ShmoopTube

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Sorry And here's your shmoop du jour brought to you

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by a ray list looking for an array You khun

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dynamically resize it's a ray of hope want want which

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of the following methods successfully add an element to an

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array signs this crap over here that's Fine that code

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Over here you looked in and here your potential answers

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Okay here we go The purpose of this question seems

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to remind us of the difference between a plane all

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arrays and a ray lists they work the same way

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in a lot of respects but one of the biggest

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difference is the ability to dynamically resize array list While

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old school razor stuck with the side they're given forever

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this question featured in a ray list things would be

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over with pretty quickly Add to an array list we

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could just call the ad method toe add a value

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to it whenever we'd like no sweat but this question

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is asking us to do the impossible Add values to

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a regular array can't be done unless we're a little

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sneaky like option one so check this out option one

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takes it upon itself to create a new array that's

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one size larger Then it loops over the older ray

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grabbing his values and adding them to the new array

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once the loop finishes it adds the imager called lm

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which would be the imager provided with the method call

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to the end and returns the fresh new array very

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slick option one could be a used car salesman option

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Two seems simple enough thie idea seems to be to

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place the contents of the imager elem at the index

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corresponding to the total length of the array What this

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method is attempting is almost clever if only it worked

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Because all array indexes begin counting at zero the total

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length of an array does not correspond directly to the

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index values they're one off if you hadn't array with

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the length of five which is to say five total

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elements in it the array would be index from zero

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to four if you had a twelve element array zero

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to eleven and so on so this method is trying

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to provide a value for an array member who's index

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doesn't exist and will always be just one position out

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of reach You know what that's like in life story

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option two will keep throwing an array index out of

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bounds exception until the end of time So totally not

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gonna work and option three looks nice and simple That

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ad function looks very handy except that yeah again this

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isn't an array list ad calls like this one won't

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do a single thing for our array here that makes

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our answer A option One only like climbing over the

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fence when the gate was wide open Option one made

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it possible for us to do way more work than

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necessary to achieve something that could have been done more 00:02:36.78 --> [endTime] easily Another way Well want want

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