Design Gurus Problem Set

How the library is organised

Instead of a single flat list, problems are indexed the way preparation actually works. You can filter by:

• Pattern: two pointers, sliding window, hash map, stack, backtracking, greedy algorithm and many more
• Data structure and topic: arrays, strings, recursion, sorting, breadth-first search and others
• Difficulty: easy, medium and hard, with an acceptance rate shown for each problem
• Company: Google, Meta, Microsoft, Amazon, Oracle and LinkedIn

Each problem page has a code editor and a solution, and your progress is tracked.

Why the organisation matters

Random practice feels productive but often is not. If interval problems are your weak spot, fifteen unrelated problems will not fix it; eight interval problems in a row will. Indexing by pattern makes targeted practice possible, and targeted practice is what turns a list of mistakes into improvement.

How to use it well

1. Keep a list of the patterns that beat you during study or mock interviews.
2. Once a week, filter by those patterns and drill only them, easy to hard.
3. Reset the list when a pattern stops causing problems, and add new weak spots as you find them.
4. Use the company filter in the final two weeks before a specific interview to focus on the kinds of problems that company asks.
5. Explain your approach aloud before coding, and check your complexity after.

Where it fits in your preparation

The problem set is best during the drilling stage, after you have learned the patterns and need repetition. A typical flow:

• Learn patterns through the Coding Interview Playbook path
• Check readiness with the Blind 75 Practice List
• Drill weak patterns and company-specific problems here
• Read the Company Interview Guides for your target company in the final weeks

What you can do afterwards

Regular, targeted drilling builds recognition speed: seeing a new problem and quickly knowing which pattern applies, then implementing it confidently. That speed is what makes the difference in a timed interview.

Common questions

Is it free? The library is free to browse. Access to individual problems and solutions is shown on each problem page.

How many problems should I do a day? Two or three focused problems with review is better than ten rushed ones.

Should I filter by company early? Company filters are most useful in the final weeks before a scheduled interview. Earlier, focus on patterns.

Best for: candidates in the drilling stage who want to practise specific patterns or prepare for a named company.