Algorithms and Data Structures
Think in Big O and solve the problems interviews actually ask.
The course that gets you through technical interviews. You will measure code in Big O by counting real operations, then implement binary search, insertion sort and merge sort, build stacks, queues and a linked list, and solve problems with hash maps, sliding windows and two pointers. You will write a binary search tree, walk graphs with BFS and DFS, and finish with the classic interview problems, graded against edge cases and efficiency budgets, while learning to talk through a solution the way interviewers expect.
What you will learn
- Big O analysis
- Binary search
- Sorting algorithms
- Stacks and queues
- Linked lists
- Hash maps
- Two pointers and sliding windows
- Trees and graphs
- Interview problem solving
Lessons
- 1
Big O
Count the work your code does, name its growth rate, and spot the hidden loops inside everyday Python operations.
8 exercises
- 2
Searching and Sorting
Binary search without off-by-one bugs, the bisect module, and insertion sort and merge sort written by hand.
8 exercises
- 3
Stacks, Queues and Linked Lists
Use a list as a stack and a deque as a queue, then build a linked list with O(1) append, search, removal and in-place reversal.
8 exercises
- 4
Hash Maps and Two Pointers
Turn O(n^2) searches into O(n) passes with dicts and sets, frequency counts, sliding windows and two pointers.
8 exercises
- 5
Recursion, Trees and Graphs
Think recursively, build a binary search tree, and explore graphs with depth-first and breadth-first search.
8 exercises
- 6
Interview Problems
Talk through a solution like a strong candidate, then solve five classic interview problems against edge cases and efficiency budgets.
5 exercises
How you practice
You practice in the browser and every exercise gives you feedback right away. This course uses these formats:
- Code exercise: 24
- Predict the output: 5
- Multiple choice: 4
- Fix the bug: 4
- Match the pairs: 2
- Select all that apply: 2
- Spot the bug: 1
- Type the answer: 1
- Fill in the blank: 1
- Reorder lines: 1
Aligned to
- Algorithmic Foundations
- AL-FoundationalFoundational Data Structures and Algorithms
- AL-ComplexityComplexity
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