heapSort.py

defheapify(arr, N, i):
largest=i
l=2*i+1
r=2*i+2

ifl<Nandarr[largest] <arr[l]:
largest=l

ifr<Nandarr[largest] <arr[r]:
largest=r

iflargest!=i:
arr[i], arr[largest] =arr[largest], arr[i]

heapify(arr, N, largest)

defheapSort(arr):
N=len(arr)

foriinrange(N//2-1, -1, -1):
heapify(arr, N, i)

foriinrange(N-1, 0, -1):
arr[i], arr[0] =arr[0], arr[i]
heapify(arr, i, 0)

if__name__=='__main__':
arr= [12, 11, 13, 5, 6, 7]

heapSort(arr)
N=len(arr)

print("Sorted array is")
foriinrange(N):
print("%d"%arr[i], end=" ")