TopicsDSA & Algorithms
DSA & Algorithms
Interview pattern map — arrays to DP/backtracking — with Big-O, templates, and LeetCode drills.
Common tags: dsa, algorithms, leetcode, patterns, big-o
- DSA & Algorithms
Union-Find (Disjoint Set Union) — Connectivity, Components & Kruskal
Cluster · DSA Interview Patterns
DSU with path compression and union-by-rank for dynamic connectivity.
Open study →- dsa
- algorithms
- interview
- leetcode
- union-find
- dsu
- graphs
- DSA & Algorithms
Tries / Prefix Trees
Cluster · DSA Advanced & Company Favorites
Prefix trees for autocomplete, Word Search II, and dictionary prefix queries with O(L) ops.
Open study →- dsa
- trie
- prefix-tree
- strings
- interview
- DSA & Algorithms
Binary Trees — DFS (Preorder, Inorder, Postorder; Recursion & Stack)
Cluster · DSA Interview Patterns
Tree DFS orders with recursion and explicit stack; path and subtree aggregates.
Open study →- dsa
- algorithms
- interview
- leetcode
- trees
- dfs
- binary-tree
- DSA & Algorithms
Binary Trees — BFS / Level Order — Layers, Width & Zigzag
Cluster · DSA Interview Patterns
Level-order BFS for layers, width, zigzag, and closest-value-by-depth.
Open study →- dsa
- algorithms
- interview
- leetcode
- trees
- bfs
- binary-tree
- DSA & Algorithms
Trees Advanced - LCA, Rerooting, Path aggregates
Cluster · DSA Advanced & Company Favorites
LCA binary lifting intuition, rerooting DP, and path aggregates on trees.
Open study →- dsa
- trees
- lca
- rerooting
- interview
- DSA & Algorithms
Coding-round System Design Lite - rate limiter, URL shortener coding shapes
Cluster · DSA Advanced & Company Favorites
Coding-round shaped designs: rate limiter, URL shortener, tiny LFU/cache - not full HLD.
Open study →- dsa
- system-design-lite
- rate-limiter
- interview
- DSA & Algorithms
Strings - Parsing, Rolling Hash & KMP intuition
Cluster · DSA Advanced & Company Favorites
String parsing patterns, Rabin-Karp rolling hash, and KMP LPS intuition for interviews.
Open study →- dsa
- strings
- kmp
- rolling-hash
- interview
- DSA & Algorithms
Stack & Monotonic Stack — Next Greater, Histograms & Parsing
Cluster · DSA Interview Patterns
Monotonic stacks for next-greater/smaller, histogram areas, and expression parsing.
Open study →- dsa
- algorithms
- interview
- leetcode
- stack
- monotonic-stack
- DSA & Algorithms
Sorting, Intervals & Sweep Line — Merge, Overlap & Events
Cluster · DSA Interview Patterns
Sort plus sweep for merge intervals, overlaps, and event-based line sweeps.
Open study →- dsa
- algorithms
- interview
- leetcode
- sorting
- intervals
- sweep-line
- DSA & Algorithms
Sliding Window — Fixed & Variable Windows for Subarrays
Cluster · DSA Interview Patterns
Fixed and variable sliding windows for subarray/substring constraints in O(n).
Open study →- dsa
- algorithms
- interview
- leetcode
- sliding-window
- arrays
- DSA & Algorithms
Shortest Paths — Dijkstra, Bellman-Ford & When Not To Use Them
Cluster · DSA Interview Patterns
Dijkstra vs Bellman-Ford vs BFS-on-unweighted; negative edges and when not to.
Open study →- dsa
- algorithms
- interview
- leetcode
- graphs
- shortest-path
- dijkstra
- bellman-ford
- DSA & Algorithms
Recursion & Divide-and-Conquer - Master theorem intuition, merge patterns
Cluster · DSA Advanced & Company Favorites
Divide-and-conquer templates, merge patterns, Master theorem intuition for interview analysis.
Open study →- dsa
- recursion
- divide-conquer
- interview
- DSA & Algorithms
Queue, Deque & Monotonic Queue — Sliding Extrema & BFS Helpers
Cluster · DSA Interview Patterns
Deque and monotonic queue for sliding-window maxima and BFS-friendly fronts.
Open study →- dsa
- algorithms
- interview
- leetcode
- queue
- deque
- monotonic-queue
- DSA & Algorithms
Prefix Sums & Difference Arrays — Range Queries in O(1)
Cluster · DSA Interview Patterns
Prefix sums and difference arrays for range sums and range updates.
Open study →- dsa
- algorithms
- interview
- leetcode
- prefix-sums
- difference-array
- arrays
- DSA & Algorithms
Mock Interview Drills - timed sets by company theme + checklist
Cluster · DSA Advanced & Company Favorites
Timed mock sets by company theme (Meta/Amazon/Google-style) plus checklist and wave-1+2 coverage map.
Open study →- dsa
- mock-interview
- faang
- drill
- DSA & Algorithms
Matrix Traversal - Spiral, Islands, DFS/BFS on grids
Cluster · DSA Advanced & Company Favorites
Spiral order, rotate, islands variants, and grid BFS/DFS depth beyond basic flood fill.
Open study →- dsa
- matrix
- grid
- bfs
- dfs
- interview
- DSA & Algorithms
Math & Number Theory for Interviews (gcd, mod, primes, combinatorics basics)
Cluster · DSA Advanced & Company Favorites
gcd/lcm, modular arithmetic, primes/sieve, and combinatorics basics asked in coding rounds.
Open study →- dsa
- math
- number-theory
- interview
- DSA & Algorithms
Linked Lists — Reverse, Merge, Cycle Detection & Dummy Heads
Cluster · DSA Interview Patterns
In-place reverse, merge, Floyd cycle, and dummy-head patterns for list surgery.
Open study →- dsa
- algorithms
- interview
- leetcode
- linked-list
- DSA & Algorithms
DSA for Interviews — Pattern Map, Complexity & How to Drill
Cluster · DSA Interview Patterns
Interview DSA pattern map, Big-O cheat sheet, how to pick a pattern, and drill pacing for 20 core patterns.
Open study →- dsa
- algorithms
- interview
- leetcode
- patterns
- big-o
- DSA & Algorithms
DSA Advanced & Company Favorites - Tries, Greedy, Strings, Design & More
Cluster · DSA Advanced & Company Favorites
Advanced company-favorite DSA patterns beyond the fundamentals track: tries, bits, greedy, strings, DP advanced, design, concurrency, and mock drills.
Open study →- dsa
- algorithms
- interview
- leetcode
- faang
- patterns
- DSA & Algorithms
Intervals Advanced - Meeting Rooms, Merge, Sweep Priorities
Cluster · DSA Advanced & Company Favorites
Meeting rooms, merge intervals, employee free time, and sweep-line priority queues.
Open study →- dsa
- intervals
- sweep-line
- interview
- DSA & Algorithms
Heaps, Priority Queues & Top-K — n-largest, Merge K & Streaming
Cluster · DSA Interview Patterns
Min/max heaps for top-K, merge K lists, and streaming extremes.
Open study →- dsa
- algorithms
- interview
- leetcode
- heaps
- priority-queue
- top-k
- DSA & Algorithms
Hashing, Frequency Maps & Counting — Two Sum Family & Anagrams
Cluster · DSA Interview Patterns
Hash maps for complements, frequency, anagrams, and O(1) expected lookups.
Open study →- dsa
- algorithms
- interview
- leetcode
- hashing
- hashmap
- counting
- DSA & Algorithms
Greedy Algorithms - Proof Sketches & Exchange Arguments
Cluster · DSA Advanced & Company Favorites
When greedy works: exchange arguments, stay-ahead proofs, and classic interview greeds.
Open study →- dsa
- greedy
- interview
- proof
- DSA & Algorithms
Graphs — Topological Sort & DAGs — Kahn, DFS Finish Times & Cycles
Cluster · DSA Interview Patterns
Kahn and DFS topo sort on DAGs; detect cycles and order dependencies.
Open study →- dsa
- algorithms
- interview
- leetcode
- graphs
- topological-sort
- dag
- DSA & Algorithms
Graphs — DFS & BFS Traversal — Components, Cycles & Grid Flood
Cluster · DSA Interview Patterns
Graph DFS/BFS for components, cycles, bipartite checks, and grid flood fill.
Open study →- dsa
- algorithms
- interview
- leetcode
- graphs
- dfs
- bfs
- DSA & Algorithms
Graphs Advanced - SCC, Bridges, Articulation, Bipartite
Cluster · DSA Advanced & Company Favorites
Tarjan/Kosaraju SCC, bridges, articulation points, and bipartite coloring for advanced graph rounds.
Open study →- dsa
- graphs
- scc
- bridges
- bipartite
- interview
- DSA & Algorithms
DP Advanced - State machine DP, Digit DP intro, Interval DP, Bitmask DP
Cluster · DSA Advanced & Company Favorites
State-machine DP, digit DP intro, interval DP, and bitmask DP for harder company rounds.
Open study →- dsa
- dp
- bitmask-dp
- interval-dp
- interview
- DSA & Algorithms
Dynamic Programming — 2D, Knapsack & Grids — Paths, Subsets & LCS
Cluster · DSA Interview Patterns
2D DP for grids, 0/1 knapsack, LCS/edit distance, and space-optimized rolls.
Open study →- dsa
- algorithms
- interview
- leetcode
- dp
- dynamic-programming
- knapsack
- 2d-dp
- DSA & Algorithms
Dynamic Programming — 1D Patterns — Climb, House Robber, LIS Families
Cluster · DSA Interview Patterns
1D DP templates: recurrence, rolling arrays, and classic climb/robber/LIS shapes.
Open study →- dsa
- algorithms
- interview
- leetcode
- dp
- dynamic-programming
- 1d-dp
- DSA & Algorithms
Design Data Structures - LRU/LFU, MinStack, Snapshot, RandomizedSet
Cluster · DSA Advanced & Company Favorites
Design coding favorites: LRU/LFU, MinStack, Snapshot Array, RandomizedSet with O(1) targets.
Open study →- dsa
- design
- lru
- lfu
- interview
- DSA & Algorithms
Concurrency Interview Basics - locks, barriers, bounded buffer
Cluster · DSA Advanced & Company Favorites
LeetCode concurrency patterns: locks, barriers, bounded buffer, print-in-order style problems.
Open study →- dsa
- concurrency
- multithreading
- interview
- DSA & Algorithms
Bit Manipulation & Bitmasks
Cluster · DSA Advanced & Company Favorites
Bit tricks, XOR family, subset bitmasks, and when FAANG asks bit puzzles.
Open study →- dsa
- bits
- bitmask
- interview
- DSA & Algorithms
Binary Search & Search-on-Answer — Predicates, Bounds & Feasibility
Cluster · DSA Interview Patterns
Classic binary search plus search-on-answer over monotonic feasibility predicates.
Open study →- dsa
- algorithms
- interview
- leetcode
- binary-search
- search-on-answer
- DSA & Algorithms
Binary Search Trees — Inorder, Bounds, LCA & Validate
Cluster · DSA Interview Patterns
BST invariants: inorder sortedness, insert/delete sketch, validate, and LCA.
Open study →- dsa
- algorithms
- interview
- leetcode
- trees
- bst
- binary-search-tree
- DSA & Algorithms
Backtracking & Search Trees — Subsets, Permutations, Combinations & Pruning
Cluster · DSA Interview Patterns
Backtracking templates with choose/explore/unchoose and pruning for interviews.
Open study →- dsa
- algorithms
- interview
- leetcode
- backtracking
- recursion
- search
- DSA & Algorithms
Arrays & Two Pointers — Opposite Ends, Same Direction & Partition
Cluster · DSA Interview Patterns
Opposite-end and same-direction two pointers for sorted arrays, partitions, and O(n) pair scans.
Open study →- dsa
- algorithms
- interview
- leetcode
- arrays
- two-pointers