Data Structures MCQs with Answers
Practice important Data Structures MCQs with answers and explanations.
Chapter: 12
Q221:
Which function of the TreeNode class sets the right child pointer?
A. setRight()
B. setLeft()
C. getRight()
D. getLeft()
Correct Answer:
A
Chapter: 12
Q222:
How is the TreeNode class designed to handle different data types?
A. By using explicit type declarations
B. By using a template class
C. By using multiple inheritance
D. By using type casting
Correct Answer:
B
Chapter: 13
Q223:
What is the main advantage of using a binary search tree (BST) over a linked list for search operations?
A. Faster search times
B. More memory-efficient
C. Easier to implement
D. Simpler traversal
Correct Answer:
A
Chapter: 13
Q224:
In a binary search tree, where are nodes with values less than the root node placed?
A. Right subtree
B. Left subtree
C. Root node
D. None of the above
Correct Answer:
B
Chapter: 13
Q225:
What is the maximum number of comparisons required to find a number in a binary tree of depth 20?
A. 10
B. 20
C. 30
D. 40
Correct Answer:
B
Chapter: 13
Q226:
How is the depth ddd of a complete binary tree with nnn nodes calculated?
A. d=log2(n)d = \log_2(n)d=log2(n)
B. d=log2(n+1)−1d = \log_2(n + 1) - 1d=log2(n+1)−1
C. d=nlog2(n)d = n \log_2(n)d=nlog2(n)
D. d=n2d = \frac{n}{2}d=2n
Correct Answer:
B
Chapter: 13
Q227:
What is the time complexity of searching in a linked list with nnn nodes?
A. O(logn)O(\log n)O(logn)
B. O(n)O(n)O(n)
C. O(1)O(1)O(1)
D. O(nlogn)O(n \log n)O(nlogn)
Correct Answer:
B
Chapter: 13
Q228:
What does the preorder traversal method in a binary tree do?
A. Prints the left subtree, then root, then right subtree
B. Prints the root, then left subtree, then right subtree
C. Prints the right subtree, then root, then left subtree
D. Prints the root, then right subtree, then left subtree
Correct Answer:
B
Chapter: 13
Q229:
In which traversal method are nodes printed in sorted order in a binary search tree?
A. Preorder
B. Inorder
C. Postorder
D. Level-order
Correct Answer:
B
Chapter: 13
Q230:
What will be the output of the inorder traversal of a binary search tree?
A. Nodes in reverse sorted order
B. Nodes in random order
C. Nodes in sorted order
D. Nodes in the order they were inserted
Correct Answer:
C
Chapter: 13
Q231:
What type of traversal prints nodes as: left subtree, right subtree, root?
A. Preorder
B. Inorder
C. Postorder
D. Level-order
Correct Answer:
C
Chapter: 13
Q232:
Which C++ function call prints the node value before traversing its left and right subtrees?
A. preorder
B. inorder
C. postorder
D. levelorder
Correct Answer:
A
Chapter: 13
Q233:
In a complete binary tree with 100,000 nodes, what is the approximate depth?
A. 10
B. 15
C. 20
D. 25
Correct Answer:
C
Chapter: 13
Q234:
How does recursion work in the preorder traversal method?
A. Calls itself on the left subtree before printing the node value
B. Calls itself on the right subtree before printing the node value
C. Prints the node value before calling itself on the left and right subtrees
D. Calls itself on the left subtree and then the right subtree, printing after returning
Correct Answer:
C
Chapter: 13
Q235:
What does the postorder traversal method do?
A. Prints the root, then left subtree, then right subtree
B. Prints the left subtree, then right subtree, then root
C. Prints the right subtree, then left subtree, then root
D. Prints the root, then right subtree, then left subtree
Correct Answer:
B
Chapter: 13
Q236:
What is the result of the following preorder function execution?
A. It prints nodes in postorder
B. It prints nodes in the order of insertion
C. It prints nodes in preorder
D. It prints nodes in inorder
Correct Answer:
C
Chapter: 13
Q237:
What is the primary benefit of using a complete binary tree compared to a linked list in terms of search efficiency?
A. Faster search times due to fewer comparisons
B. More memory-efficient
C. Easier to implement
D. Better for sorting
Correct Answer:
A
Chapter: 13
Q238:
How does the find method differ from the insert method in a binary search tree?
A. find checks for duplicates before insertion
B. find only searches for a number while insert adds a number
C. find prints the tree structure
D. find traverses in reverse order
Correct Answer:
B
Chapter: 13
Q239:
What is the depth of a binary tree with 1,000,000 nodes?
A. Approximately 10
B. Approximately 15
C. Approximately 20
D. Approximately 30
Correct Answer:
D
Chapter: 13
Q240:
In the inorder traversal, which subtree is processed first?
A. Right subtree
B. Left subtree
C. Root
D. Both subtrees simultaneously
Correct Answer:
B