A systematic, pattern-first companion repository inspired by the Big Tech DSA Coding Interview curriculum. Includes all 14 foundational-to-advanced pattern chapters, complete with clean Python 3 solutions, formal Big-O analysis, UMPIRE interview guides, and executable test suites.
- 📖 0.1 Foreword & How to Use This Book — 3 reading paths (Sequential, Pattern-based, Last-minute cramming).
- 🧩 0.2 The UMPIRE Interview Framework — 6-step problem-solving system: Understand ➜ Match ➜ Plan ➜ Implement ➜ Review ➜ Evaluate.
- ⏱️ 0.3 Big-O in 30 Minutes — Asymptotic analysis, amortized complexity, practical constraint bounds.
- 🐍 0.4 Python 3 Cheatsheet for Interviews — Data structures, syntax, heap tricks, and critical pitfalls.
- 🎤 0.5 Whiteboard & CoderPad Presentation Guide — Communication etiquette, thinking out loud, and handling hints.
| Chapter | Topic & Core Pattern | Difficulty | Key Problems & Solutions | Code & Study Guide |
|---|---|---|---|---|
| 01 | Chapter 1 — Array | 🟢 Basic |
Two Sum, Stock Profit, Product Except Self, Kadane's | Open Chapter 📂 |
| 02 | Chapter 2 — String | 🟢 Basic |
Valid Anagram, Palindrome, Longest Substring Window | Open Chapter 📂 |
| 03 | Chapter 3 — Recursion | 🟡 Intermediate |
Climbing Stairs Memoization, Subsets (Power Set) | Open Chapter 📂 |
| 04 | Chapter 4 — Sorting | 🟡 Intermediate |
Merge Sort, Dutch National Flag (Sort Colors) | Open Chapter 📂 |
| 05 | Chapter 5 — Binary Search | 🟡 Intermediate |
Classic Binary Search, Rotated Array Search | Open Chapter 📂 |
| 06 | Chapter 6 — Hash Table | 🟢 Basic |
Longest Consecutive Sequence, Subarray Sum Equals K | Open Chapter 📂 |
| 07 | Chapter 7 — Linked List | 🟡 Intermediate |
Reverse Linked List, Floyd's Tortoise & Hare Cycle | Open Chapter 📂 |
| 08 | Chapter 8 — Queue + Stack | 🟡 Intermediate |
Valid Parentheses, Daily Temperatures Monotonic Stack | Open Chapter 📂 |
| 09 | Chapter 9 — Graph | 🔴 Advanced |
Clone Graph, Disjoint Set Union (Union-Find) | Open Chapter 📂 |
| 10 | Chapter 10 — Breadth-First Search (BFS) | 🟡 Intermediate |
Tree Level-Order, Shortest Path in Binary Matrix | Open Chapter 📂 |
| 11 | Chapter 11 — Depth-First Search (DFS) | 🟡 Intermediate |
Course Schedule 3-State Cycle Detection | Open Chapter 📂 |
| 12 | Chapter 12 — Island Matrix Traversal | 🟡 Intermediate |
Number of Islands DFS, Rotting Oranges Multi-Source BFS | Open Chapter 📂 |
| 13 | Chapter 13 — Topological Sort | 🔴 Advanced |
Kahn's Indegree Algorithm (Course Schedule II) | Open Chapter 📂 |
| 14 | Chapter 14 — Interval | 🟡 Intermediate |
Merge Intervals, Meeting Rooms II Minimum Allocation | Open Chapter 📂 |
- GitHub: @preyal2
- Repository: preyal2/coding-interview-patterns
- Original Authors & Inspiration: Phạm Ngọc Lâm & Lê Quang Hoà (EngineerPro Coding Book)