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Let's do this question.

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Given the root of a binary tree.

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Imagine yourself standing on the right side of it.

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Return the values of the nodes you can see ordered from top to bottom.

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So this is the first question.

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The second question is given the root of a binary tree, imagine yourself standing on the left side

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of it.

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Return the values of the nodes you can see ordered from top to bottom.

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So this is the same question.

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Just in the first case, you're standing on the right side, and in the second case you're standing

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on the left side.

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So let's see how we can solve this.

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And let's first try to understand the question.

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Let's say this is the binary tree which is given to us.

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And let's say we are standing on the right and we are looking at the binary tree in this direction.

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So we can see these nodes.

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Right.

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We can see four, we can three, we can see three, seven, five and 12.

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We cannot see one because it's blocked by this.

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Three because these two are in the same level.

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Similarly we cannot see two and eight because it is blocked by seven, because all these three are in

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the same level.

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And then we can see five and 12.

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So this is the right side view of this binary tree.

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So for question one the output should be an array with these values which is four, three, seven five

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and 12.

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Now for question two we are looking at this binary tree from the left side.

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So that's in this direction.

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So the nodes that we can see are these right.

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So we can see 4125 and 12.

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We cannot see three because it's blocked by one.

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We cannot see eight and seven because it's blocked by two.

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And we can see five and 12.

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So the output array for question number two should be 4125 and 12.

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So this is the question.

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Now let's proceed and take a look at a few test cases.

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Now let's say the binary tree which is given to us is having just one node.

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So in this case even if we look from the right or from the left, we will just see that particular node.

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So the output should be just an array with that particular value.

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Right.

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And if we are given a null null binary tree where the root itself is null in this case we will just

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return an empty array.

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And remember in the interview you have to come up with test cases together with your interviewer to

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ensure that both of you are on the same page.

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And then we have already discussed this case where this is the binary tree which is given to us.

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Now, if you look from the right, you can see four, three, seven, five and 12.

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So this is the output.

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And if you look from the left you can see four one, two, five and 12.

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So this is the output.

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So this is the question.

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And we have looked at a few test cases.

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