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Hi everyone, let's do this question.

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Given the root of a binary tree, invert the tree and return its root.

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Invert means swap every left node for its corresponding right node or get the mirror image.

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So for example, if this is the binary tree which is given, you can see that these two are swapped.

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So we have three and two over here.

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Now these two are swapped.

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So we have five and four over here.

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This is the left node right of two.

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So but over here you can see this has become the right node of two.

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Similarly these two are also swapped.

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And we have instead of six and seven we have seven and six.

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So this is the question.

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

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We've already seen that if this is the tree which is given to us, we have to get this as the output.

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Now if this is the tree over here, you can see this is null, right.

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So in that case over here this would be seven and null.

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So that's the only difference between these two.

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And then if you are given a tree with only the root then the mirror image or the uh the case where we

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swap the corresponding left and right uh nodes will also have will be looking the same.

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Right.

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So if this is given, then the output also will be just a tree with one node.

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All right.

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So this is the question that we are trying to do.

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We have understood the question and we have written a few test cases.

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