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Hi everyone, let's do this question.

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You are given the head of a sorted singly linked list.

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Write a function that will take the given head as input.

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Delete all nodes that have a value that is already the value of another node, so that each value appears

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one time only and return the linked list which is still to be sorted.

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A sorted linked list.

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All right, so we are given a linked list, a singly linked list.

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And we need to delete all the duplicate values and return it.

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So that's the question.

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Now if you get this question in the interview feel free to ask any clarifying questions you may have.

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Now let's proceed and write some test cases to understand what the question asks us.

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And what's the expectation.

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Let's say the singly linked list which is given to us is this one.

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So we have a node with value one which is pointing to a node with value two.

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Again, that's pointing to another node with value two, and so on and so forth.

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So we can see that this is repeating right.

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And again over here we have the same value occurring three times.

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So if this is the input the output would be one pointing to two pointing to three pointing to four.

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And that points to null.

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So there is no repeating value.

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So that's what we need to achieve in this question.

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Now do give it a thought on how you could solve it.

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Now again remember the interesting thing over here is that the singly linked list is sorted.

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So that's mentioned in the question.

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So think about how you can make use of this also while you solve this question.