Ruby DSA
A lightweight execution-visualization book.
Arrays and Iteration
Array Sum (Linear Scan)
Find Maximum
Reverse Array In Place (Two Pointers)
Linear Search
Two-Sum with Hash Lookup
Sorting
Bubble Sort
Selection Sort
Insertion Sort
Merge Sort (Top-Down)
Quick Sort (Lomuto)
Searching
Binary Search (Iterative)
Binary Search (Recursive)
Binary Search First Occurrence
Linked Structures
Build a Singly Linked List
Traverse and Print
Insert at Head
Delete by Value
Reverse a Singly Linked List
Stacks and Queues
Stack Push/Pop
Balanced Parentheses
Queue Enqueue/Dequeue
Queue from Two Stacks
Hash Tables
Frequency Count
First Non-Repeating Value
Group by Key
Trees
Build a Binary Tree
Preorder Traversal
In-Order Traversal (BST)
Level-Order Traversal
BST Insert
BST Search
08-heaps
Min-Heap Insert (Sift Up)
Min-Heap Pop (Sift Down)
Top-K with a Heap
Graphs
Build a Graph as an Adjacency List
Breadth-First Search
Depth-First Search (Recursive)
Shortest Path (Unweighted, via BFS)
Recursion and Dynamic Programming
Factorial (Recursive)
Fibonacci with Memoization
Coin Change (Bottom-Up)
0/1 Knapsack (Small)