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Hello welcome to this video.

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In this video I'm going to introduce you to while loop statements in Python while loop statements are

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the type of statements that you add to your code.

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If you want certain aspects of your code to run continuously based on certain conditions that are true.

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One thing you need to be careful of with the while loop is that you must make sure that the condition

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will eventually become false if not be called will continue to run and run and it becomes an infinite

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loop.

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So you need to set it up in a way that the loop can be terminated when the condition becomes false.

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You can also use an else clause on L statement inside your while loop so you can wrap the else statement

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inside a while.

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Look this is what a basic syntax looks like for a while loop.

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You basically have the wow and then you set the condition and then you have the code that will execute.

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So let's create a while loop statement to 18 an index variable a variable that the while loop will use

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to get started.

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So I'm going to create a variable and when I call it I and I'm going to give it a value of 1.

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So now that I've got the initial variable set this is a variable that the while loop will work with.

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So you start the while loop by using the keyword.

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Wow.

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Then you specify the variable which is I.

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So I'm setting the condition.

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Now I'm saying while I wish I said to 1 while it is less than 7 I'll add my colon.

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Then I will specify what I want to happen.

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So this is the code that execute is going to print.

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I on the screen now the way the code is at the moment.

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If I stop here this will become an infinite loop.

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That means it will keep running and it will never stop because as it is now the condition will always

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be true because I will always be less than seven.

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So what I need to do I need to use an increment operator to keep increasing the value by one.

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So each time the loop goes round I wanted to increase it by one until it's becomes less than seven.

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So what I need to do here I need to see I which is the variable i need to add plus equals to.

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OPERATOR What this operator would do a tool each time the loop goes round.

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It will add one to it each time on till this condition becomes false.

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So if he keeps going around and adding one eventually this will become less than seven and then the

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loop will terminate and jump out of this block.

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And that will end the loop.

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But if I don't put this bit on line five then the code on line three and four will keep running and

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never stop.

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It will become an infinite loop.

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There is something that you always have to be careful about when you are using a while loop.

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You need to make sure that at some point the code will become force.

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That is the condition we become.

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So what will happen now if I play this code.

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It will print out one to six.

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I've got my code saved.

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I'm just going to play the code so you can see the output.

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What should happen this code here on line 4 will print the numbers 1 2 6.

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It will not print seven because the condition says as long as while this variable i is less than seven

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I wanted to print I saw what this code on low five does each time the loop goes round.

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It will add one to it until it gets to six.

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It then terminates the loop because the condition no longer becomes true.

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So let me play that click play and if you look here we can see inside my console I'm printing the number

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one two three four five and six.

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It doesn't print seven.

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So that is the condition I have set.

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As long as i is less than seven I wanted to print i.

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So each time it goes round your prints one because that one is initial.

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It goes round the loop again.

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It repeats and I had one here.

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He prints to it does the same thing again.

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Each time it goes round it will print the number that has been added to the original value.

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So that's basically how the while loop works.

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But be careful when you set it up a while loop.

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Make sure that it will eventually terminate by evaluating the condition you have set to be false if

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you have a wild look.

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That condition is true all the time be called will not X will not terminate.

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It will keep running and running and running and running.

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So you really do not want that.

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So that's it for this video on while loop statements.

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Thanks for watching.

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Bye for now.