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Order the Gears

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Problem context and objectives
Mission briefing

Clockwork game engineer · A tournament scoreboard has jammed

Restore the order before the next round begins: Order the Gears.

A wrong ordering changes who advances, while a slow repair freezes every active match.

How you win

  1. 1Recognize when Sorting and partitioning matches the clues
  2. 2Keep this true after every move: the processed prefix is sorted
  3. 3Reach the result within O(n log n)

Rules and pressure

  • Target cost: O(n log n)
  • State rule: the processed prefix is sorted

New words in this mission

Open a term for a plain-language explanation.
partition or shard+

One slice of a larger dataset or workload. Splitting work raises capacity, but cross-slice operations become harder.

Lesson 1 of 3

Split the array through its middle until only one-gear pieces remain. On the way back, merge two sorted feeder lanes.

Your call · Where does [5,1,4,2] split at its midpoint?

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