Final checkpoint: mixed interview rounds
How to run the final rounds
Three rounds, real timing, and one habit that matters more than the problems.
Where you are
Nineteen teaching units and one hundred and fifty problems are behind you, forty-three of which were brought back cold in a retrieval lesson or a checkpoint, with the review queue still scheduling the rest. This module does not teach anything new.
It exists to put you under the only condition that resembles the thing you have been preparing for: a mixed set, on a clock, with nobody telling you what kind of problem you are looking at.
Key idea
Three rounds
Each round is two problems on a 45 minute clock, which is the shape of a typical onsite loop. Take a real break between rounds rather than running them together.
Nothing here is a NeetCode 150 problem, so none of it is something you have seen. Everything each one needs has been taught, and the unit each one draws on is deliberately withheld until the debrief.
Why it works
The habit that matters most
Narrate. Restate the problem, say the brute force and its cost, name the pattern you think applies and why, state your complexity before you write, and say what you are testing.
By this point the algorithms are the part you can do. What separates a good interview from a bad one with identical code is whether the interviewer could follow the reasoning, and that only improves by practicing it out loud.
If you have been skipping this through the earlier checkpoints, this is the last chance to fix it before it costs you something real.
Tip
Budget your stuckness
Five minutes of genuine stuckness, then take a nudge. Running the clock to zero with nothing written is a worse outcome than finishing with a hint, both here and in the real thing.
Note what unstuck you. Across three rounds that note is the most useful thing this module produces.