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OK welcome back.

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So as I mentioned at the end of the last video on iterating through an array with four loops and four

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inches this is going to be a very quick exercise.

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There's only one here and all you need to do is evaluate this code.

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So we have two arrays and we're doing a for each.

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So take a moment try and walk through this mentally or remember what we talked about how foreach works

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how it's different than a for loop what array iteration is.

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All of that and take a moment to think about what this prints out and then we'll go over it.

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All right.

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So puzzle video don't cheat.

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OK great.

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So let's take a moment first to appreciate how impressive that animation was.

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Here let me show it to you again and I can even change colors.

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And there's a few more animations Tim's like you're not really that impressed.

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So let's just talk about the solution I guess.

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So to arrays numbers which is an array of numbers going from one to 10 and colors are all colors array

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red orange yellow and green for strings.

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Then we're running numbers dot for each.

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And I tried to confuse you a little bit where I threw a few wrenches in here where we have the variable

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name color which is not a good name for this for each because we're not dealing with colors.

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We're running for each on the numbers array.

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So we're running foreach on this array and it takes this whole function right there.

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And it applies it to every single item in this array.

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So in this case 10 different numbers.

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And again recalling that temporary variable name the placeholder color but it's going to be referring

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to numbers in our case but it doesn't actually matter as far as JavaScript concerned.

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This is just like any other function argument that we declare that we write it can be named whatever

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we want as long as it follows the basic rules of javascript where it's a valid name for a variable.

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And then I threw a little Maggiolo in here so if color mod 3 is equal to zero.

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So what that means is that the number needs to be evenly divisible by three.

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If that's the case then we print out color which is actually a number.

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So loop through all of them.

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This will be run but only on a few of them will this constant out log be executed.

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So the numbers that are divisible by 3 are 3 6 and 9.

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So we would expect to see 3 6 and 9.

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And just to walk you through that first few numbers.

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First time through this code is called with 10:01 as color.

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So color is equal to 1 if color mod 3 is zero.

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That's false.

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So we're done then.

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For each does the same thing with two.

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And it passes two into this function as color.

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So color mod 3 that's also not equal to zero.

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So we don't don't like it.

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And then next this is the last and I'll do three is passed in to this function.

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So colors three three my three is zero.

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So we find they print out colored.

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So let's copy this up and evaluate the whole thing and we get 3 6 and 9.

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Awesome.

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So that's all we need to do here.

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Quick exercise.

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I made it a little bit tricky.

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What would be a good practice for you.

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Another good exercise is to go through and just rewrite this code that will only print out 3 6 and 9

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.

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Only the numbers that are divisible by three.

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So not just always 3 6 and 9 but if we had 50 items in this array it should always print out the ones

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divisible by three but use a for loop rather than for each.

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So rewrite or translate this code into a for loop.

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Great.

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I'll see in the next video where we return to our To-Do list and we implement a re iteration