While Integer is less than my cast size and increase e by one and see out.

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Uh.

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Okay.

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See out my cars.

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Dot add e.

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And end line.

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And line here.

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So.

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Here.

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The vector class has a member of called member function called size that the called through the dot

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operator here which means the call this function on this object that returns the number of items in

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the vector.

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So each item is accessed.

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Using add function here.

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Passing the object index.

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The one big problem with this code is that it uses random access.

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That is, it accesses each item using its index.

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So this is a property of vector, but standard library container types do not have random access.

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Now we're going to create another range based loop here.

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Arranged baseball.

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This is going to be a range based loop.

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Based.

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Slope here and let's create the previous example we did here.

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So for string model, my car model.

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Oh, yes, my car model here.

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And my car's.

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And see out.

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My car model and inline.

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So.

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Let's print it again.

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And.

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Here say out.

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Uh, just to make.

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Make it look nice.

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Look here.

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Here.

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So this is the first example and this is the second.

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So actually the output is the same.

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They look, they look same, but each item is accessed using the add function here.

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But in this leg here, the we just use the range based loop here.

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So the standard library containers type, as I said earlier, do not have random access.

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And this for loop uses the range based for here.

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So actually we can create another work.

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So as you know, this type here works with any of the standard container types and for arrays allocated

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on the stack here.

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So we're going to create another here.

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Um, let's make it my car years here, my cars here.

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Here.

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And, for example.

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Um.

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2002.

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2005.

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1989.

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Okay.

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And how many?

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Yeah, we have five.

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Let's create a five to make it.

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Which are we going to print it here or make it for where you want to?

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Uh, you want access here.

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And 2010.

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So and let's print it out using this range based for.

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For loop here, for integer.

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Uh, here, here.

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And my cars here and here.

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C out my here and.

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And line.

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Here.

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As you can see, we printed this as well.

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In this case, the compiler knows the size of the array because the compiler has allocated the array

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here.

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And so it can determine the range.

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The range based for loop will iterate through all the items in container.

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But as with the previous version, you can leave the for loop using the break, return, throw or go

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to here.

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So and you can indicate that the next loop should be executed using the condition continue statement

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here so we can make it like that here.

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Okay.

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If.

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Make it.

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Let's make an if statement.

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Write an if statement here.

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So.

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If our year equals to two 1989, make it just an.

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Okay?

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No, actually.

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It.

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Uh, the year car is too old.

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See out.

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Car is to.

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All.

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Old classic.

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We'll make it classic car.

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And of course, we have to end line here to make it look nice.

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And else here, just print the year of the car here.

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Make it here.

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As you can see here, when it comes to the 1989, it shows the if statement is executed and else the

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C out here is just printed to the screen here.