1. : What is the main purpose of tree traversal?
(A) To organize the tree
(B) To search for a specific value
(C) To visit all nodes in a tree
(D) To delete nodes
2. : Which traversal method visits the left subtree, the root, and then the right subtree?
(A) Pre-order
(B) In-order
(C) Post-order
(D) Level-order
3. : In which traversal method is the root node visited first?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
4. : What is the order of nodes visited in post-order traversal?
(A) Left, Right, Root
(B) Root, Left, Right
(C) Left, Root, Right
(D) Right, Left, Root
5. : Which of the following is true about in-order traversal of a binary search tree?
(A) It visits nodes in reverse order
(B) It produces a sorted sequence of keys
(C) It visits the root before the left child
(D) It cannot be performed on an unbalanced tree
6. : How does pre-order traversal help in creating a copy of a tree?
(A) It visits nodes in sorted order
(B) It visits the root before its children
(C) It captures the structure of the tree
(D) It requires less memory
7. : Which traversal method is typically used for evaluating expression trees?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
8. : What is the result of in-order traversal on the tree with nodes 1, 2, 3, where 2 is the root?
(A) 1, 2, 3
(B) 2, 1, 3
(C) 1, 3, 2
(D) 3, 2, 1
9. : In a binary tree, which traversal method can be used to print the nodes in reverse?
(A) Pre-order
(B) Post-order
(C) In-order
(D) None of the above
10. : What does the term “depth-first traversal” refer to?
(A) Visiting all nodes at the current level
(B) Visiting nodes from the top to the bottom
(C) Visiting nodes as deep as possible before backtracking
(D) Visiting nodes in a sorted manner
11. : Which traversal method uses a stack implicitly due to recursion?
(A) Level-order
(B) In-order
(C) Pre-order
(D) All of the above
12. : What is the output of a pre-order traversal on a tree with root A, left child B, and right child C?
(A) B, A, C
(B) A, B, C
(C) B, C, A
(D) C, B, A
13. : Which traversal method is best for printing a tree structure in a human-readable format?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
14. : How are in-order and post-order traversals different?
(A) They visit the root at different times
(B) They only visit leaf nodes
(C) They visit left and right subtrees in the same order
(D) They require different data structures
15. : What is the primary characteristic of level-order traversal?
(A) It visits nodes in a depth-first manner
(B) It visits all nodes at the current depth before moving to the next level
(C) It requires sorting of nodes
(D) It visits nodes in reverse order
16. : In which traversal method is the left child visited before the right child?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Both A and B
17. : What would be the output of a post-order traversal for a tree structured as follows: A with left child B and right child C?
(A) A, B, C
(B) B, C, A
(C) A, C, B
(D) C, B, A
18. : Which traversal method is least likely to be used in applications that require sorted output?
(A) In-order
(B) Pre-order
(C) Post-order
(D) None of the above
19. : Which traversal method can lead to a full listing of all nodes without regard for order?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
20. : What is the time complexity of tree traversals (in-order, pre-order, post-order)?
(A) O(log n)
(B) O(n)
(C) O(n log n)
(D) O(1)
21. : Which traversal would you use to get a prefix expression from an expression tree?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
22. : What is the output of an in-order traversal on a binary search tree containing the values 3, 1, 4, 2?
(A) 1, 2, 3, 4
(B) 3, 4, 2, 1
(C) 4, 3, 2, 1
(D) 1, 3, 2, 4
23. : What is the primary use of post-order traversal in binary trees?
(A) To create a sorted list
(B) To evaluate expressions
(C) To copy the tree
(D) To delete nodes
24. : What is the primary advantage of using a stack in tree traversal?
(A) It reduces memory usage
(B) It helps maintain the order of visits
(C) It allows faster access to nodes
(D) It eliminates recursion
25. : Which traversal method requires the use of a queue?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
26. : What is the order of nodes visited in pre-order traversal?
(A) Root, Left, Right
(B) Left, Root, Right
(C) Left, Right, Root
(D) Right, Left, Root
27. : How does post-order traversal affect memory usage?
(A) It uses less memory than in-order
(B) It can be implemented without recursion
(C) It typically requires more memory for stack
(D) It uses constant memory
28. : What traversal method is typically best for creating a balanced tree?
(A) In-order
(B) Pre-order
(C) Level-order
(D) Post-order
29. : What is the main difference between depth-first and breadth-first traversal?
(A) The order of node visits
(B) The data structure used
(C) The time complexity
(D) The number of nodes visited
30. : Which traversal method is suitable for constructing a binary tree from its traversal sequences?
(A) Pre-order and in-order
(B) In-order and post-order
(C) Level-order and pre-order
(D) Any traversal method
31. : What is the final output of a post-order traversal on a binary tree with nodes A, B, C?
(A) A, B, C
(B) B, C, A
(C) C, B, A
(D) A, C, B
32. : Which traversal method is most intuitive for hierarchical data representation?
(A) In-order
(B) Pre-order
(C) Post-order
(D) Level-order
33. : In the context of binary trees, what does the term “leaf node” refer to?
(A) A node with only one child
(B) A node with no children
(C) A node that is the root
(D) A node with two children
34. : Which traversal method would you use to create a postfix expression?
(A) Pre-order
(B) In-order
(C) Post-order
(D) Level-order
35. : How do you recognize the root node during traversal?
(A) It is always visited last
(B) It is always visited first in pre-order
(C) It is visited in post-order
(D) It can be determined by the left child
36. : What is the significance of using recursion in tree traversals?
(A) It simplifies the code structure
(B) It increases execution time
(C) It uses iterative methods
(D) It eliminates stack use