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DSA

Data Structures & Algorithms

Arrays, linked lists, trees, graphs, sorting, searching and dynamic programming, from Big-O basics to master-level structures. Every algorithm explained with step-by-step visuals and C# code.

0 of 50 lessons completed · 50 topics in the full course Start learning: What are data structures and algorithms?

Beginner

1. Foundations

5 topics

What are data structures and algorithms?Lesson
Measuring speed: Big-O notationLesson
Counting steps in real codeLesson
Memory cost: space complexityLesson
Recursion, call trees and memoisationLesson

Beginner

2. Linear data structures

6 topics

Arrays in memoryLesson
Dynamic arrays: how List<T> growsLesson
Singly linked listsLesson
Doubly and circular linked listsLesson
Stacks and their usesLesson
Queues, circular buffers and dequesLesson

Intermediate

3. Searching and sorting

7 topics

Linear search and binary searchLesson
Binary search: bounds and searching for answersLesson
Bubble, selection and insertion sortLesson
Merge sortLesson
Quick sortLesson
Counting sort and radix sortLesson
Sorting in .NET: stability and comparersLesson

Intermediate

4. Hashing and problem-solving techniques

6 topics

How hash tables workLesson
Solving problems with HashSet and DictionaryLesson
Two pointersLesson
Sliding windowLesson
Prefix sums and difference arraysLesson
Bit manipulationLesson

Intermediate

5. Trees

6 topics

Trees and binary treesLesson
Tree traversals: pre, in, post and level orderLesson
Binary search treesLesson
Balanced trees: AVL, red-black and B-treesLesson
Heaps and priority queuesLesson
Tries (prefix trees)Lesson

Advanced

6. Graphs

8 topics

Graphs and how to store themLesson
Breadth-first searchLesson
Depth-first searchLesson
Topological sortLesson
Shortest paths: DijkstraLesson
Bellman-Ford and Floyd-WarshallLesson
Minimum spanning treesLesson
Union-find (disjoint sets)Lesson

Advanced

7. Algorithm design

6 topics

Greedy algorithmsLesson
Divide and conquerLesson
BacktrackingLesson
Dynamic programming: the ideaLesson
Dynamic programming: grids and sequencesLesson
Dynamic programming: knapsack, LCS and edit distanceLesson

Master

8. Master level

6 topics

Segment trees and Fenwick treesLesson
String matching: KMP and Rabin-KarpLesson
Spatial indexes: grids, quadtrees and BVHLesson
Computational geometry basicsLesson
Hard problems: P, NP and approximationLesson
How to solve any DSA problemLesson