Master DSA Visually

▭

Sliding Window

Fixed and variable window over a contiguous subarray

0/2

Max Average Subarray I

Best Time to Buy & Sell Stock

⌗

Binary Search

Halve the search space each iteration

0/28

Binary Search

Search Insert Position

Find Min in Rotated Array

Floor and Ceil in Sorted Array

First and Last Occurrence

Search in Rotated Sorted Array

Search in Rotated Sorted Array II

Count Rotations in Sorted Array

Single Element in Sorted Array

Square Root of a Number

Minimum Days to Make M Bouquets

N-th Root of a Number

Aggressive Cows

Book Allocation Problem

Split Array — Largest Sum

Minimise Max Distance to Gas Station

Median of Two Sorted Arrays

K-th Element of Two Sorted Arrays

Search in a 2D Matrix

Search in a 2D Matrix II

Find Row with Maximum 1s

↕

Sorting

Classic comparison-based sorting algorithms

0/3

▤

Stack

LIFO structure & monotonic-stack techniques

0/15

Next Greater Element

Next Greater Element II

Asteroid Collision

Sum of Subarray Minimums

Largest Rectangle in Histogram

Sum of Subarray Ranges

Sliding Window Maximum

↻

Recursion

Reduce a problem to smaller versions of itself

0/17

Subsequence Sum Exists

Count Subsequences with Sum K

Letter Combinations of a Phone Number

Palindrome Partitioning

⛓

Linked List

Relink nodes in place with pointer bookkeeping

0/18

Reverse a Linked List

Find Middle of Linked List

Merge Two Sorted Lists

Delete the Middle Node

Sort a Linked List

Sort a Linked List of 0s, 1s and 2s

Remove N-th Node from the End

Add One to a Number

Add Two Numbers in Linked List

Segregate Odd and Even Nodes

Detect a Loop

Find the Loop's Starting Point

Length of the Loop

Check if a List is a Palindrome

Intersection of Two Lists

Rotate a Linked List

Reverse in Groups of K

Flatten a Linked List

⑂

Trees

Hierarchical data structures and traversal algorithms

0/2

Level Order Traversal

Pre, In & Postorder Traversal

Graphs

Traverse connected nodes and edges efficiently

0/8

Dijkstra's Shortest Path

Kruskal's Minimum Spanning Tree

Prim''s Minimum Spanning Tree

Topological Sort

Bellman-Ford Shortest Path

Floyd-Warshall All-Pairs Paths

Language & Runtime

Core JavaScript

Call stack, event loop, microtasks — the language runtime itself

0/6

Execution Model

Call Stack Basics

Sync, Microtask, Macrotask — What Prints First?new

Event Loop & Output Order

Two Promise Chains — Why They Interleavenew

async / await Output Ordernew

setTimeout in a Loop — var vs letnew

useCounter — Custom Hook Anatomynew

React Hooks

process.nextTick vs Promise Microtasksnew

⬢

Node.js Runtime

libuv phases, nextTick, setImmediate, timers and file I/O ordering

0/4

Microtask Queues

setImmediate vs setTimeout(fn, 0)new

Phases, Immediates & I/O

fs.readFile and the Poll Phasenew

hard

Timers

setInterval, setTimeout and the Timers Phasenew