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‫Hello and welcome.

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‫In this lecture, we're going to be looking at an even cleaner syntax for for loops which we use specifically

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‫when dealing with arrays or collection types.

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‫Let's dive in and see how it looks.

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‫So this pattern of iterating over all the actors in an array is so common that we actually have our

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‫own type of for loops specifically designed for this purpose in C++.

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‫So the basic format of this for loop, it's called a range based for loop works like this.

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‫So we start with the same keyword, we have some opening parentheses, but then instead of having these

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‫three statements, we do the following we create a variable to store the pointer or the thing within

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‫the array that we are looping over.

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‫So in our case it would be an actor pointer, which we can call the actor.

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‫Then you put a colon and then you put the array.

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‫So that would be actors.

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‫So the way this reads is essentially for actor, star, actor in actors.

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‫And what that's going to do is it's going to loop over every actor star that is in the t array.

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‫Now, this doesn't only work with T arrays, it works with all sorts of different collection types.

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‫We call them collection types because they are types that contain multiple of a certain type.

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‫So this is very useful because now we've got in each iteration of our for loop a pointer to a different

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‫actor from the array and it's just a lot cleaner and simpler and easier to read than the for loop above.

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‫So I'm not going to give you a challenge slide here.

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‫I just want you to convert from using this three statement for loop to using the range based for loop

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‫instead and test out your findings for the video and have a go.

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‫Okay.

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‫Welcome back.

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‫So I'm going to copy over this body and what am I going to need to change?

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‫Well, instead of accessing the array directly with an index, we now have our actor pointer variable.

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‫So we can just use actor, get actor, name or label.

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‫That's the actor name and that's what we're printing out now.

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‫We can get rid of the old for loop.

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‫We no longer need that and we can go ahead and compile.

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‫Once it's done.

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‫Let's go ahead and hit play, grab a gargoyle and go and step inside.

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‫And sure enough, it's printing out the gargoyle statue and the beep player when we're both in the alcove.

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‫Great stuff.

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‫I'll see you in the next lecture.