How This Course Works

The Forge Algorithm Lab is a coding workshop built from tiers of levels. Every level asks you to write real functions or classes, and a sandboxed interpreter runs your code against hidden test cases, so it grades what your code does rather than how it looks. That is excellent practice once you can write Python fluently, and a hard place to start if you have never written a line of code. Algorithm Fundamentals (Python) is the on-ramp: a reading course that teaches the language and the thinking first, then points you at the level that puts each idea to work.

Learning to drive follows a sequence. You study the rules, you take a short written test, and then you practice in an empty car park where an examiner checks what you actually do with the wheel. This course is built the same way.

• -A chapter is the lesson on the rules.
• -The check-yourself quiz is the written test.
• -A Lab level is the car park, where hidden tests check what your code really does.
• -A Lab Bridge is the card at the end of a chapter that tells you which car-park exercise matches the lesson you just finished.

• -Phase 1, Python in Depth (course tiers 0 to 3): variables, control flow, collections, functions, object-oriented programming, errors, files, iterators and tooling. The mechanics of the language, with no prior knowledge assumed.
• -Phase 2, Algorithms (tiers 4 to 6): measuring code, then the classic structures and patterns, from stacks, hashing and sorting to trees, backtracking, dynamic programming and graphs. Its Lab Bridges point at the core data-structure levels, from the first of them up to the Tier 1 Boss, and at the sorting, tree, backtracking, dynamic programming and graph levels that end with the Tier 7 Boss.
• -Phase 3, Applied Systems Algorithms and Capstone (tier 7): the algorithms behind caches, rate limiters, security and distributed systems, bridged to levels such as LRU Cache, Token Bucket Rate Limiter, RSA Reckoning and Vector Clocks.

The lab itself goes further than the course bridges. Its remaining levels are extra practice: interview-style problems on arrays, trees, graphs and dynamic programming, and a set of object-oriented design builds such as a Parking Lot and an ATM. No chapter ends with a card for them, because each one combines ideas from several chapters. They are the natural next step once you have finished the course.

Take the Stacks & Queues module in Phase 2. You read the chapter on building a stack, then you take its short quiz, and then the chapter ends with a Lab Bridge card. A card reads something like this:

Reading builds the mental model. The lab is where that model meets a real problem and a grader that does not grade on vibes. A failed hidden test is information, not a verdict, so expect to go back and forth between the chapter and the level.

Here is a fact about the lab that shapes the whole course. Its levels are about algorithms and data structures, not about the Python language on its own. Level 2, Stack from Scratch, needs two things: the class syntax taught in the Object-Oriented Python module in Phase 1, and the idea of a stack taught in Stacks & Queues in Phase 2. So the bridge appears in the chapter that teaches the stack, once both pieces are in place. Phase 1's other chapters, on functions, errors, files, iterators and tooling, teach language skills that no level tests in isolation.

So do not be alarmed when a chapter ends without a "go build this" card. That is by design, not an oversight. When a Lab Bridge does appear, treat it as a signal: you now know enough to solve a real, graded problem, not just follow along with an example.