How to Sort Using Heap Sort in Python?

Here is how to sort using Heap Sort in Python?
Run the code here: https://repl.it/@VinitKhandelwal/heap-sort

def max_heapify(A, heap_size, i):

    left = 2 * i + 1

    right = left + 1

    largest = i

    if left < heap_size and A[left] > A[largest]:

        largest = left

    if right < heap_size and A[right] > A[largest]:

        largest = right

    if largest != i:

        A[i], A[largest] = A[largest], A[i]

        max_heapify(A, heap_size, largest)

def build_heap(A):

    heap_size = len(A)

    for i in range (int(heap_size/2),-1,-1):

        max_heapify(A, heap_size, i)

def heapsort(A):

    heap_size = len(A)

    build_heap(A)

    #print A #uncomment this print to see the heap it builds

    for i in range(heap_size-1,0,-1):

        A[0], A[i] = A[i], A[0]

        heap_size -= 1

        max_heapify(A, heap_size, 0)

A = [2,8,1,4,14,7,16,10,9,3]

heapsort(A)

print(A)

OUTPUT

[1, 2, 3, 4, 7, 8, 9, 10, 14, 16]

TIME COMPLEXITY

O(n log n)

Comments

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