Heapsort

Build a max-heap and repeatedly place its maximum at the end of the remaining range.

Remember: Heap root → sorted suffix.

Example: [2,3,1] → heap [3,2,1] → [2,1,3] → [1,2,3].

Time: O(n log n). Auxiliary space: O(1).

Formula: Build max-heap O(n); repeatedly swap root to end and sift down

Up to 15 integers. Iterative sift-down, unstable. The sorted suffix grows from the right. Not the same operation as merely building a heap.

Complexities describe the underlying algorithm; tutorial snapshots and rendering can use additional resources.

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