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Conditional loops.

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In the previous section, we gave a controversial example where the condition in the for loop pulled

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from the data.

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In this example, there is a null variable used in this condition.

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This is a candidate for the while conditional loop here.

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So while here.

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Okay, let's make it like that.

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My data bull my data and make it true.

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Here and while my data here then integer here my data or we can make it into here.

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Okay bull here my data and STD.

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STD or C out E here and N line here.

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As you can see, it created and printed a bunch of ones here.

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So this means true here.

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This statement will continue to loop until the expression, um, has a value of false here.

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So as with four you can exit the while loop with brick return true or go to keywords and you can indicate

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the next loop should be executed using the continue statement.

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So the first time the while statement is called the condition tested before the loop is executed.

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In some cases you may want to you may want the loop as good at least once and then test the condition.

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So most likely depended upon the action in the loop to see if the loop should be repeated.

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The way to do this is to use do while loop here.

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So now let's make it my data false.

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Pulse.

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Here.

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As you can see, we printed nothing.

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But if we do the do while loop for example, do do here.

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Uh.

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Okay.

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Is she out e here or my data here?

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And line.

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And.

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We're going to add the file here while my data.

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Here, as you can see here.

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So let's print it out.

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As you can see here, it printed zero because the with the do while loop the do condition here do code

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here has to be executed at least once.

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So this executes and when when our code tries to find out if my data is true or false, it returns the

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false.

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And that's why it printed only once here.

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But in this case, it printed no nothing here.

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So the, uh, here semicolon after this is required here, this is a class.

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So, uh, as you can see here, this loop printed, uh, once here, false, despite of my data having

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false here.

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So the difference between two types of loop is that the condition here, the condition is tested before

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the loop is executed in the while loop.

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And so the loop may not be executed in a do while loop.

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Here the condition is called after the loop, which means that with a do while loop, the loop statements

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are always called at once.