Merge pull request #631 from vaibhav0726/patch-1

added heap sort algo in python

Python/Sorting-Techniques/heapSort.py

@@ -0,0 +1,36 @@
+def heapify(arr, N, i):
+	largest = i 
+	l = 2 * i + 1	 
+	r = 2 * i + 2	 
+
+	if l < N and arr[largest] < arr[l]:
+		largest = l
+
+	if r < N and arr[largest] < arr[r]:
+		largest = r
+
+	if largest != i:
+		arr[i], arr[largest] = arr[largest], arr[i]
+
+		heapify(arr, N, largest)
+
+def heapSort(arr):
+	N = len(arr)
+
+	for i in range(N//2 - 1, -1, -1):
+		heapify(arr, N, i)
+
+	for i in range(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")
+	for i in range(N):
+		print("%d" % arr[i], end=" ")
+