The Book
Pattern-First
Master the Patterns Behind Every Coding Interview
The 7-Layer Skill Stack
Every chapter follows the same proven structure — designed to build pattern recognition, not memorization.
The Signal
Exact keywords and constraints that fingerprint each pattern in problem statements. See the clue, know the pattern instantly.
When NOT to Use
6 boundary rules per pattern that teach you where each technique breaks down. No other book has structured per-pattern boundary guidance.
Mental Model
A beginner-vs-expert table that makes the cognitive shift visible. See what experts notice that beginners miss.
Templates with WHY
Every line of template code annotated with reasoning, not just "here's the code."
Trap Callouts
Named trap callouts on every practice problem — the specific bug most people write on their first attempt. Each has an explanation and a one-line fix.
Interview Scripts
Verbatim phrases for every problem to say out loud to your interviewer. Communication matters as much as code.
Practice Problems
Up to 5 difficulty tiers per pattern: Easy, Medium, Hard, Variant, and Pattern Combination.
Peek Inside
Every pattern distilled into a single row. Here are 5 of the 29 patterns inside.
| # | Pattern | Signal Keyword |
|---|---|---|
| 1 | Two Pointers | sorted, pair, opposite ends |
| 2 | Sliding Window | contiguous, substring, longest/shortest |
| 3 | Prefix Sum | range sum, subarray sum = k |
| 4 | Kadane's | max subarray, contiguous sum |
| 7 | Binary Search | sorted, minimize/maximize |
...and 24 more patterns inside.
Mental Model — Chapter 1: Two Pointers
| What Beginners Think | What Experts See |
|---|---|
| "I need to check every pair, so I'll use two nested loops." | "The sorted order gives me information. Each step eliminates an entire row or column of possibilities." |
| "Two pointers seems like a trick — how do I know it won't skip the answer?" | "The invariant is that all valid answers remain between the two pointers. Each move provably eliminates only impossible candidates." |
| "I'll sort first and then brute-force." | "Sorting is the investment. Two pointers is the payoff — O(n²) becomes O(n)." |
How It Compares
Pattern-First includes things no other resource does.
| Feature | Pattern-First | Typical DSA Book | LeetCode Premium |
|---|---|---|---|
| Pattern recognition signals | Yes | No | No |
| "When NOT to use" boundaries | Yes | No | No |
| Named trap callouts (every problem) | Yes | No | No |
| Interview scripts (what to say) | Yes | No | No |
| Interactive companion app | Yes | No | Partial |
| Decision tree for pattern selection | Yes | No | No |
| Study plans with daily schedule | Yes | No | No |
4 Study Plans
Pick the plan that fits your timeline. Each comes with a day-by-day study calendar.
Emergency
1 week
Top 10 (highest ROI)
Interview in days
Sprint
2 weeks
Top 10 (Tier 1)
Interview in 2 weeks
Standard
4 weeks
18 patterns (Tier 1+2)
Interview next month
Comprehensive
8 weeks
All patterns + combinations
Career-level mastery
Read Free Chapters
Try before you buy. Read the full Introduction and Chapter 1 (Two Pointers) for free — no sign-up needed.
Get Pattern-First
One purchase. Lifetime updates. Every future edition included.
One-Time Purchase
$9.99
- PDF + EPUB formats
- Every pattern chapter
- Practice problems at every level with code
- Free companion web app access
- Lifetime updates — all future editions
Frequently Asked Questions
Is this different from Grokking the Coding Interview?
Yes. Grokking groups problems by pattern but doesn't teach you how to recognize which pattern to use. Pattern-First gives you exact signal keywords, boundary rules for when NOT to use each pattern, and named trap callouts on every problem — none of which exist in Grokking.
What if I already use NeetCode or LeetCode Premium?
They complement each other. NeetCode and LeetCode Premium provide problems to practice. Pattern-First teaches the recognition skill that makes practice effective — knowing which pattern to apply before you start coding.
What language are the solutions in?
All solutions are written in idiomatic Python 3.11+. The templates and mental models are language-agnostic — you can apply them in any language.
Do I get updates?
Yes. All future updates are free. When new patterns or problems are added, you'll get the updated edition at no extra cost.
What's the refund policy?
If you're not satisfied, you can request a full refund within 30 days of purchase — no questions asked.
Stop memorizing. Start recognizing.
Every DSA pattern you need to solve 95% of coding interview problems.
Get the Book — $9.99