Strivers 150 – Master Patterns in DSA

Striver's 150 – Master Patterns in DSA helps you understand the approaches that connect different coding interview problems. Instead of treating each question as a separate solution to remember, you practise recognising the structure of a problem and choosing a technique that fits.

The sheet contains 150 questions across 17 modules, with focused groups for patterns such as linear scans, prefix hashing, sliding windows, binary search on answers, monotonic stacks, tree traversals, graph exploration, and dynamic programming.

What You Will Practise

Work through arrays, hashing, two pointers, binary search, strings, stacks and queues, linked lists, binary trees, binary search trees, and heaps. Continue with recursion and backtracking, greedy algorithms, graphs, dynamic programming, tries, bit manipulation, and selected mathematics problems.

The questions range from moving zeroes and finding a missing number to designing an LRU cache, exploring graph connectivity, and solving problems such as Edit Distance and Burst Balloons.

Understand When a Pattern Applies

Study what the questions in a group have in common, what information a solution tracks, and which constraints make the approach useful. Compare related problems to understand why a small change can require a different method.

For example, searching a sorted array and finding the smallest feasible answer both use binary search, but require different reasoning. Learning that distinction helps you adapt an approach when an interview question is unfamiliar.

Build a Practice and Revision Routine

• Start with an independent attempt and describe a straightforward solution.
• Improve the approach where needed, then explain correctness and complexity.
• Use available hints, editorials, and videos to understand the gaps in your reasoning.
• Keep short notes on the pattern, its conditions, and the mistakes you made.
• Reattempt difficult questions and mix topics once you are comfortable with individual patterns.

Who Is This Sheet For?

This sheet is suitable for students preparing for placements and developers strengthening their coding interview skills. You should already know one programming language, common data structures, recursion, and basic complexity analysis. Learners starting DSA for the first time should build those foundations before using the sheet for focused practice.

Apply Your Learning in Coding Interviews

By the end, you should be better able to recognise useful patterns, choose suitable data structures, and explain the trade-offs in your solution. Practise discussing assumptions and follow-up questions so your preparation develops both implementation skills and clear technical communication.