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Hi everyone, let's do this question.

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Given an integer array of unique elements, return all possible subsets.

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The power set.

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This is called the power set.

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The solution set must not contain duplicate subsets.

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Return the solution in any order.

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So this is the question.

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Now let's try to understand this.

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We have to return all the possible subsets of the given array.

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So that is what is mentioned in the question.

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And that is called the power set.

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Now for example, if the array which is given to us is one comma seven, this one over here, then the

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power set will be all the possible subsets.

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So we have an empty array over here which is a subset.

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Then we have only one only seven.

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And then we have one and seven.

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So you can see we have four subsets which are possible and the set of all the possible subsets.

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This over here is called the power set.

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So again that's the question.

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We will be given an array.

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And we have to return the power set of that array.

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Now over here also notice that we can return the solution in any order.

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So that means that we can either write one 7 or 7 comma one.

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So it does not matter.

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So the order does not matter when we create the power set.

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All right.

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Now let's go ahead and try to understand this better by writing a few test cases.

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Now remember in the interview try to talk to the interviewer and you can ask the interviewer whether

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he or she is okay, that whether you both could come up with the test cases together.

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So that will ensure that you have a thorough understanding of the question.

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Now let's proceed.

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Let's say the array which is given to us is one, two and three.

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Now let's go ahead and write the power set or all the subsets of this possible array.

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Now there is a a subset where the array is empty right.

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And then I could have arrays of length one.

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So I just take one I just take two and I just take three.

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Now I can have subsets where I take two elements right.

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So I could take one and two, one and 3 or 2 and three.

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And finally I can have a subset where I have all the three elements.

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So I can have one, two and three also.

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So these are the eight possible subsets which I can have when the array which is given to me is one,

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two and three.

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All right.

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Now let's take a few more cases.

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What if I'm given an array with only one element.

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Let's say nine.

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In this case I can have a subset which is an empty array.

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And I can have a subset which has only nine.

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And what if I'm given an empty array?

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Then the power set will have only one element right?

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And that itself will be an empty array.

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So this is a few test cases that gives us a good understanding of the question.

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Now in the next video, let's try to think through how we can solve this question.