Data Structures Learning Quizzes for Computer Science Students

Question 1

What is the time complexity of finding an element in an unsorted array of size n?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n^2)

Question 2

Which of the following is NOT an advantage of utilizing linked lists in programming?

Accepted Answer

Constant-time access to any element

Answer

Dynamic memory management

Answer

Efficient insertion and removal of elements

Answer

Reduced memory overhead

Question 3

When faced with a collection of distinct elements, which data structure is most appropriate for efficient storage and retrieval?

Accepted Answer

Hash table

Answer

Array

Answer

Linked list

Answer

Binary search tree

Question 4

What is the time complexity of inserting a new node into a balanced binary search tree?

Accepted Answer

O(log n)

Answer

O(1)

Answer

O(n)

Answer

O(n^2)

Question 5

What is the process of transforming a binary tree into a linear data structure known as?

Accepted Answer

Tree flattening

Answer

Tree traversal

Answer

Tree hashing

Answer

Tree compression

Question 6

Which of the following is **not** an advantage of using arrays?

Accepted Answer

Dynamic memory allocation

Answer

Efficient indexing

Answer

Random access

Answer

Cache-friendly memory access

Question 7

What is the average time complexity for searching an element in a linked list?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n^2)

Question 8

Which data structure is most appropriate for implementing a 'last in, first out' behaviour?

Accepted Answer

Stack

Answer

Array

Answer

Queue

Answer

Tree

Question 9

What is the key difference between a circular queue and a regular queue?

Accepted Answer

Circular queues allow for wraparound access, while regular queues do not.

Answer

Circular queues have a fixed size, while regular queues do not.

Answer

Circular queues are more efficient for enqueue and dequeue operations.

Answer

There is no difference between circular queues and regular queues.

Question 10

Which of the following operations is **not** supported by a binary search tree?

Accepted Answer

Sorting

Answer

Insertion

Answer

Deletion

Answer

Searching

Question 11

Which of the following is **not** an advantage of using a graph data structure?

Accepted Answer

Searching for elements in a sorted order

Answer

Representing complex relationships between objects

Answer

Efficiently finding the shortest path between two nodes

Answer

Storing large amounts of data in a structured manner

Question 12

What is the worst-case time complexity of Dijkstra's algorithm for finding the shortest path in a graph?

Accepted Answer

O(E log V)

Answer

O(V)

Answer

O(V^2)

Answer

O(V log V)

Question 13

Which of the following actions is not supported by a queue data structure?

Accepted Answer

Randomly accessing an element

Answer

Enqueue (adding an element)

Answer

Dequeue (removing an element)

Answer

Peek (viewing the front element)

Question 14

For an array of size 'n', what is the time complexity of searching for a specific element?

Accepted Answer

O(n)

Answer

O(1)

Answer

O(log n)

Answer

O(n^2)

Question 15

Which data structure is primarily designed for storing pairs of data, where each pair consists of a unique key and an associated value?

Accepted Answer

Hash table

Answer

Array

Answer

Linked list

Answer

Stack

Question 16

In a linked list, what is the function of a tail pointer?

Accepted Answer

It points to the last node in the list

Answer

It points to the first node in the list

Answer

It stores the number of nodes in the list

Answer

It connects the list to another linked list

Question 17

What is the time complexity of adding an element to the beginning of a linked list of size 'n'?

Accepted Answer

O(1)

Answer

O(log n)

Answer

O(n)

Answer

O(n^2)

Question 18

For implementing a browser's history feature, which data structure is most suitable?

Accepted Answer

Stack

Answer

Array

Answer

Linked list

Answer

Queue

Question 19

How do you access the first element of an array in Java?

Accepted Answer

myArray[0]

Answer

myArray[1]

Answer

myArray.get(0)

Answer

myArray.first()

Question 20

What is the correct way to create a linked list in Java?

Accepted Answer

LinkedList myLinkedList = new LinkedList<>();

Answer

LinkedList myLinkedList = new LinkedList<String>();

Answer

LinkedList<String> myLinkedList = LinkedList();

Answer

LinkedList myLinkedList = LinkedList<String>();

Question 21

How do you remove the first element from a linked list in Java?

Accepted Answer

myLinkedList.removeFirst();

Answer

myLinkedList.removeLast();

Answer

myLinkedList.remove(element);

Answer

myLinkedList.pop();

Question 22

What is the correct way to create a stack in Java?

Accepted Answer

Stack myStack = new Stack<>();

Answer

Stack myStack = new Stack<String>();

Answer

Stack<String> myStack = Stack();

Answer

Stack myStack = Stack<String>();

Question 23

How do you push an element onto a stack in Java?

Accepted Answer

myStack.push(element);

Answer

myStack.add(element);

Answer

myStack.addLast(element);

Answer

myStack.insert(element);

Question 24

How do you pop an element from a stack in Java?

Accepted Answer

myStack.pop();

Answer

myStack.removeFirst();

Answer

myStack.removeLast();

Answer

myStack.delete();

Question 25

What is the primary operation performed by a Last-In-First-Out (LIFO) data structure?

Accepted Answer

Insertion and deletion from the end

Answer

Insertion and deletion from the front

Answer

Insertion and deletion from the middle

Answer

Searching for a specific element

Question 26

What is a circular buffer?

Accepted Answer

A buffer that wraps around to the beginning after reaching the end

Answer

A buffer that stores data in a circular fashion

Answer

A buffer that is used to store temporary data

Answer

A buffer that is protected from buffer overflow

Question 27

Which is a disadvantage of using a binary search tree (BST)?

Accepted Answer

Can be unbalanced, affecting performance

Answer

Difficult to implement and maintain

Answer

Not suitable for storing large amounts of data

Answer

Does not support efficient insertion and deletion

Question 28

How does a hash table differ from a binary search tree?

Accepted Answer

Hash tables use a key to directly access elements, while BSTs use a sorted order

Answer

BSTs use a key to directly access elements, while hash tables use a sorted order

Answer

Hash tables are more efficient for searching, while BSTs are more efficient for insertion and deletion

Answer

BSTs are more efficient for searching, while hash tables are more efficient for insertion and deletion

Question 29

What is the time complexity of searching 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 30

What is the average time complexity of searching an element in a linked list?

Accepted Answer

O(N)

Answer

O(N log N)

Answer

O(1)

Answer

O(log N)

Question 31

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

Accepted Answer

Queues follow FIFO (First-In-First-Out), while stacks follow LIFO (Last-In-First-Out).

Answer

There is no fundamental difference between a queue and a stack.

Answer

Queues are used for processing data, while stacks are used for storing data

Answer

Queues store elements in arrays, while stacks store elements in linked lists

Question 32

Which of the following is a characteristic of a binary search tree (BST)?

Accepted Answer

The left subtree of a node contains only values smaller than the node, and the right subtree contains only values larger than the node.

Answer

All nodes in the tree have exactly two children.

Answer

The root node is always the smallest value in the tree.

Answer

The tree is always perfectly balanced.

Question 33

What is the average time complexity of finding a node in a balanced binary search tree?

Accepted Answer

O(log N)

Answer

O(N)

Answer

O(N log N)

Answer

O(1)

Question 34

Which of the following is a disadvantage of hash tables?

Accepted Answer

Collisions can occur, leading to decreased performance

Answer

Easy to implement

Answer

Fast lookup and insertion

Answer

Efficient use of memory