Master DSA from absolute zero to interview-ready. Covers Big O, arrays, trees, graphs, dynamic programming, and 120+ LeetCode problems — designed so even a kid can start and reach mastery.
Start Learning for Free →Understand how to measure code speed and memory. The foundation of everything in DSA.
The most fundamental data structure. Learn to manipulate arrays and solve classic problems.
Strings are everywhere. Learn pattern matching, reversal, and classic string problems.
The secret weapon for O(1) lookups. Hash maps solve a huge number of interview problems.
A powerful technique using two references to solve problems in O(n) time.
Process subarrays efficiently by sliding a window across the data.
Cut the search space in half every step. The key to O(log n) solutions.
Implement the most important sorting algorithms from scratch and understand their trade-offs.
Dynamic data structures where elements point to each other. A favorite in interviews.
Last-In-First-Out. Stacks power undo operations, parsing, and monotonic patterns.
First-In-First-Out. Queues model real-world lines and power BFS algorithms.
Functions that call themselves. The gateway to trees, graphs, and dynamic programming.
Hierarchical data structures. Trees appear in almost every coding interview.
Trees with a sorting property that enable O(log n) search, insert, and delete.
Always access the min/max in O(1). Heaps power scheduling and top-K problems.
Model connections between things. Learn traversal, components, and pathfinding.
Topological sort, shortest paths, and union-find for complex graph problems.
Break problems into overlapping subproblems. The most feared yet most rewarding topic.
Multi-dimensional DP for grids, strings, and sequence comparison problems.
Make the locally optimal choice at each step. Elegant solutions to optimization problems.
Explore all possibilities and backtrack when stuck. Powers combinatorial problems.
Prefix trees for lightning-fast string lookups. Powers autocomplete and spell-check.
Work directly with binary. Incredibly efficient for certain problems.
The hardest problems combining multiple techniques. If you can solve these, you're interview-ready.