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Not let's look at an authority that you can go for straight rent while statement or why loop a while

2

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loop like a for loop is an education statement.

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You should use follow up if you know how many times to look otherwise you should go for it while.

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Why Lopez only condition expression on here is a general form.

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As long as a condition expression is true the body of y look keeps getting executed.

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So there is no initialization part.

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Similarly there is not an expression to all that can be included in the body offwell There is also a

8

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variation of vyle statement called blue eyed statement you would use it if the body of Weil must run

9

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at least once and here is the syntax.

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As you can see the body of Weil is followed by the condition expression so the body gets executed at

11

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least once subsequently the body keeps getting executed on the commission expression is false not do

12

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one statement and with the semicolon Otherwise you get a compilation error here's a good example where

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Deuel is used.

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Let's if you want to write some simple logic to perform some action based on user's input if you separate

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what's a positive number.

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We perform the action.

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Otherwise the user is asked to re-enter that number.

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So we need to first collect the input from user and then check if the input is positive or not.

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This can be achieved using a do look as shown here.

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The user input collection is done in the body and the while condition checks if and don't input is positive

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or not so if they use it and there's zero or a negative number then the while condition would be true

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and the user will be prompted to re-enter that number.

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This can be use under the user enters a positive number at which time the while condition fails on the

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intended action is performed.

25

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Not let's look at in finite look which basically loops infinitely.

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That is it loops forever.

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For example let's consider a company which wants to send marketing e-mails every morning at Adium and

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this can be achieved using a while loop as shown here that is a condition expression would always be

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true and hence a body of the while loop keeps repeating forever but with each iteration a check is made

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if the current time is 8 a.m..

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If that's the case then emails are standard by invoking sending mother.

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Otherwise we continue to look this can also be you'll be using a frontal lobe as shown here.

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As you can see to simulate an infinite loop.

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The parenthesis does not include any of the expressions.

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It includes all the semi-colons generally when implementing in fun I Cope's most people prefer while

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loops or follows a semantically while loops are considered to be more clear.

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However that's the case for infinite blocks.

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But in all other situations if both front and why Looks are applicable then a for loop is preferable

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.

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This is also recommended by one of the effective July dumps and will be discussed later on that's about

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it.

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That's all there is to why Lopes