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In this tutorial we will talk about the while loop a while loop is used to iterate over a block of code

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repeatedly until a given condition returns funds.

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And the main difference between the while loop and the for loop the do while loop.

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We are not certain of the number of times the loop requires execution on the other hand the default

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low.

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We know exactly how many times we need to run the loop and this is the syntax for the while loop.

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While condition and we have a set of statements in the body.

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So here is an example of a while loop the sine five to debatable a and using the while loop.

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I'm gonna check this condition if A is greater than zero.

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In that case the control goes through into the body or the Y loop but in S E and then the next line

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we're going to decrement the value of a by 1.

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The while loop get executed until this condition is found the while loop first prints out 5 and then

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four three two one that this is the output of the Y loop when the value of A is 0.

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Since 0 is none greater than 0 it comes out of the Y loop so the program first checks a given condition

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and if the condition returns filed the lupus terminated and the control jumps to the next statement

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and the program after the loop.

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So in the Jupiter note book I have executed the example that I have just demonstrated and this is the

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output.

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Next is the infinite loop a loop becomes infinite loop.

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If a condition never becomes false and you have to be careful while using a while loop because if you

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forget to incremental count the wearable in Python or right.

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Flawed logic the condition may never become false.

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In that case the loop and run in financially and the conditions after the loop will start to consider

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the same example that we have discussed the while loop.

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If I remove this particular line in the y loop A will always be five and it will always be greater than

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zero.

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And the program keeps printing the value of a

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so the condition never becomes false.

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And this result in a loop that never ends.

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So in my JUPITER KNOWN book If I comment on this line and execute this piece of code as you can see

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here the program is in an infinite loop to stop execution go to kernel and then choose interrupt not

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to stop execution.

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Next the else statement for while loop in a previous tutorials we have talked about using the L statement

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with the for loop and when we use the L statement with the for loop the L statement is executed when

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the for loop has exhausted ie iterating when we use an L statement with a while loop the L statement

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is executed then the condition in the while loop becomes false and the L statement is optional and it

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get executed if the loop i.e. iteration complete normally but not a word if the for loop or the Y loop

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does not end normally such as if we use a break statement or a written statement in that case the control

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will not go to the end clause.

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Consider this example we have assigned devalue Phi to the variable E and D while loop checks if A is

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greater than 0.

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If it is greater than 0 it prints out a decrement the value of a by 1 and then continues the loop until

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the condition is false.

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We have used the L statement with along with the while loop and after only when the while loop complete.

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Or when the condition becomes false only then the else clause gets executed.

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Let's execute this piece of code so as you can see until the condition is false do while loop word execute

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it and then finally the else clause is executed.

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Now let's consider then that example using the brake statement.

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Consider this piece of code we have used an L statement along with the Y loop the Y loop has a condition

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that it checks if the value of a is equal to 2.

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In that case it breaks the Y loop so let's execute this piece of code.

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If you notice the statement in the else clause is not executed this time that is because the while loop

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did not end.

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Normally it is terminated prematurely because of the brake statement here.

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This is about the L statement with while loop.