Coding interview exercises
Coding interview exercises
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Five minutes, start to finish: reading the task, asking the interviewer, running tests, fixing two bugs and the questions at the end. Prefer to read? The same steps, written out.
A concert sale sold out, but only a third of the seats were ever paid for.
Model students and their 0-100 scores, and compute each student's average and letter grade.
An account-lockout guard that stops password guessing is live, and users say it locks them out when it shouldn't.
Build billing for a parking garage where each vehicle type is charged by its own rate rule.
Listen to a live stream of JSON position messages from buses driving fixed routes of stations on a grid.
Scan a tree of files and directories where permissions are inherited from the nearest ancestor that sets one.
A sliding-window rate limiter that caps each user's requests per time window is already live in production.
Design a hub for independent building sensors (temperature, motion, door) that report readings as values change.
You're on call for an in-house load balancer that spreads API traffic across a pool of backend servers.
Route notifications to each user through their preferred channel, such as email, SMS or push.
Build a supermarket checkout that scans products and reports the running cart total at any point.