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Welcome back to Learn to Code and JavaScript in this lecture.

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We're going to talk about looping.

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So with conditionals, we made logical decisions about which path we're going to take with looping.

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We make decisions about repeating code deaths.

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So essentially, we're going to do something repeatedly while a condition is true.

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So some examples of how we do looping, there's a for loop, there's a while loop in a do while loop.

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So here's some examples for Loop is more complicated than the ones with the word wild in them because

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a for loop, the first of all, there's a couple of different variations of for loops, but the most

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traditional basic for loop is a four letter.

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A variable started a value continue until it's reached a value and then add something to it each time.

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So in this case we're saying let ay equals zero.

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So we're going to set a variable ay to be the value zero and then we're going to start the loop and

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we're going to start the loop of is less than ten.

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And then at the end of the iteration we're going to do something and then we're going to increase the

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value of it by one with the plus plus and then we'll go back to the beginning and try again as I still

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less than ten.

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Yes.

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OK, so we'll do something that will increase the value of EI.

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So that's the most basic traditional for loop you can just for a loop so you can have a for loop inside

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of a for loop and think of this as two dimensions.

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So if you're going through every square instead of a larger square, you might be going across the column

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squares and you might be going down the road squares.

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So think of a bingo card, if you're remember with that, where you have a board that's broken into

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five by five squares and so you go across the the five in the columns and then down each one clear across

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all five as an example.

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And one of the key words you can use here is to continue.

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So what the continue does is say at this condition is true.

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Just continue with the loop, go back to the beginning and start again, essentially.

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So if the condition is true, we're not going to do the second something.

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And in this example, with the if there's a break statement that says, hey, if the condition is true,

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break out of the loop.

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And incidentally, you don't have to use this in conjunction with the condition, you could just say

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break and it wouldn't do the rest of the world or continue and would always continue back to the beginning

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at that point, which is most commonly done with enough.

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Those are the type of variation on the for loop, which is a form of with which lets you iterate something

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such as an array.

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So if we have an array with two, four, six, eight, 10, and I said let a equals that array, I could

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say let the of a.

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And then this is going to take on all the values in the array.

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All right.

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Let's take a look at the while loop examples.

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So the basic while loop just checks the condition at the beginning like an F check, the condition in

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it is true.

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It's going to keep executing.

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So you'd better do something to make it false eventually.

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So in this case, I'm saying if execrated zero, continue the loop and then we'll subtract one from

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X.

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So that started out as ten.

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It's going to be ten, nine than eight.

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And then once it gets down to zero, it's going to stop executing.

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The doodler is like the wild loop, it checks a wild condition at the bottom instead of the top.

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So you always enter the loop on the while loop, if the if X is starting value was zero, you would

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never enter the loop.

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But on the do you always enter the loop for at least one path?

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So let's take a look in visual studio code as some examples of looping.