Data Structures

Arrays

Lists vs Arrays in Python

Challenge: Remove Even Integers From List

Solution: Remove Even Integers From List

Challenge: Merge Two Sorted Lists

Solution: Merge Two Sorted Lists

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 List

Solution: Find Minimum Value in List

Challenge: First Non-Repeating Integer in a List

Solution: First Non-Repeating Integer in a List

Challenge: Find Second Maximum Value in a List

Solution: Find Second Maximum Value in a List

Challenge: Rotate List

Solution: Rotate List

Challenge: Rearrange Positive & Negative Values

Solution: Rearrange Positive & Negative Values

Challenge: Rearrange Sorted List in Max/Min Form

Solution: Rearrange Sorted List in Max/Min Form

Challenge: Maximum Sublist

Solution: Maximum Sublist

Linked Lists vs. Lists

Basic Linked List Operations

Singly Linked List Insertion

Challenge: Insertion at Tail

Solution: Insertion at Tail

Challenge: Search in a Singly Linked List

Solution: Search in a Singly Linked List

Singly Linked List Deletion

Challenge: Deletion by Value

Solution: Deletion by Value

Doubly Linked Lists (DLL)

Singly Linked Lists vs. Doubly Linked Lists

Challenge: Find the Length of a Linked List

Solution: Find the Length of a Linked List

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

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 List

Solution: Implement Two Stacks Using One List

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: Valid Parentheses

Solution: Valid Parentheses

Challenge: Min Stack

Solution: Min Stack

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

What makes a tree 'balanced'?

What is a Binary Tree?

More on Complete Binary Trees

Skewed Binary Trees

What is a Binary Search Tree (BST)?

Implementing a Binary Search Tree in Python

Binary Search Tree Insertion

Binary Search Tree Insertion (Implementation)

Searching in a Binary Search Tree (Implementation)

Deletion in a Binary Search Tree

Deletion in a Binary Search Tree (Implementation)

Pre-Order Traversal

Post-Order Traversal

In-Order Traversal

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: 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

Structure of a Trie

Insertion in a Trie

Search in a Trie

Deletion in Trie

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: List Sort Using Trie

Solution: List Sort Using Trie

Challenge: Word Formation From a Dictionary Using Trie

Solution: Word Formation From a Dictionary Using Trie

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 a List

Solution: Find k Smallest Elements in a List

Challenge: Find K Largest Elements in the List

Solution: Find K Largest Elements in the List

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 Table

Dictionary vs Set

Challenge: A List as a Subset of Another List

Solution: A List as a Subset of Another List

Challenge: Check if Lists are Disjoint

Solution: Check if Lists are Disjoint

Challenge: Find Symmetric Pairs in a List

Solution: Find Symmetric Pairs in a List

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 Sublist with a Sum of 0

Solution: A Sublist 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 a List—Hashing

Solution: First Non-Repeating Integer in a List—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