Interactive DSA and system design

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74stepsO(n log n)averageO(1)space

Sorting lab

Heap Sort Build and Extract Flow

Step 1 / 74

Comparing Pivot / Mid Swapping Sorted / Found Active Range

Animation speed

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Current operation

Start

Heap Sort begins by building a max-heap from the unsorted array.

Try your own input

Use 3-12 positive numbers separated by commas.

Complexity notes

O(n log n)averageO(n log n)worstO(1)spaceNostable

Synced code trace

function heapSort(arr) {  buildMaxHeap(arr);  for (let i = n - 1; i > 0; i--) {    swap(arr, 0, i);    heapify(arr, 0, i);  }}function heapify(arr, root, size) {  let largest = root;  // compare children, swap if needed  if (largest !== root) heapify(arr, largest, size);}

Interactive Notes

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