Binary Trees & BST Quiz

8 questions12 minPass: 60%+10 XP on first pass

Traversals, DFS vs BFS, height, diameter, LCA and validating a BST.

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Question 1
For this tree, what is the INORDER traversal? (type the values separated by spaces)
```
        1
       / \
      2   3
     / \
    4   5
```
Question 2
For the same tree, what is the PREORDER traversal?
Question 3
What is the maximum depth (counting nodes) of that tree?
Question 4
Which traversal of a Binary Search Tree visits values in sorted order?
PreorderInorderPostorderLevel order
Question 5
Which data structure does level-order (BFS) traversal use?
QueueStackHeapHash set
Question 6
Why is checking only left.val < node.val < right.val NOT enough to validate a BST?
Every node must also respect limits set by all its ancestors, not just its parentBecause BSTs can't have negative valuesBecause it's too slowIt is enough
Question 7Select all that apply
Which tree questions are usually solved with DFS returning a value from the children (postorder)? (select all that apply)
Height of the treeDiameter of the treeCheck if the tree is balancedRight side view
Question 8
What is the time complexity of visiting every node of a binary tree with n nodes?
O(log n)O(n)O(n log n)O(n²)