WEBVTT

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We introduce the wildy last time which is really the only loop we need.

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But today I want to go over a slight variation of the while loop and it's called the do while loop.

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So here's how you write a do while loop.

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So you have to do which is a key word and you have the statement blanks on your statements here and

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you have the while condition actually at the end not the beginning like the while.

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And you have a semi-colon.

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So this is very important.

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Don't forget the semi-colon otherwise it will complain.

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So this really is like an inverted Waialua And no you you do need the semi-colon unlike B the regular

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white loop.

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You didn't there was no semi-colon before so you may ask what the differences between a while loop and

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a do while loop and it's really when the condition is checked.

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So a while loop will check the condition first before anything happens.

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And the do while loop will check the condition after the first iteration has completed so it will actually

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go and say Do you really just doesn't do anything actually.

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And it was sort of passed through there and actually just start doing all of the statements in the do

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while loop and then at the after the last statement then it will check the condition.

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So again this is very much like the exact opposite of the while loop or inverted while loop.

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So it's kind of see the difference in action.

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So let's just actually get rid of this and say it goes to one and conc in smacks

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goes to zero and we're going to say while it is less than or equal to Max

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in printout so in the wild

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This K and then we're going to write a do while as well and say the same condition.

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The semi-colon very important for the do while loop.

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And we're going to s.c out

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the two while

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are going to write this and this.

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That's all it printed out is in the do while loop.

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So somehow I had Max to be zero and 1 is not less than or equal to max so it checked the condition for

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this while loop first.

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Like I said and this evaluates to false of course.

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Right.

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So it didn't do any iterations of this while but it did do it one iteration of the do while loop.

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So that's really the difference between the two the do while loop will always check the condition last

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and the while loop will and will check the condition first.

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That's really the main difference.

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And you may be asking why would you want such a loop.

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Why.

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Why even have this.

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Well I'll be showing you an example of why you'd want to use this in one of our upcoming lectures.

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They'll have to do with input in fact.

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So next time going to go over last looping structure called the form.