Data Structures MCQs with Answers
Practice important Data Structures MCQs with answers and explanations.
Multiple Choice Questions
Q501: What is the purpose of the BuildHeap algorithm?
- A: To insert elements one by one into the heap
- B: To build a heap from an unordered array
- C: To sort the array in ascending order
- D: To find the maximum element in the heap
View Answer
B
Q502: Which method is used to restore the heap order after deleting the root in a min-heap?
- A: percolateUp
- B: percolateDown
- C: insert
- D: deleteMin
View Answer
B
Q503: In the BuildHeap algorithm, why do we start with i = N/2?
- A: To process leaf nodes
- B: To process the root node
- C: To process internal nodes
- D: To start the heap construction from the end
View Answer
C
Q504: What does the percolateDown procedure do?
- A: Moves larger values up the tree
- B: Moves smaller values up the tree
- C: Moves smaller values down the tree
- D: Moves larger values down the tree
View Answer
C
Q505: What does the decreaseKey method do in a heap?
- A: Increases the value of the key at position p
- B: Decreases the value of the key at position p
- C: Removes the node at position p
- D: Restores the heap order after insertion
View Answer
B
Q506: What is the role of the increaseKey method in a heap?
- A: It increases the value of the key at position p
- B: It decreases the value of the key at position p
- C: It removes the node at position p
- D: It restores the heap order after insertion
View Answer
A
Q507: How does the remove method work in a heap?
- A: It directly removes the node at position p
- B: It decreases the value of the node to a very small value and then deletes the root
- C: It increases the value of the node to a very high value and then deletes the root
- D: It swaps the node with the root and deletes the root
View Answer
B
Q508: What is the primary use of the decreaseKey method in a priority queue?
- A: To increase the priority of an element
- B: To decrease the priority of an element
- C: To remove an element from the priority queue
- D: To add an element to the priority queue
View Answer
B
Q509: In the provided C++ code, what does the insert method do?
- A: Inserts an element into the heap while maintaining the heap order
- B: Deletes the minimum element from the heap
- C: Gets the minimum element from the heap
- D: Checks if the heap is full
View Answer
A
Q510: What is the purpose of the percolateDown method in a heap?
- A: To restore heap order by moving elements down
- B: To insert elements into the heap
- C: To build the heap from an array
- D: To remove the minimum element from the heap
View Answer
A