Data Structures MCQs with Answers
Practice important Data Structures MCQs with answers and explanations.
Multiple Choice Questions
Q241: What does the postorder traversal method print last?
- A: Root node
- B: Left subtree
- C: Right subtree
- D: The entire tree
View Answer
A
Q242: What kind of data structure is a binary search tree?
- A: Linear data structure
- B: Non-linear data structure
- C: Hash-based data structure
- D: Array-based data structure
View Answer
B
Q243: What does a recursive function call use to manage execution flow?
- A: Queue
- B: Stack
- C: Array
- D: List
View Answer
B
Q244: What is the first step in the preorder traversal of a binary tree?
- A: Print the value of the node
- B: Traverse the left subtree
- C: Traverse the right subtree
- D: Check if the node is NULL
View Answer
A
Q245: Which traversal method prints the value of the node after visiting its left subtree and before its right subtree?
- A: Preorder
- B: Inorder
- C: Postorder
- D: Level-order
View Answer
B
Q246: In a recursive function, what condition signifies the end of recursion?
- A: Node is not NULL
- B: Node has a right subtree
- C: Node is NULL
- D: Node has a left subtree
View Answer
C
Q247: What is the primary difference between recursive and non-recursive tree traversal?
- A: Recursive uses a queue, non-recursive uses a stack
- B: Recursive uses a stack, non-recursive uses a queue
- C: Recursive uses function calls, non-recursive uses an explicit stack
- D: Recursive uses a stack, non-recursive uses an array
View Answer
C
Q248: What does the inorder function do when it encounters a NULL node?
- A: Prints the value of the node
- B: Terminates recursion and returns to the previous node
- C: Continues traversing the right subtree
- D: Pushes the node onto the stack
View Answer
B
Q249: How does the preorder traversal visit the nodes in the binary tree?
- A: Node -> Left subtree -> Right subtree
- B: Left subtree -> Node -> Right subtree
- C: Left subtree -> Right subtree -> Node
- D: Node -> Right subtree -> Left subtree
View Answer
A
Q250: What is the output sequence of an inorder traversal on a binary tree?
- A: Root node value, followed by left and right subtrees
- B: Left subtree values, then root node value, followed by right subtree values
- C: Root node value, followed by right subtree and then left subtree
- D: Right subtree values, then root node value, followed by left subtree
View Answer
B