Data Structures for Coding Interviews in Java

Course Overview

Data structures are amongst the fundamentals of Computer Science and an important decision in every program. 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 o... See More

How You'll Learn

Hands-on coding environments

You don’t get better at swimming by watching others. Coding is no different. Practice as you learn with live code environments inside your browser.

Faster than videos

Videos are holding you back. The average video tutorial is spoken at 150 words per minute, while you can read at 250. That‘s why our courses are text-based.

No set-up required

Start learning immediately instead of fiddling with SDKs and IDEs. It‘s all on the cloud.

Progress you can show

Built in assessments let you test your skills. Completion certificates let you show them off.

Hands-on coding environments

You don’t get better at swimming by watching others. Coding is no different. Practice as you learn with live code environments inside your browser.

Faster than videos

Videos are holding you back. The average video tutorial is spoken at 150 words per minute, while you can read at 250. That‘s why our courses are text-based.

No set-up required

Start learning immediately instead of fiddling with SDKs and IDEs. It‘s all on the cloud.

Progress you can show

Built in assessments let you test your skills. Completion certificates let you show them off.

Course Contents

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1. Complexity Measures

Comparing Algorithms

Example 1: Measuring Time Complexity of a Single Loop Algorithm

Example 2: 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 1: Big (O) of Nested Loop with Addition

Solution Review: Big O of a Nested Loop with Addition

Challenge 2: Big (O) of Nested Loop with Subtraction

Solution Review: Big O of a Nested Loop with Subtraction

Challenge 3: Big O of Nested Loop with Multiplication

Solution Review: Big O of Nested Loop with Multiplication

Challenge 4: Nested Loop with Multiplication (Basic)

Solution Review: Nested Loop with Multiplication (Basic)

Challenge 5: Nested Loop with Multiplication (Intermediate)

Solution Review: Nested Loop with Multiplication (Intermediate)

Challenge 6: Nested Loop with Multiplication (Advanced)

Solution Review: Nested Loop with Multiplication (Advanced)

Challenge 7: Nested Loop with Multiplication (Pro)

Solution Review: Nested Loop with Multiplication (Pro)

Complexity Interview Questions

2. Arrays

What is an Array?

Two Dimensional Arrays

Challenge 1: Remove Even Integers from an Array

Solution Review: Remove Even Integers from an Array

Challenge 2: Merge Two Sorted Arrays

Solution Review: Merge Two Sorted Arrays

Challenge 3: Find Two Numbers that Add up to "n"

Solution Review: Find Two Numbers that Add up to "n"

Challenge 4: Array of Products of All Elements Except Itself

Solution Review: Array of Products of All Elements Except Itself

Challenge 5: Find Minimum Value in Array

Solution Review: Find Minimum Value in an Array

Challenge 6: First Non-Repeating Integer in an Array

Solution Review: First Non-Repeating Integer in an Array

Challenge 7: Find Second Maximum Value in an Array

Solution Review: Find Second Maximum Value in an Array

Challenge 8: Right Rotate the Array by One Index

Solution Review: Right Rotate the Array by One Index

Challenge 9: Re-arrange Positive & Negative Values

Solution Review: Re-arrange Positive & Negative Values

Challenge 10: Rearrange Sorted Array in Max/Min Form

Solution Review: Re-arrange Sorted Array in Max/Min Form

Challenge 11: Find the Sum of Maximum Sum Subarray

Solution Review: Find the Sum of Maximum Sum Subarray

Array Interview Questions

3. Linked Lists

What is the Singly Linked List (SLL)?

Basic Linked List Operations

Insertion in a Singly Linked List

Challenge 1: Insertion in a Singly Linked List (insert at End)

Solution Review: Insertion in a Singly Linked List(insert at End)

Insertion in Singly Linked List (Insert After)

Challenge 2: Search in Singly Linked List

Solution Review: Search in a Singly Linked List

Singly Linked List Deletion (Implementation)

Challenge 3: Deletion in Singly Linked List(Delete by Value)

Solution Review: Deletion in Singly Linked List

Linked Lists vs. Arrays

What is a Doubly Linked List (DLL)?

Linked List with Tail

Challenge 4: Find the Length of a Linked List

Solution Review: Find the Length of a Linked List

Challenge 5: Reverse a Linked List

Solution Review: Reverse a Linked List

Challenge 6: Detect Loop in a Linked List

Solution Review: Detect Loop in a Linked List

Challenge 7: Find the Middle Node of a Linked List

Solution Review: Find the Middle Node of a Linked List

Challenge 8: Remove Duplicates from a Linked List

Solution Review: Remove Duplicate from a Linked List

Challenge 9: Union & Intersection of Lists

Solution Review: Union & Intersection of Lists

Challenge 10: Return the Nth node from End

Solution Review: Return the Nth node from End

Challenge 11: Find if Doubly Linked-list is a Palindrome

Solution: Find if a Doubly Linked-list is a Palindrome

Linked list Interview Questions

4. Stack/Queues

What is a Stack?

Stack (Implementation)

What is a Queue?

Queue (Implementation)

Challenge 1: Generate Binary Numbers from 1 to n using a Queue

Solution Review: Generate Binary Numbers from 1 to n using Queue

Challenge 2: Implement Two Stacks using one Array

Solution Review: Implement Two Stacks using one Array

Challenge 3: Reversing the First k Elements of a Queue

Solution Review: Reversing the First k Elements of a Queue

Challenge 4: Implement Queue using Stack

Solution Review: Implement Queue using Stack

Challenge 5: Sort the Values in a Stack

Solution Review: Sort the Values in a Stack

Challenge 6: Evaluate Postfix Expressions using Stacks

Solution Review: Evaluate Postfix Expressions using Stacks

Challenge 7: Next Greater Element using Stack

Solution Review: Next Greater Element using Stack

Challenge 8: Solve a Celebrity Problem using a Stack

Solution Review: Solve a Celebrity Problem using a Stack

Challenge 9: Check for Balanced Parentheses using a Stack

Solution Review: Check for Balanced Parentheses using a Stack

Challenge 10: Create Stack where min() gives minimum in O(1)

Solution Review: Create Stack where min() gives minimum in O(1)

Stack/Queue Interview Questions

5. Graphs

What is a Graph?

Representation of Graphs

Graph Implementation

Complexities of Graph Operations

What is a Bipartite Graph?

Graph Traversal Algorithms

Challenge 1: Implement Breadth First Search

Solution Review: Implement Breadth First Search

Challenge 2: Implement Depth First Search

Solution Review: Implement Depth First Search

Challenge 3: Cycle Detection in a Directed Graph

Solution Review: Cycle Detection in a Directed Graph

Challenge 4: Find "Mother Vertex" in a Directed Graph

Solution Review: Find "Mother Vertex" in a Directed Graph

Challenge 5: Count the Number of Edges in an Undirected Graph

Solution Review: Count the number of Edges in an Undirected Graph

Challenge 6: Check if a Path Exists Between Two Vertices

Solution Review: Check if a Path Exists Between Two Vertices

Challenge 7: Check if a Directed Graph is Tree or not

Solution Review: Check if a Directed Graph is Tree or not

Challenge 8: Find Length of Shortest Path between Two Vertices

Solution Review: Find the Shortest Path between Two Vertices

Challenge 9: Remove Edge from a Directed Graph

Solution Review: Remove Edge from a Directed Graph

Graph Interview Questions

6. Trees

What is a Tree?

Types of Trees

What Makes a Tree Balanced?

What is a Binary Tree?

More on Complete Binary Trees

Skewed Binary Tree

What is a Binary Search Tree (BST)?

Insertion in Binary Search Trees

Insertion in BST (Complete Implementation)

Search in Binary Search Trees (Implementation)

Deletion in Binary Search Trees

Deletion in Binary Search Trees (Implementation)

Pre-Order Traversal in Binary Search Trees

In-Order Traversal in Binary Search Trees

Post-Order Traversal in Binary Search Tree

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 (Case #1)

2-3 Deletion (Case #2)

2-3-4 Trees

Overview of Trees

Challenge 1: Find the Minimum Value in a Binary Search Tree

Solution Review: Find the Minimum Value in a Binary Search Tree

Challenge 2: Find kth Maximum Value in a Binary Search Tree

Solution Review: Find kth Maximum Value in a Binary Search Tree

Challenge 3: Find Ancestors of Given Node in Binary Search Tree

Solution Review: Find Ancestors of a Given Node in a BST

Challenge 4: Find the Height of a Binary Search Tree

Solution Review: Find the Height of a Binary Search Tree

Challenge 5: Find Nodes at "k" Distance from the Root

Solution Review: Find Nodes at "k" Distance from the Root

Tree Interview Questions

7. Trie (Advanced Trees)

What is a Trie?

The Structure of a Trie

Insertion in a Trie

Search in a Trie

Deletion in a Trie

Challenge 1: Total Number of Words in a Trie

Solution Review: Total Number of Words in a Trie

Challenge 2: Find All of the Words in a Trie

Solution Review: Find All of the Words in a Trie

Challenge 3: Sort the Elements of an Array using a Trie.

Solution Review: Sort the Elements of an Array using a Trie.

Challenge 4: Word Formation from a Given Dictionary using a Trie

Solution Review: Word Formation from Given Dictionary using Trie

Trie Interview Questions

8. Heaps

What is a Heap

Why Use Heaps?

Heap Representation in Arrays

Max Heap: Introduction

Max Heap (Implementation)

Min Heap: An Introduction

Min Heap (Implementation)

Challenge 1: Convert a Max-Heap to a Min-Heap

Solution Review: Convert a Max-Heap to a Min-Heap

Challenge 2: Find the k Smallest Elements in an Array

Solution Review: Find the k Smallest Elements in an Array

Challenge 3: Find the k Largest Elements in an Array

Solution Review: Find the k Largest Elements in an Array

Heap Interview Questions

9. Hash Tables

What is a Hash Table?

Hash Functions

Collisions in Hash Tables

Building a Hash Table from Scratch

Add/Remove & Search in a Hash Table (Implementation)

Complete Implementation of Hash Tables

Trie vs Hash Table

HashMap vs HashSet

Challenge 1: Find whether an array is a subset of another array

Solution Review: Find whether an array is a subset of another array

Challenge 2: Check if the given arrays are disjoint

Solution Review: Check if the given arrays are disjoint

Challenge 3: Find symmetric pairs in an Array

Solution Review: Find symmetric pairs in an Array

Challenge 4: Trace the complete path of a journey

Solution Review: Trace the complete path of a journey

Challenge 5: Find two pairs in an Array such that a+b = c+d

Solution Review: Find two pairs in an Array such that a+b = c+d

Challenge 6: Find If a Subarray with a Sum Equal to 0 Exists

Solution Review: Find if a subarray with a sum equal to 0 exists.

Challenge 7: First Non-Repeating Integer in an Array

Solution Review: First Non-Repeating Integer in an Array

Challenge 8: Remove Duplicate from a Linked List using Hashing

Solution Review: Remove Duplicate from Linked List using Hashing

Challenge 9: Union and Intersection of Lists using Hashing

Solution Review: Union and Intersection of Lists using Hashing

Challenge 10: Find Two Numbers that Add up to "n"

Solution Review: Find Two Numbers that Add up to "n"

Hashing Interview Questions

10. Summary of Data Structures

Overview of Linear & Non-Linear Data Structures

Conclusion