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Welcome back. Break and continue are two special kinds of

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statements that can be used within while or for loops.

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A break statement breaks out of whatever loop contains it.

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So here, if we're within a loop and we encounter a break statement,

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then Python is going to break out of the loop immediately.

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So, this break statement is going to say that the program should jump

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from here to here and it's going to

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skip the rest of whatever is in the body of the

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for loop and it's not even going to check the condition again.

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A continue statement is similar.

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A continue statement like

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a break statement does skip whatever is in the rest of the loop.

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So, it's not going to run this code,

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but unlike a break statement which takes us to the bottom of the loop,

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a continue statement instead says to continue at the top

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of the loop and so it's going to check this condition once more.

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So, let's see what break and continue statements do in code.

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So, here we have a while loop,

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this condition is true meaning it's always going to be, well, true.

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So, what that means is that without a break statement,

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then this is almost by definition going to be an infinite loop.

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But, here in the body of the loop,

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we first print out this,

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this phrase will always print and then we call break and then we

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say print does this phrase print and then here we print out,

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we're done with the while loop.

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So, I want you to think a little bit about what this code is actually going to print.

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So, what I expect to happen is that when we run

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this code even though this says while true,

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this is only going to print out once because after this prints out,

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then we break out of our while loop.

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Then, we skip what's here because that comes after

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the break and then we print out we're done with the while loop.

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So, I expect this and this to print out.

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Let's run our code to be sure that's the case.

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So, you can see the only things that print out are this statement and this statement.

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Now, what would happen if I replace the break with a continue.

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So, when I run this code,

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what I should expect is that it's going to get stuck in an infinite loop.

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The reason is that, we are online to print out this phrase will always print and then

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this continue statement jumps to the top of the loop and checks the condition again,

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and here this condition again by definition is going to be true,

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and so we're going to print this out again and then

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continue and so we have an infinite loop and I expect

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this phase will always print to read printed out

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while a huge number of times before our program actually stops terminating,

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and you can see when we look at our code,

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but that's exactly what happened.

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So, let's look at another example to see how a continue statement works.

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So, here we have a slightly more complicated piece of code.

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We have a number x,

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which we set to zero,

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and then we say while x is less than 10,

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and as long as x is less than 10,

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we print out we are incrementing x.

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Now, what we do is we say,

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if x is even so in other words if x modulo two is zero,

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then we add three to the value of x.

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So, x would jump from zero to three,

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and then we say continue,

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which takes us back to the top of this for loop Then,

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we say, if x modulo three is zero,

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in other words, if x is divisible by three,

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then we assign x to be x's value plus five and almost regardless,

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then we add one to x.

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By the time we're done,

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we print out done and we print out the value of x.

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Now, let's run this code and CodeLens to see what happens.

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So, again we start x is zero and we say while x is less than 10,

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print out we're incrementing x.

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Here x is divisible by two,

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so x is going to jump from zero to three.

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Now, again, when we hit this continue statement,

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we're going to go to the top of this while loop.

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So, we jump back up to the top,

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we ask is three less than 10? Yes it is.

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In this case three is not an even number,

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so we check is it divisible by three,

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which it is and so we add five to x and then we add one more on the x,

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and so x ends up with the value nine,

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nine is less than 10,

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so we print out we're incrementing x,

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nine is not even,

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but it is divisible by three,

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so x gets the value 14 and then 15 and then now when we check our condition,

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15 is not less than 10,

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so we say we're done with our loop and x has the final value of 15.

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So again, here we use the continue statement

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to ensure that we aren't going to run what was in the rest of this loop,

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we instead jumped to the top of the while loop.

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That's all for now, until next time.