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Hey there.

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Welcome back.

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Let's now take a look at a very famous coding interview question called combinations.

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So the question reads given two integers n and k, return all possible combinations of k numbers chosen

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from the range one comma n.

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So let's say n is equal to four and k is equal to two.

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So in the example that's given to us, we have to form all possible combinations of two numbers from

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the range one comma n which is 1234.

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So notice over here we have one comma two one comma three one comma four, two comma three, two comma

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four and three comma four.

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So these are all the possible combinations that can be made which consist of two numbers from the range

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one comma four.

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And then the question also says that you may return the answer in any order, which means that one comma

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two will be treated as the same as two comma one.

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So we have understood the question.

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And again, remember in a coding interview, it's important that you ask the interviewer any clarifying

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questions which you may want to ask.

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So for this question a possible clarifying question could be will k be less than n at any point?

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Because in that case that would be a problem.

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What if n is equal to four but k is equal to ten?

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Let's say to this question, the interviewer replies no, k will always be between one and n, both

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inclusive.

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All right.

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So we have understood the question, and we have asked any clarifying questions that we may want to

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ask.

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Now in the next video, let's think through the approach that we can take to solve this question.