Master Basic Data Structures: Arrays, Linked Lists, Stacks, and Queues

Question 1

Which data structure maintains a first-in, first-out (FIFO) ordering, meaning the first element added will be the first removed?

Accepted Answer

Queue

Answer

Stack

Answer

Linked List

Answer

Tree

Question 2

Which of the following is NOT an advantage of using an array over a singly linked list?

Accepted Answer

Easier insertion and deletion in the middle

Answer

Faster random access

Answer

More efficient memory usage

Answer

Better cache locality

Question 3

What is the time complexity of searching for an element in an unsorted array?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n^2)

Question 4

Which data structure uses a Last-In, First-Out (LIFO) approach, where the last element added is the first removed?

Accepted Answer

Stack

Answer

Queue

Answer

Linked List

Answer

Heap

Question 5

Which of the following sorting algorithms generally has the best average-case time complexity?

Accepted Answer

Merge Sort

Answer

Bubble Sort

Answer

Selection Sort

Answer

Quick Sort

Question 6

What is the primary purpose of using a hash function in a hash table?

Accepted Answer

To map keys to unique indices in the hash table

Answer

To ensure that all keys are evenly distributed across the hash table

Answer

To reduce the size of the hash table

Answer

To store the values associated with keys

Question 7

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

Accepted Answer

Circular linked lists have a tail node that points to the head node, while doubly linked lists do not.

Answer

Doubly linked lists have a tail node that points to the head node, while circular linked lists do not.

Answer

Circular linked lists can only be traversed in one direction, while doubly linked lists can be traversed in both directions.

Answer

Doubly linked lists can only be traversed in one direction, while circular linked lists can be traversed in both directions.

Question 8

When selecting the most appropriate data structure for a specific task, which of the following factors should be considered?

Accepted Answer

Type of data

Accepted Answer

Size of the data collection

Accepted Answer

Expected data access patterns

Answer

Ease of implementation

Question 9

Which data structure allows elements to be inserted and deleted at any position efficiently?

Accepted Answer

Linked List

Answer

Array

Answer

Stack

Answer

Queue

Question 10

What is the time complexity of a successful search for an element in a balanced binary search tree?

Accepted Answer

O(log n)

Answer

O(1)

Answer

O(n)

Answer

O(n^2)

Question 11

Which operation is NOT fundamental to a stack data structure?

Accepted Answer

Insert

Answer

Push

Answer

Pop

Answer

Peek

Question 12

What is the primary advantage of using a doubly linked list over a singly linked list?

Accepted Answer

Ability to traverse in both directions

Answer

Faster insertion and deletion

Answer

Improved memory efficiency

Answer

Enhanced search performance

Question 13

What is the time complexity of inserting an element into a hash table using linear probing?

Accepted Answer

O(1) on average

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 14

Which data structure is most appropriate for representing hierarchical relationships?

Accepted Answer

Tree

Answer

Array

Answer

Linked List

Answer

Graph

Question 15

What is the key difference between a breadth-first search (BFS) and a depth-first search (DFS)?

Accepted Answer

BFS explores all nodes at each level before moving to the next level, while DFS explores as far as possible along each branch before backtracking.

Answer

Both algorithms have the same time complexity.

Answer

BFS uses a stack, while DFS uses a queue.

Answer

DFS explores all nodes at each level before moving to the next level, while BFS explores as far as possible along each branch before backtracking.

Question 16

Which sorting algorithm typically has the best average-case time complexity?

Accepted Answer

Merge Sort

Answer

Insertion Sort

Answer

Quick Sort

Answer

Heap Sort

Question 17

What is the primary purpose of a binary search tree?

Accepted Answer

To store data in a sorted order and perform efficient searches

Answer

To implement a priority queue

Answer

To represent hierarchical relationships

Answer

To store data in a hash table

Question 18

Which data structure adheres to the Last-In-First-Out (LIFO) principle?

Accepted Answer

Stack

Answer

Array

Answer

Linked list

Answer

Queue

Question 19

What is the time complexity of the enqueue operation in a queue?

Accepted Answer

O(1)

Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Question 20

Which data structure is optimal for storing a large number of elements that need to be processed in a specific order?

Accepted Answer

Queue

Answer

Array

Answer

Linked list

Answer

Stack

Question 21

How does a singly linked list differ from a doubly linked list?

Accepted Answer

A singly linked list has nodes linked forward, while a doubly linked list has nodes linked forward and backward

Answer

A singly linked list is faster than a doubly linked list

Answer

A doubly linked list can insert and delete elements more efficiently

Answer

There is no difference

Question 22

Which data structure is employed to implement a priority queue?

Accepted Answer

Binary heap

Answer

Array

Answer

Linked list

Answer

Stack

Question 23

What is the space complexity of storing an array of n integers?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n^2)

Question 24

Define a hash function.

Accepted Answer

A function that maps a data item to a unique identifier

Answer

A function that compresses data to save space

Answer

A function that encrypts data for security

Answer

A function that generates random numbers

Question 25

What is the time complexity of an inorder traversal in a binary search tree?

Accepted Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Question 26

What is the primary operation performed on a linked list?

Accepted Answer

Traversing

Answer

Sorting

Question 27

Which data structure is most suitable for implementing the Last In First Out (LIFO) principle?

Accepted Answer

Stack

Answer

Array

Answer

Linked List

Answer

Queue

Question 28

Which data structure is used to store a collection of unique elements, excluding duplicates?

Accepted Answer

Set

Answer

List

Answer

Dictionary

Answer

Array

Question 29

What is the time complexity of inserting an element into a hash table?

Accepted Answer

O(1)

Answer

O(n)

Answer

O(log n)

Answer

O(n^2)

Question 30

When inserting an element at a specific position (not the beginning or end) in a singly linked list with n elements, what is the time complexity?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n^2)

Question 31

Which operation is not supported by an array?

Accepted Answer

Reverse

Answer

Insert

Answer

Delete

Answer

Search

Question 32

A linked list consists of:

Accepted Answer

Nodes connected by pointers

Answer

A block of memory

Answer

Objects in a hierarchy

Answer

Key-value pairs

Question 33

What is the time complexity of accessing an element in an array?

Accepted Answer

O(1)

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 34

Which disadvantage is associated with a stack?

Accepted Answer

Limited access to elements

Answer

High memory usage

Answer

Slow searching

Answer

First-in, first-out behavior

Question 35

What is the purpose of a queue?

Accepted Answer

Storing data in FIFO order

Answer

Providing random access to elements

Answer

Supporting efficient searching

Answer

Handling multiple threads

Question 36

What is the fundamental difference between a stack and a queue?

Accepted Answer

Stacks follow LIFO, queues follow FIFO

Answer

Queues follow LIFO, stacks follow FIFO

Answer

Stacks have limited access, queues have unlimited access

Answer

Queues have limited access, stacks have unlimited access

Question 37

Which algorithm is used to search for an element in a sorted array?

Accepted Answer

Binary search

Answer

Linear search

Answer

Breadth-first search

Answer

Depth-first search

Question 38

What is the time complexity of inserting an element into a linked list at the head?

Accepted Answer

O(1)

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 39

Which data structure is used to implement the Breadth-First Search (BFS) algorithm?

Accepted Answer

Queue

Answer

Tree

Answer

Stack

Answer

LinkedList

Question 40

Which of the following is NOT an advantage of using an array over a linked list?

Accepted Answer

Faster insertion and deletion

Answer

Less memory overhead

Answer

Faster access to random elements

Answer

Cache friendly

Question 41

What is the time complexity of finding an element in a singly linked list?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(n^2)

Answer

O(log n)

Question 42

Which data structure is most appropriate for storing a collection of unique elements?

Accepted Answer

Set

Answer

List

Answer

Map

Question 43

What is the purpose of a hash function in the context of data structures?

Accepted Answer

To map a key to a unique index in a hash table

Answer

To sort a collection of elements

Answer

To search for an element in a binary tree

Question 44

What is the key difference between a balanced binary tree and an unbalanced binary tree?

Accepted Answer

The height of the left and right subtrees differs by at most 1 in a balanced binary tree.

Answer

A balanced binary tree has more leaves than an unbalanced binary tree.

Answer

An unbalanced binary tree can never be a complete binary tree.

Question 45

What is the primary advantage of using a skip list?

Accepted Answer

Efficient search and update operations in sorted data

Answer

Implementing a priority queue

Answer

Storing large amounts of data that cannot fit in memory

Question 46

Which data structure allows elements to be added and removed from both ends, but accessing elements in the middle is inefficient?

Accepted Answer

Deque

Answer

Stack

Answer

Queue

Answer

Array

Question 47

What is the main advantage of using a linked list over an array for storing data?

Accepted Answer

Dynamic memory allocation and efficient insertion/deletion in the middle.

Answer

Faster access to elements by index.

Answer

Fixed size and better memory utilization.

Question 48

In a queue, which operation adds an element to the back?

Accepted Answer

Enqueue

Answer

Pop

Answer

Dequeue

Answer

Push

Question 49

If you have an array of size 10, how are its elements stored in memory?

Accepted Answer

All elements are stored in consecutive memory locations.

Answer

Memory is dynamically allocated for each element.

Answer

Elements are scattered throughout memory.

Question 50

Which data structure is commonly used to implement a function call stack?

Accepted Answer

Stack

Answer

Linked List

Answer

Tree

Answer

Queue

Question 51

In a linked list, what is the purpose of the 'next' pointer within each node?

Accepted Answer

It points to the next node in the list.

Answer

It indicates the start of the list.

Answer

It stores the value of the current node.

Question 52

A program needs to efficiently manage a collection of elements where adding and removing elements is frequent, but random access is less important. Which data structure would be suitable?

Accepted Answer

Linked List

Answer

Array

Answer

Stack

Question 53

Which data structure is typically used to manage a task queue in an operating system?

Accepted Answer

Queue

Answer

Tree

Answer

Graph

Answer

Stack

Question 54

What is the key difference between a stack and a queue?

Accepted Answer

A stack uses a LIFO (Last-In, First-Out) order, while a queue uses a FIFO (First-In, First-Out) order.

Answer

A stack allows random access, while a queue does not.