Heapify method rearranges the elements of an array where the left and right sub-tree of ith element obeys the heap property.
Algorithm: Max-Heapify(numbers[], i) leftchild := numbers[2i] rightchild := numbers [2i + 1] if leftchild ≤ numbers[].size and numbers[leftchild] > numbers[i] largest := leftchild else largest := i if rightchild ≤ numbers[].size and numbers[rightchild] > numbers[largest] largest := rightchild if largest ≠ i swap numbers[i] with numbers[largest] Max-Heapify(numbers, largest)
When the provided array does not obey the heap property, Heap is built based on the following algorithm Build-Max-Heap (numbers[]).
Algorithm: Build-Max-Heap(numbers[]) numbers[].size := numbers[].length fori = ⌊ numbers[].length/2 ⌋ to 1 by -1 Max-Heapify (numbers[], i)