Strings - Beginner → Intermediate → Advanced - TypeScript Edition

Level: Beginner → Intermediate → Advanced (all volumes in one book).

This book teaches string and data structure algorithms the way engineers actually reason through them: one character, one pointer, one decision at a time. Every pattern inside is shown three ways — a plain-language explanation of what it does and why, a real working TypeScript implementation you can compile and run yourself, and a full pictorial walkthrough that traces the index, the window, the stack, and the trie through every step.

One hundred and two algorithms span nine core patterns — Parentheses & Stack, Sliding Window, Anagrams & Character Frequency, Palindromes, Permutations, Combinations & Backtracking, Encoding & In-Place Manipulation, Pattern Matching, and Tries, Dictionaries & Word Structures, plus Dynamic Programming for Subsequences & Edit Distance. Along the way you'll build real fluency in selection, insertion, merge, and quick sort, then carry that same rigor into stacks, tries, and DP tables.

There's an old engineering joke: reach for a regular expression to solve a string problem, and you may walk away with two problems instead of one. This book is about building the instincts that tell you which one you actually need.

Every code sample was compiled, tested against edge cases beyond what's printed on the page, and independently reviewed before making it into the book. Whether you're prepping for interviews or just want string and data structure patterns to finally click, this is the reference built to make that happen.