All language subtitles for 12. While Loops How and Why

So you learn that a for loop iterate through a container which could be a list, or a string, or a tuple.
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And the loop will terminate when the container is exhausted.
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So for example it prints out one, two, and three.
And when there are no more items
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the loop ends.
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So a full loop runs until a container is exhausted and a while loop a while loop runs as long as this
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condition is true.
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Let me execute that and see what is going to happen.
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So you will see that 1 is being printed out all the time.
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So if I scroll up here I will not be able to find where the starting point was because there's a million
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ones now being printed out there every split of a second.
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So what's going on here is that a while loop, while is a keyword, and then that is followed by a condition.
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In this case the condition is that A is greater than zero which is true.
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So A is actually 3.
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That means this condition is true.
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And as long as this condition is true, this will be printed out, so under the while loop you can have
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as many actions operations as you want.
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For example let me interrupt this with control C on your terminal.
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And then add another line here print2, save, execute.
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So 1 2, 1 2, 1 2, 1 2, 1 2
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is being printed out.
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Okay I'll interrupt that.
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Not the rate that these numbers are being printed out
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depends on your computer.
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Processor speed.
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So the faster your processor, the faster you will get these action here,
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these operations being executed.
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Now of course this will always forever be true because it's a just a static declaration of a variable
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here.
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So no one is changing it here, therefore of a condition will always be true.
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You can see inside Python when you check something like 3 is greater than 0 you get true.
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So this is basically while True, and you will sometimes see it like that.
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So just delete the first line.
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Exit here, execute the code again.
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So again the same thing happens because true is always true.
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However, this is not how while loops are used in real world.
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It's meaningless to check if true is true and print out something all the time.
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So let me go ahead and explain while loops in a better example in the next video.