01
Core pattern fluency
Arrays, strings, and search — the building blocks every loop opens with.
- Two pointer, sliding window, and prefix sums
- Hashing, greedy tricks, and binary search
- Stack, queue, and linked list fundamentals
DSA · Pattern-first coding interview prep
DSAbyPatterns
Pattern-first problem lists — arrays, trees, graphs, and DP with LeetCode links and company tags.
Panels reward recognizing patterns fast — not grinding hundreds of random problems.
Learn the pattern, nail the loop. Drill topic-by-topic — free to start.
Free topic lists · LeetCode links · Company tags
What you'll master
Core patterns, advanced topics, and curated lists aligned with real coding interviews.
02
Trees, graphs & DP
The patterns mid-level and senior panels expect you to recognize fast.
- DFS/BFS on trees and graphs
- Dynamic programming families and recurrence
- Heaps, greedy intervals, and shortest path
03
Interview-ready lists
Curated problems that mirror real company loops — not random grinding.
- Pattern-labeled problems with summaries
- LeetCode links and company tags
- Topic-wise lists you can drill in order
Explore topics
10 DSA topics with the patterns covered in each problem list.
| # | Topic | Patterns |
|---|---|---|
| 1 | Array | Two Pointer, Sliding Window, Prefix Sum, Kadane’s Algorithm, Greedy/Hashing, Matrix, Monotonic Stack, In-place Transformations |
| 2 | String | Sliding Window, Hashing, Two Pointer, Trie / Prefix Tree |
| 3 | Binary search | Classic Binary Search, Binary Search on Answer, Rotated Sorted Array, Finding Boundaries |
| 4 | Linked list | Fast & Slow Pointer, Reversal, Merge Two Lists, Cycle Detection |
| 5 | Stack & queue | Balanced Parentheses, Next Greater Element, Stack as Recursion Simulator, Histogram / Largest Rectangle, Sliding Window, Circular Queue / Ring Buffer, First Unique Character |
| 6 | Binary tree | DFS / BFS, Lowest Common Ancestor, Balanced Tree Check, Binary Search Tree, Tree Diameter |
| 7 | Dynamic programming | Knapsack, Longest Common Subsequence, Coin Change, Fibonacci / Recurrence, Subset Sum, DP on Trees |
| 8 | Graph | DFS / BFS, Cycle Detection, Topological Sort, Shortest Path, Union Find / Disjoint Set |
| 9 | Greedy | Activity Selection, Huffman Coding, Job Scheduling, Interval Merging |
| 10 | Heap | Min/Max Heap, Kth Largest/Smallest, Merge K Sorted Lists, Sliding Window Max |
Practice machine coding
After the lists—rehearse JavaScript and React challenges in the live editor with automated tests.
Machine coding practice
Real interview-style problems in the browser—write code, run tests, and mark challenges solved on your profile.
- JS & React machine coding challenges
- In-editor tests and starter templates
- Profile dashboard for solved progress