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Hi everyone, let's do this question.

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Given an array, rotate the array to the right by k steps where k is non-negative.

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So that's the question.

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Now over here we have an example.

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Let's say the array which is given to us is 1234 over here.

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And if k is equal to one then we have to do one rotation to the right right.

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So that will give us 4123.

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So you can see that this four over here actually came was rotated to the right.

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And because there's nothing over here it came over here.

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Right.

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So we have 4123.

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Now if you do one more rotation that is if k is equal to two then we have after one rotation we have

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4123.

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And then this three comes over here right.

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So this comes over here and we get 341 and two.

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So that is what we call right rotations.

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So this is the question which we have over here.

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Now remember in the interview when you get this question always feel free to ask clarifying questions

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so that you thoroughly understand the question and you and the interviewer are on the same page.

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So for example, a sample question that you could ask over here is what happens if an empty array is

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passed.

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So in this case let's say the interviewer replies return an empty array in this case.

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All right.

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Now another question is if k is equal to zero no rotation is to happen.

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Is that correct.

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And then let's say the interviewer replies yes.

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So you have got a good understanding of the question.

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Now let's go ahead and write a few test cases.

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Now remember in the interview you can always ask the interviewer, is it okay if we come up with a few

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test cases together.

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So this will ensure that you are on the same page with the interviewer.

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Now let's go ahead and make a few test cases over here.

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If the given array is one comma two, and if k is equal to one, then we're just doing one rotation

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right.

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So this two comes over here and we get two comma one as the output.

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Now in this case if k is equal to two we do one more rotation and we get back to one comma two.

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All right.

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Now let's say the given array is 1234 and k is equal to three.

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Right.

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So in this case what will happen after one rotation.

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We will have 412 and three.

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After the next rotation we will have 341 and two.

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And after the third rotation we will have 234 and one.

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So this would be the case.

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Now in this same case if k is equal to zero then we wouldn't do any rotation.

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And the array is still one, two, three and four.

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So that's clear.

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And if an empty array is given and let's say k is equal to two, we just return the empty array.

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So we have got a good understanding of the question.

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And we have written our test cases in the next video.

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Let's think through how we can solve this.

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And let's also look at the complexity of analysis of the solutions that we come up with.