Data Structures MCQs with Answers
Practice important Data Structures MCQs with answers and explanations.
Chapter: 3
Q61:
How can a linked list be traversed in the given code?
A. Using a for loop
B. Using a while loop
C. By calling the next() method repeatedly
D. By calling the add() method repeatedly
Correct Answer:
C
Chapter: 3
Q62:
What happens if currentNode is NULL in the next() method?
A. It throws an exception
B. It returns false
C. It moves to the head node
D. It moves to the last node
Correct Answer:
B
Chapter: 4
Q63:
What does the start() method in the linked list do?
A. Assigns NULL to headNode
B. Positions currentNode at start
C. Adds a new node at the start
D. Deletes the first node
Correct Answer:
B
Chapter: 4
Q64:
Which pointer in a linked list cannot move behind headNode in a singly-linked list?
A. lastCurrentNode
B. currentNode
C. Both lastCurrentNode and currentNode
D. None of the above
Correct Answer:
C
Chapter: 4
Q65:
What does the remove() method in a linked list do?
A. Removes the last node
B. Removes the node at the start
C. Removes the node pointed by currentNode
D. Removes the node pointed by headNode
Correct Answer:
C
Chapter: 4
Q66:
In the remove() method, what happens after executing delete currentNode;?
A. Node is added to the list
B. Memory is released to the system
C. Node is set to NULL
D. Nothing happens
Correct Answer:
B
Chapter: 4
Q67:
What is the return type of the length() method in the linked list?
A. void
B. int
C. Node*
D. bool
Correct Answer:
B
Chapter: 4
Q68:
What is the purpose of the lastCurrentNode->setNext(currentNode->getNext()) statement?
A. Connects currentNode to lastCurrentNode
B. Deletes currentNode
C. Bypasses the node pointed by currentNode
D. Initializes currentNode
Correct Answer:
C
Chapter: 4
Q69:
Which of the following operations is a one-step operation in a linked list?
A. Add
B. Remove
C. Find
D. Back
Correct Answer:
A
Chapter: 4
Q70:
What is the worst-case scenario in the find method in a linked list?
A. Finding x at the start
B. Finding x at the end
C. Not finding x in the list
D. Finding x in the middle
Correct Answer:
C
Chapter: 4
Q71:
How does the back method in a singly-linked list work?
A. Moves currentNode one step forward
B. Moves currentNode to headNode
C. Traverses the list from the start to find the previous node
D. Deletes the last node
Correct Answer:
C
Chapter: 4
Q72:
What additional pointer is used in a doubly-linked list that is not present in a singly-linked list?
A. currentNode
B. lastCurrentNode
C. prevNode
D. nextNode
Correct Answer:
C
Chapter: 4
Q73:
In a doubly-linked list, what does the getPrev() method do?
A. Sets the previous node
B. Returns the previous node's address
C. Sets the next node
D. Returns the next node's address
Correct Answer:
B
Chapter: 4
Q74:
What does the circularly-linked list avoid by linking the last node to the first node?
A. NULL pointers
B. Memory allocation
C. Node deletion
D. Backward traversal errors
Correct Answer:
A
Chapter: 4
Q75:
In a circularly-linked list, where does the next pointer of the last node point?
A. To the first node
B. To NULL
C. To the previous node
D. To the head node
Correct Answer:
A
Chapter: 4
Q76:
What kind of data structure is a circularly-linked list?
A. Non-linear
B. Linear
C. Tree
D. Graph
Correct Answer:
B
Chapter: 4
Q77:
Which method is typically used to move the currentNode to the start of the list?
A. back()
B. length()
C. start()
D. remove()
Correct Answer:
C
Chapter: 4
Q78:
What is the benefit of a doubly-linked list over a singly-linked list?
A. Easier backward traversal
B. More memory efficient
C. Simplified addition operation
D. Easier node removal
Correct Answer:
A
Chapter: 4
Q79:
How many pointers are there in a node of a doubly-linked list?
A. 1
B. 2
C. 3
D. 4
Correct Answer:
C
Chapter: 4
Q80:
Which operation in a linked list may require traversing the entire list?
A. Add
B. Remove
C. Find
D. Start
Correct Answer:
C