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$ curl repovive.com/roadmaps/data-structures/heaps-priority-queues/extract-operation

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$ curl repovive.com/roadmaps/data-structures/heaps-priority-queues/extract-operation

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Extract Operation - Heaps & Priority Queues | Data Structures | Repovive

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Data Structures19 sections · 729 units49h total

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Extract Operation

Bubble down

To extract the minimum (in a min-heap):

$1.$ Save the root value.

$2.$ Move the last element to the root.

$3.$ "Bubble down": while larger than a child, swap with the smaller child.

$4.$ Return the saved value.

function extractMin(heap)
    minVal := heap[0]
    heap[0] := last element of heap
    remove last element
    bubbleDown(heap, 0)
    return minVal

Bubbling down takes at most $O(\log n)$ swaps.