DSA resources for developers

The official site of the ICPC, the university programming contest where teams of three share one computer for five hours and advance from regional contests towards the World Finals. It is where coaches register teams, where the current regional and World Finals rules are published, and where you find contests, results and past problems.

• DSA
• CS fundamentals

An eight-stage path from Big-O through arrays, hashing, recursion, trees, graphs, coding patterns and dynamic programming to timed, mixed practice, in Python, Java, C++ or JavaScript. It suits students and developers who can write code but freeze on problems with no obvious library call. By the end you can pick the right data structure, recognise common problem shapes and solve a medium problem in about 35 minutes with edge cases tested.

• Programming
• DSA
• Web

A quick-revision companion to the DSA roadmap in nine chapters: complexity, arrays and hashing, linked lists, stacks and queues, recursion, sorting and searching, trees and heaps, graphs, coding patterns, dynamic programming and timed practice habits. Costs are stated for every structure and algorithm, in Python, Java, C++ or JavaScript editions. Use it after each roadmap stage and before a contest or coding round.

• Programming
• DSA
• Web

A free newsletter of short, focused posts on system design and problem solving, from the team behind the Grokking courses. Recent posts cover company interview processes (such as OpenAI and Anthropic roles), the most asked mobile system design questions and preparation plans, each linking to a fuller article on the blog. It suits engineers who want a steady, low-effort way to keep system design and interview topics fresh between deeper study sessions.

• System design
• DSA

A long running YouTube channel where university researchers and practitioners explain computer science topics in short videos, from hashing, compression and cryptography to floating point, AI and security. It is produced with the University of Nottingham and suits self-taught developers and students who want to fill theory gaps casually, without committing to a course.

• CS fundamentals
• DSA

A pattern-based coding interview course covering 31 common and 11 advanced patterns such as sliding window, two pointers, merge intervals, cyclic sort, top K elements, topological sort, union find and segment trees, with more than 300 problems solved in six languages. Instead of memorising solutions, you learn to map a new question to a known pattern. It suits anyone with working data structures knowledge who freezes on unfamiliar questions.

• Job search
• DSA

A foundations course that builds eleven core data structures from the ground up (arrays, matrices, stacks, queues, linked lists, trees and BSTs, hash tables, hash sets, heaps, graphs and tries), then covers sorting, searching, greedy and divide and conquer. Every chapter has practice problems, flashcards and an assessment. It suits students and career switchers whose foundations came from tutorials and who find pattern courses move too fast.

• Job search
• DSA
• CS fundamentals

A structured learning path through coding interview preparation that brings together data structures and algorithms fundamentals, recursion and the pattern-based approach to coding questions in one order. It totals 77 chapters and 1,054 lessons, with quizzes, flashcards and a certificate. Use it when you have plenty of material but no clear plan for what to study first.

• Job search
• DSA
• Career

A bundle of five company-specific question courses covering the problems most often reported from Meta, Microsoft, Amazon, Google and Oracle coding rounds, each split into easy, medium and hard sets with worked solutions. It suits candidates who already know the core patterns and have a loop booked at one of these companies, and want to rehearse on the questions those interviewers are known to ask.

• Job search
• DSA
• Career

A dynamic programming course organised around five patterns: 0/1 knapsack, unbounded knapsack, Fibonacci numbers, palindromic subsequence and longest common substring. Each of its 35 problems is solved three ways, as plain recursion, top-down with memoization, and bottom-up tabulation. It suits candidates who can handle most interview topics but stall on DP because they cannot find the recurrence.

• Job search
• DSA

A course built around 75 coding interview questions chosen for coverage across 18 topic areas, from arrays and sliding window to graphs, backtracking, dynamic programming and tries. Each question has a step-by-step algorithm, a walkthrough and complexity analysis, with solutions in six languages. It suits candidates with a few weeks before an interview who need a balanced, finite problem set rather than an endless list.

• Job search
• DSA

A short text course on algorithm analysis: all five asymptotic notations, time and space complexity, best, worst and average cases, and three methods for recursive complexity including the master theorem. It suits students and self-taught developers who can write working code but freeze when an interviewer asks for the time and space complexity, or who want to understand why one solution is faster than another.

• Job search
• DSA
• CS fundamentals

A graph-only course that starts with representations, BFS and DFS, then covers matrix graphs, graph theory, union find, topological sort, shortest paths (Dijkstra, Bellman-Ford, Floyd-Warshall) and minimum spanning trees (Kruskal, Prim, Boruvka). It has 50 problems with walkthroughs in six languages. It suits candidates comfortable with trees who keep losing marks on graph questions or fail to recognise a graph hidden inside a grid or dependency list.

• Job search
• DSA

A course that organises tree interview questions into nine patterns: level order traversal, tree depth, BFS, DFS, root to leaf paths, leaf processing, tree views, comparing two trees, and serialize and deserialize. It has 49 problems with walkthroughs and complexity analysis in six languages. It suits candidates whose tree solutions work on simple cases but break on edge cases, or who want trees covered in more depth than a general course offers.

• Job search
• DSA

A recursion course that explains the call stack, base cases, recursion types and recursion versus iteration, then works through 19 problems from factorial and GCD to binary search, merge sort, quick sort, DFS, BST operations, memoized Fibonacci and Pow(x, n). Solutions come in six languages with diagrams and complexity analysis. It suits students and self-taught developers who avoid recursive solutions or trace every call by hand because they do not trust them.

• Job search
• DSA
• CS fundamentals

A browsable practice library of coding problems that can be filtered by pattern, data structure, difficulty and company, so you can drill exactly the weakness you found this week. Patterns include two pointers, sliding window, hash maps, stacks, backtracking and greedy algorithms, with company filters for Google, Meta, Microsoft, Amazon, Oracle and LinkedIn. Free to browse, with an in-browser editor and solutions.

• Job search
• DSA

The well-known Blind 75 interview problem list, grouped into five topic areas with a difficulty level, a practice link and a step-by-step solution for each problem. Free to use, with hints, an in-browser coding workspace, notes and progress tracking. A focused way to cover the most frequently asked problem types and to check whether your preparation is working.

• Job search
• DSA

The classic textbook on how search engines work, by Manning, Raghavan and Schutze, with the full text free to read online. Inverted indexes, tokenisation, scoring, tf-idf and evaluation explained from first principles.

• CS fundamentals
• DSA

A quick-revision companion to the Sefism competitive programming roadmap, in ten chapters from C++ for contests to team play and ICPC: complexity tables, a contest template, STL snippets, maths, greedy, binary search, prefix sums, graphs, DP and range data structures, each with the classic mistake. It comes in beginner, intermediate and advanced editions matched to your rating. Use it between contests to revise a technique, copy a clean template and spot the bug before the judge does.

• DSA
• Programming
• CS fundamentals

A ten-stage plan for playing competitive programming as a sport on Codeforces, AtCoder and in the ICPC: contest C++ and the STL, maths, greedy, binary search, prefix sums, graphs, DP, range data structures, contest strategy and team play. You pick a starting level (under 1200, 1200 to 1600, or 1600 and above) and the topics adjust to it. It suits university students who already code and want to compete; by the end you can write fast, correct C++ under a timer, upsolve after every round and play a five-hour team contest with a plan.

• DSA
• Programming
• CS fundamentals

A free, open source guide that organises competitive programming topics by USACO division, from Bronze to Platinum and beyond, with explanations, code and curated practice problems for each module. Built by the student-run Competitive Programming Initiative, it is one of the clearest step-by-step paths through contest algorithms, whether or not you ever enter USACO.

• DSA

KTH's open ICPC team reference document: about 25 pages of short, tested, copy-pasteable C++ for data structures, graphs, number theory, geometry and strings, kept within the World Finals notebook limit. Teams around the world print it as is or use it as the starting point for their own notebook.

• DSA

A free collection of classic competitive programming problems, grouped by topic from introductory problems and sorting to graphs, range queries, trees, maths and strings. Each problem teaches one standard technique cleanly, which makes it the most widely recommended checklist for building a contest toolkit. Pairs with the free Competitive Programmer's Handbook.

• DSA
• CS fundamentals

A free, volunteer-run encyclopedia of algorithms and data structures used in competitive programming, with clear explanations, proofs and C++ implementations for everything from the sieve and binary exponentiation to segment trees, LCA and string algorithms. Started as an English translation of the Russian site e-maxx and has grown well beyond it.

• DSA
• CS fundamentals