Medium data structure and algorithm practice puzzle.
Given the sorted positions of servers on a hash ring and a key's position, return the position of the server that owns the key: the first server at or after the key. If the key is past the last server, wrap around to the first one. Binary search for it. Forgetting the wrap is what breaks a ring for the highest keys.
Solve it three ways: snap the jigsaw pieces together, fill in the blanks, or type it from scratch against the tests. This one is free.
Every line of the solution comes with a note explaining why it is there, and a step by step replay shows the code running. At level 3, where you type it yourself, you can ask for an AI mock interview on this problem that ends with a hiring manager's scorecard.
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