Linked Lists: A Comprehensive Guide for Graduate Students

Question 1

Among the following operations, which one exhibits a time complexity of O(1) when performed on linked lists?

Accepted Answer

Inserting an element at the start of the list

Answer

Removing an element situated in the middle of the list

Answer

Searching for a specific element within the list

Answer

Reversing the sequence of elements in the list

Question 2

When compared to arrays, a potential drawback of utilizing a linked list is that it:

Accepted Answer

Consumes more memory space

Answer

Can be traversed more efficiently

Answer

Can be easily resized

Answer

Is more appropriate for storing extensive datasets

Question 3

Which operation inserts a new node at the start of a singly linked list?

Accepted Answer

Push front

Answer

Insert after

Answer

Push back

Answer

Delete

Question 4

What is the time complexity of searching a value within a singly linked list?

Accepted Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Answer

O(1)

Question 5

What is the key difference between a singly linked list and a doubly linked list?

Accepted Answer

Doubly linked lists have pointers to both the previous and next nodes.

Answer

Singly linked lists can only be traversed forward.

Answer

Doubly linked lists are always circular.

Question 6

Define a circular linked list.

Accepted Answer

A linked list where the last node points to the first node, forming a circular structure.

Answer

A linked list used exclusively for implementing queues.

Answer

A linked list that can only be traversed in one direction.

Question 7

What is the name given to a stack implemented using a linked list data structure?

Accepted Answer

Linked list stack

Answer

Array stack

Answer

Queue

Question 8

Which of the following is a fundamental operation in a singly linked list?

Accepted Answer

Deleting a node

Answer

Reversing the entire list by altering the original node references

Answer

Appending an array

Answer

Modifying the head node without traversal

Question 9

What is the time complexity of traversing a singly linked list containing 'n' elements?

Accepted Answer

O(n)

Answer

O(n^2)

Answer

O(log n)

Answer

O(1)

Question 10

Which of the following data structures is most appropriate for representing a family tree?

Accepted Answer

Linked List

Answer

Stack

Answer

Queue

Answer

Array

Question 11

In a singly linked list, what is the primary purpose of the head node?

Accepted Answer

To point to the first node in the list

Answer

To provide direct access to any node in the list

Answer

To signify the end of the list

Answer

To store additional information about the list

Question 12

Which of the following methods modifies the original linked list?

Accepted Answer

Insert after

Answer

Length

Answer

Get

Answer

Copy

Question 13

Define a circular linked list.

Accepted Answer

A linked list where the last node points to the first

Answer

A linked list with no tail node

Answer

A linked list that can be traversed in one direction only

Question 14

What is the most efficient method for searching for a specific value within a singly linked list?

Accepted Answer

Linear traversal

Answer

Hashing

Answer

Indexed search

Answer

Binary search

Question 15

Which of the following operations can be performed more efficiently in a linked list compared to an array?

Accepted Answer

Insertion or deletion at any position

Answer

Sorting the elements

Answer

Accessing an element by its index

Answer

Searching for a specific element in a sorted list

Question 16

What is the time complexity of inserting an element at the beginning of a singly linked list?

Accepted Answer

O(1)

Answer

O(n^2)

Answer

O(log n)

Answer

O(n)

Question 17

Which of the following traversal methods visits all the nodes of a linked list in reverse order?

Accepted Answer

Recursive traversal from the last node

Answer

Tail recursion

Answer

Breadth-first search

Answer

Iterative traversal from the first node

Question 18

What is the primary purpose of a head node in a linked list?

Accepted Answer

To point to the first node of the list and keep track of the list's size

Answer

To store the size of the list

Answer

To mark the end of the list

Answer

To provide access to all other nodes in the list

Question 19

What is the key difference between a singly linked list and a doubly linked list?

Accepted Answer

A doubly linked list has both forward and backward pointers, while a singly linked list only has forward pointers

Answer

A doubly linked list is more efficient than a singly linked list

Question 20

Which algorithm is commonly used to reverse a linked list?

Accepted Answer

Iterative reversal

Answer

Divide-and-conquer

Answer

Greedy algorithm

Answer

Dynamic programming

Question 21

Which of the following data structures can be used to represent a graph efficiently?

Accepted Answer

Adjacency list using linked lists

Answer

Binary tree

Answer

Queue

Answer

Hash table

Question 22

What is a key advantage of using a linked list over an array for data storage?

Accepted Answer

Linked lists allow for dynamic memory allocation, enabling them to adapt to changing data size requirements.

Answer

Linked lists necessitate less memory than arrays.

Answer

Linked lists are more efficient for accessing elements at specific positions.

Question 23

In a singly linked list, what does the 'next' field of the last node typically point to?

Accepted Answer

NULL

Answer

The first node in the list

Answer

A random node within the list

Question 24

Consider a linked list comprising nodes A, B, and C. To insert a new node 'D' after node 'B', which steps are necessary?

Accepted Answer

1. Assign the 'next' field of node 'D' to point to node 'C'. 2. Assign the 'next' field of node 'B' to point to node 'D'.

Answer

1. Assign the 'next' field of node 'D' to point to node 'A'. 2. Assign the 'next' field of node 'B' to point to node 'D'.

Answer

1. Assign the 'next' field of node 'D' to point to node 'B'. 2. Assign the 'next' field of node 'C' to point to node 'D'.

Question 25

What is the time complexity for searching for a specific element within a singly linked list?

Accepted Answer

O(n)

Answer

O(n^2)

Answer

O(1)

Answer

O(log n)

Question 26

Which advantage does a doubly linked list offer over a singly linked list?

Accepted Answer

Doubly linked lists permit efficient traversal in both forward and backward directions.

Answer

Reduced memory consumption

Answer

Faster insertion and deletion operations at the beginning of the list

Question 27

In a circular linked list, the 'next' field of the last node typically points to:

Accepted Answer

The first node in the list

Answer

A random node within the list

Answer

NULL

Answer

The previous node

Question 28

Which scenario is best suited for utilizing a linked list?

Accepted Answer

Managing a dynamic queue where elements are added and removed from different ends.

Answer

Performing rapid binary search operations on a sorted dataset

Answer

Storing a fixed-size collection of data where efficient indexing is crucial

Question 29

When removing a node from a linked list, which step is critical to ensure the integrity of the list?

Accepted Answer

Updating the 'next' field of the preceding node to point to the node succeeding the deleted node

Answer

Setting the deleted node's 'next' field to NULL

Answer

Deleting the node's data field

Question 30

Which statement about linked lists is accurate?

Accepted Answer

Linked lists can be implemented using dynamic memory allocation

Answer

Linked lists are inherently faster than arrays for all operations

Answer

Linked lists always require more memory than arrays.

Question 31

Which is NOT an advantage of linked lists over arrays?

Accepted Answer

Fixed size and memory allocation

Answer

Flexibility in data storage

Answer

Dynamic memory allocation

Answer

Efficient insertion and deletion at any position

Question 32

In a singly linked list, each node consists of a data field and a:

Accepted Answer

Reference to the subsequent node.

Answer

Reference to the preceding node.

Answer

Reference to the final node.

Answer

Reference to the initial node.

Question 33

What is the time complexity for inserting a node at the start of a singly linked list?

Accepted Answer

O(1)

Answer

O(n^2)

Answer

O(log n)

Answer

O(n)

Question 34

Which data structure can be efficiently implemented using a linked list?

Accepted Answer

Stack

Answer

Hash Table

Answer

Binary Search Tree

Answer

Heap

Question 35

A circular linked list is characterized by:

Accepted Answer

The final node referencing the initial node.

Answer

All nodes referencing the same node.

Answer

The initial node referencing the final node.

Answer

All nodes referencing the initial node.

Question 36

What is the purpose of a sentinel node in a linked list?

Accepted Answer

To simplify handling exceptional cases like an empty list or insertion at the beginning.

Answer

To provide a starting point for sorting the list.

Answer

To store the list's size.

Question 37

A doubly linked list differs from a singly linked list by having:

Accepted Answer

References to both the previous and next nodes.

Answer

No references at all.

Answer

References only to the initial node.

Answer

References only to the final node.

Question 38

In which scenario would a linked list be more suitable than an array?

Accepted Answer

Implementing a dynamic queue where elements need to be enqueued and dequeued efficiently.

Answer

Implementing a hash table with a predefined size for rapid key-value lookup.

Answer

Storing a fixed-size list of student records with frequent random access.

Question 39

Which of the following is a fundamental operation performed on a linked list?

Accepted Answer

Insertion

Answer

Hashing

Answer

Sorting

Answer

Recursion

Question 40

What is the time complexity, in Big O notation, to search for an element in a singly linked list of 'n' elements?

Accepted Answer

O(n)

Answer

O(n^2)

Answer

O(1)

Answer

O(log n)

Question 41

Which data structure is NOT typically considered a variation of a linked list?

Accepted Answer

Binary Tree

Answer

Queue

Answer

Circular Linked List

Answer

Doubly Linked List

Question 42

What is a primary advantage of choosing a linked list over an array for data storage?

Accepted Answer

Dynamic memory allocation, allowing for efficient insertion and deletion

Answer

Direct access to elements using their index

Answer

Improved data locality, leading to better cache performance

Answer

Faster search times for unsorted data

Question 43

Given a linked list with head node 'head' and a new node with value 'x', which code snippet correctly appends the new node to the end of the list?

Accepted Answer

Node* temp = head; while(temp->next != NULL) temp = temp->next; temp->next = new Node(x);

Answer

Node* temp = new Node(x); temp->next = head; head = temp;

Answer

Node* new_node = new Node(x); new_node->next = head; head = new_node;

Answer

head->next = new Node(x);

Question 44

What is the primary function of a sentinel node in a linked list?

Accepted Answer

To simplify edge case handling during insertion and deletion, particularly at the beginning or end

Answer

To improve memory efficiency by reducing the number of nodes

Answer

To store metadata about the linked list, such as the number of nodes

Answer

To enhance search performance by providing a shortcut to the middle of the list

Question 45

What is a potential drawback of using a linked list compared to an array?

Accepted Answer

Increased memory usage due to the storage of node pointers

Answer

Inability to handle dynamic resizing

Answer

Inefficient traversal, making it slow to iterate through all elements

Answer

Poor cache locality, resulting in slower memory access

Question 46

Given a linked list with head node 'head', which code snippet correctly removes the first node with value 'x'?

Accepted Answer

Node* temp = head, *prev = NULL; while (temp != NULL && temp->value != x) { prev = temp; temp = temp->next; } if (temp != NULL) { if (prev != NULL) prev->next = temp->next; else head = temp->next; delete temp; }

Answer

Node* temp = head; while(temp->value != x) temp = temp->next; delete temp;

Answer

delete head;

Answer

free(head);

Question 47

What is the time complexity, expressed in Big O notation, to delete a node from the middle of a singly linked list containing 'n' elements?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(n^2)

Answer

O(log n)

Question 48

You have two sorted linked lists, L1 and L2. Which algorithm is typically used to efficiently combine them into a single sorted linked list?

Accepted Answer

Merge Sort

Answer

Bubble Sort

Answer

Quick Sort

Answer

Heap Sort