All Topics
15 topics, 50+ patterns - choose your focus area
Arrays & Strings
Foundation of DSA — master traversal, manipulation, and subarray techniques
Binary Search
Divide search space in half — sorted arrays, answer space, and rotated arrays
Sorting & Searching
Classic sorting algorithms, custom comparators, and advanced search techniques
Sliding Window & Two Pointers
Fixed and variable-width windows for substring, subarray, and two-pointer problems
Greedy
Make the locally optimal choice at each step to find the global optimum
Stacks & Queues
LIFO and FIFO structures for expression parsing, monotonic sequences, and design
Linked Lists
Pointer manipulation, in-place reversal, and fast-slow techniques
Trees & BST
Hierarchical structures — traversals, path problems, LCA, and balanced BST operations
Heaps & Priority Queue
Efficient min/max retrieval — top-K, merge K lists, and scheduling
Backtracking
Systematic exploration of all possibilities — subsets, permutations, and constraint satisfaction
Dynamic Programming
Break complex problems into overlapping subproblems — the ultimate interview topic
Tries
Prefix trees for efficient string operations — search, autocomplete, and XOR tricks
Bit Manipulation
Leverage binary operations for elegant O(1) space solutions and XOR tricks
Graphs
BFS, DFS, shortest paths, topological sort, union-find, and advanced graph algorithms
Math & Number Theory
GCD, primes, modular arithmetic, combinatorics, and mathematical patterns