What is 'Sift Down' in a heap?
What is 'Sift Down' in a heap?
Approach: Describe moving an element down to its correct position.
If a node is larger (in a min-heap) than its children, it is swapped with its smallest child. This repeats until the heap property is restored.
Follow-up: When is this operation used? (e.g., extract-min)
Key concepts: heap property, swapping.