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Data Structures for Coding Interviews in JavaScript

The ultimate guide to data structures for coding interviews in JavaScript. Developed by FAANG engineers to help you write better code and ace industry benchmarks.

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Data structures are amongst the very fundamentals of Computer Science and are often a core decision in developing efficient programs. Consequently, they are also largely categorized as a vital benchmark of computer science knowledge when it comes to industry interviews. This course contains a detailed review of all the common data structures and provides implementation level details in JavaScript to allow readers to become well equipped with all the different data structures they can leverage to write better code!

Data structures are amongst the very fundamentals of Computer Science and are often a core decision in developing efficient prog...Show More

Content

227 Lessons24 Quizzes65 Challenges

Introduction to Complexity Measures

22 Lessons

Learn how to use complexity measures to compare and analyze algorithm efficiency effectively.

Comparing Algorithms

Example: Measuring Time Complexity of a Single Loop Algorithm

Example: Time Complexity of an Algorithm With Nested Loops

Introduction to Asymptotic Analysis and Big O

Other Common Asymptotic Notations and Why Big O Trumps Them

Useful Formulae

Common Complexity Scenarios

Challenge: Big (O) of Nested Loop With Addition

Solution: Big (O) of Nested Loop With Addition

Challenge: Big (O) of Nested Loop With Subtraction

Solution: Big (O) of Nested Loop With Subtraction

Challenge: Big (O) of Nested Loop With Multiplication

Solution: Big (O) of Nested Loop With Multiplication

Challenge: Nested Loop With Multiplication (Basic)

Solution: Nested Loop With Multiplication (Basic)

Challenge: Nested Loop With Multiplication (Intermediate)

Solution: Nested Loop With Multiplication (Intermediate)

Challenge: Nested Loop With Multiplication (Advanced)

Solution: Nested Loop With Multiplication (Advanced)

Challenge: Nested Loop With Multiplication (Pro)

Solution: Nested Loop With Multiplication (Pro)

Quiz: Test Your Understanding of Complexity

Introduction to Arrays

25 Lessons

Unpack the core of array manipulation techniques, variable declaration differences, and coding challenges.

Arrays

The var vs. let vs. const

Challenge: Remove Even Integers From Array

Solution: Remove Even Integers From Array

Challenge: Merge Two Sorted Arrays

Solution: Merge Two Sorted Arrays

Challenge: Find Two Numbers That Add Up to K

Solution: Find Two Numbers That Add Up to K

Challenge: Product of Array Except Self

Solution: Product of Array Except Self

Challenge: Find Minimum Value in Array

Solution: Find Minimum Value in Array

Challenge: First Non-Repeating Integer in an Array

Solution: First Non-Repeating Integer in an Array

Challenge: Find Second Maximum Value in an Array

Solution: Find Second Maximum Value in an Array

Challenge: Rotate Array

Solution: Rotate Array

Challenge: Rearrange Positive & Negative Values

Solution: Rearrange Positive & Negative Values

Challenge: Rearrange Sorted Array in Max/Min Form

Solution: Rearrange Sorted Array in Max/Min Form

Challenge: Maximum Subarray

Solution: Maximum Subarray

Arrays Quiz: Test Your Understanding of Arrays

Introduction to Linked Lists

31 Lessons

Work your way through the basics, operations, and comparisons of singly and doubly linked lists.

Singly Linked Lists (SLL)

Basic Linked List Operations

Singly Linked List Insertion

Singly Linked List Deletion

Deletion at the Tail

Linked Lists vs. Arrays

Doubly Linked Lists (DLL)

Singly Linked Lists vs. Doubly Linked Lists

Challenge: Insertion at Tail

Solution: Insertion at Tail

Challenge: Search in a Singly Linked List

Solution: Search in a Singly Linked List

Challenge: Deletion by Value

Solution: Deletion by Value

Challenge: Find the Length of a Linked List

Solution: Find the Length of a Linked List

Challenge: Reverse Linked List

Solution: Reverse Linked List

Challenge: Linked List Cycle

Solution: Linked List Cycle

Challenge: Middle of the Linked List

Solution: Middle of the Linked List

Challenge: Remove Duplicates from a Linked List

Solution: Remove Duplicates from a Linked List

Challenge: Union and Intersection of Linked Lists

Solution: Union and Intersection of Linked Lists

Challenge: Return the Nth Node from End

Solution: Return the Nth Node from End

Challenge: Find If a Doubly Linked List Is a Palindrome

Solution: Find If a Doubly Linked List Is a Palindrome

Linked Lists Quiz: Test Your Understanding of Linked Lists

Introduction to Stack/Queues

25 Lessons

Grasp the fundamentals of stack and queue operations, implementations, and practical challenges.

What is a Stack?

Stack (Implementation)

What is a Queue?

Queue (Implementation)

Challenge: Generate Binary Numbers From 1 to n Using a Queue

Solution: Generate Binary Numbers From 1 to n Using a Queue

Challenge: Implement Two Stacks Using One Array

Solution: Implement Two Stacks Using One Array

Challenge: Reverse First k Elements of Queue

Solution: Reverse First k Elements of Queue

Challenge: Implement Queue Using Stacks

Solution: Implement Queue Using Stacks

Challenge: Sort Values in a Stack

Solution: Sort Values in a Stack

Challenge: Evaluate Postfix Expression Using a Stack

Solution: Evaluate Postfix Expression Using a Stack

Challenge: Next Greater Element Using a Stack

Solution: Next Greater Element Using a Stack

Challenge: Find the Celebrity

Solution: Find the Celebrity

Challenge: Valid Parentheses

Solution: Valid Parentheses

Challenge: Min Stack

Solution: Min Stack

Stack/Queue Quiz: Test Your Understanding of Stack/Queue

Introduction to Graphs

26 Lessons

Dig deeper into the fundamentals, implementation, and challenges of graphs and their applications.

What is a Graph?

Types of Graphs

Representation of Graphs

Graph Implementation

Complexities of Graph Operations

What is a Bipartite Graph?

Graph Traversal Algorithms

Challenge: Implement Breadth-First Search

Solution: Implement Breadth-First Search

Challenge: Implement Depth-First Search

Solution: Implement Depth-First Search

Challenge: Detect Cycle in a Directed Graph

Solution: Detect Cycle in a Directed Graph

Challenge: Find a Mother Vertex in a Directed Graph

Solution: Find a Mother Vertex in a Directed Graph

Challenge: Count the Number of Edges in an Undirected Graph

Solution: Count the Number of Edges in an Undirected Graph

Challenge: Check If a Path Exists between Two Vertices

Solution: Check If a Path Exists between Two Vertices

Challenge: Graph Valid Tree

Solution: Graph Valid Tree

Challenge: Find the Shortest Path between Two Vertices

Solution: Find the Shortest Path between Two Vertices

Challenge: Remove Edge from a Directed Graph

Solution: Remove Edge from a Directed Graph

Graph Quiz: Test Your Understanding of Graphs

Introduction to Trees

38 Lessons

Investigate tree fundamentals, properties, and various types for coding interviews in JavaScript.

An Introduction to Trees and Basic Tree Properties!

What is a Binary Tree?

What Makes a Tree 'Balanced'?

More on Complete Binary Trees

Skewed Binary Tree

What is a Binary Search Tree (BST)?

Implementing a Binary Search Tree in JavaScript

Binary Search Tree Insertion

Binary Search Tree Insertion (Implementation)

Pre-Order Traversal

In-Order Traversal

Post-Order Traversal

Searching in a Binary Search Tree (Implementation)

Deletion in Binary Search Tree

Deletion in Binary Search Tree (Implementation)

What is an AVL Tree?

AVL Insertion

AVL Deletion

What is a Red-Black Tree?

Red-Black Tree Insertion

Red-Black Tree Deletion

What is a 2-3 Tree?

2-3 Insertion

2-3 Deletion (Element at Leaf)

2-3 Deletion (Element at Internal Node)

2-3-4 Trees

Overview of Trees

Challenge: Find Minimum Value in Binary Search Tree

Solution: Find Minimum Value in Binary Search Tree

Challenge: Find kth Maximum Value in Binary Search Tree

Solution: Find kth Maximum Value in Binary Search Tree

Challenge: Find Ancestors of a Given Node in a BST

Solution: Find Ancestors of a Given Node in a BST

Challenge: Find the Height of Binary Search Tree

Solution: Find the Height of Binary Search Tree

Challenge: Find Nodes at k Distance from the Root

Solution: Find Nodes at k Distance from the Root

Trees Quiz: Test Your Understanding of Trees

Trie

14 Lessons

Build on trie data structure for efficient string operations, including insertion, search, and deletion.

Challenge: Total Number of Words in a Trie

Solution: Total Number of Words in a Trie

Challenge: Find All Words Stored in Trie

Solution: Find All Words Stored in Trie

Challenge: Array Sort Using Trie

Solution: Array Sort Using Trie

Challenge: Word Formation From a Dictionary Using Trie

Solution: Word Formation From a Dictionary Using Trie

Trie Quiz: Test Your Understanding of Tries

Introduction to Heap

12 Lessons

Get familiar with heap data structures, their implementations, and solving related challenges.

What is a Heap?

Max Heap: Introduction

Max Heap (Implementation)

Min Heap: Introduction

Min Heap (Implementation)

Challenge: Convert Max Heap to Min Heap

Solution: Convert Max Heap to Min Heap

Challenge: Find k Smallest Elements in an Array

Solution: Find k Smallest Elements in an Array

Challenge: Find K Largest Elements in an Array

Solution: Find K Largest Elements in an Array

Heap Quiz: Test Your Understanding of Heaps

Introduction to Hashing

32 Lessons

Unpack the core of hashing concepts, collisions, and hash table implementation. Explore practical challenges using hash tables.

What is a Hash Table?

The Hash Function

Collisions in Hash Tables

Building a Hash Table from Scratch

Add/Remove & Search in Hash Table (Implementation)

A Quick Overview of Hash Tables

Trees vs Hash Tables

Challenge: An Array as a Subset of Another Array

Solution: An Array as a Subset of Another Array

Challenge: Check if Arrays are Disjoint

Solution: Check if Arrays are Disjoint

Challenge: Find Symmetric Pairs in an Array

Solution: Find Symmetric Pairs in an Array

Challenge: Trace the Complete Path of a Journey

Solution: Trace the Complete Path of a Journey

Challenge: Find Two Pairs in an Array Such That a+b = c+d

Solution: Find Two Pairs in an Array Such That a+b = c+d

Challenge: A Subarray with a Sum of 0

Solution: A Subarray with a Sum of 0

Challenge: Word Formation Using a Hash Table

Solution: Word Formation Using a Hash Table

Challenge: Find Two Numbers That Add up to k—Hashing

Solution: Find Two Numbers That Add up to k—Hashing

Challenge: First Non-Repeating Integer in an Array—Hashing

Solution: First Non-Repeating Integer in an Array—Hashing

Challenge: Linked List Cycle—Hashing

Solution: Linked List Cycle—Hashing

Challenge: Remove Duplicates from Linked List - Hashing

Solution: Remove Duplicates from Linked List - Hashing

Challenge: Union and Intersection of Linked Lists — Hashing

Solution: Union and Intersection of Linked Lists — Hashing

Hashing Quiz: Test Your Understanding of Hashing

10.

Summary of Data Structures

2 Lessons

Examine the differences and performance of linear vs. non-linear data structures.

Overview of Linear & Non-Linear Data Structures

Conclusion

Certificate of Completion

Showcase your accomplishment by sharing your certificate of completion.

Course Author:

Coderust

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Free Resources

Frequently Asked Questions

Which data structure is most asked in an interview?

Arrays and linked lists are the most commonly asked data structures in interviews because they form the foundation for many algorithmic problems. Additionally, hash tables (for fast lookups), stacks, queues, and binary trees (like binary search trees and heaps) are frequently discussed due to their importance in solving various practical problems. Mastery of these core data structures is crucial as they often serve as building blocks for more complex algorithms and solutions.

Can I use JavaScript for DSA interviews?

You can use JavaScript for data structures and algorithms (DSA) interviews. JavaScript is increasingly accepted, especially for front-end and full-stack developer roles, because it demonstrates versatility and familiarity with web technologies. The language offers built-in data structures like arrays, objects, sets, and maps, sufficient for solving most DSA problems. However, JavaScript lacks some lower-level control than languages like C++ or Java, so be prepared to clearly explain your solutions and handle any performance considerations.

Is DSA easy in JavaScript?

Yes, DSA can be relatively easy in JavaScript due to its simple syntax, dynamic typing, and built-in data structures like arrays, objects, sets, and maps. These features make it straightforward to implement common algorithms and manipulate data. However, JavaScript lacks advanced data structures and low-level control in other languages, which might require creative approaches for certain problems. Overall, JavaScript is user-friendly for learning and practicing DSA concepts.

How many data structures are in JavaScript?

JavaScript has several built-in data structures: primitive types like Number, String, and Boolean, and non-primitive types like Object, Array, Map, Set, WeakMap, and WeakSet. Each data structure serves different purposes, such as arrays for ordered lists, objects for key-value pairs, maps for efficient key-value storage, and sets for storing unique values. These structures are versatile enough to handle most data manipulation needs in JavaScript.

How to prepare DSA in 10 days

To prepare for DSA in 10 days, focus on the most important topics:

Days 1–2: Master the basics of arrays, strings, and linked lists.
Days 3–4: Study stacks, queues, and hash tables, focusing on their operations and use cases.
Days 5–6: Learn about trees (binary trees, binary search trees) and graphs, including basic traversal algorithms (BFS, DFS).
Days 7–8: Understand sorting and searching algorithms, like quicksort, mergesort, and binary search.
Day 9: Practice dynamic programming basics and common problems (like the Fibonacci sequence).
Day 10: Review, take mock tests, and solve a mix of problems to reinforce your understanding.

Prioritize understanding concepts and practice problems daily to build speed and confidence.