quick sort algorithm.py

def quickSort(alist):
   quickSortHelper(alist,0,len(alist)-1)
def quickSortHelper(alist,first,last):
   if first<last:
       splitpoint = partition(alist,first,last)
       quickSortHelper(alist,first,splitpoint-1)
       quickSortHelper(alist,splitpoint+1,last)
def partition(alist,first,last):
   pivotvalue = alist[first]
   leftmark = first+1
   rightmark = last
   done = False
   while not done:
       while leftmark <= rightmark and alist[leftmark] <= pivotvalue:
           leftmark = leftmark + 1
       while alist[rightmark] >= pivotvalue and rightmark >= leftmark:
           rightmark = rightmark -1
       if rightmark < leftmark:
           done = True
       else:
           temp = alist[leftmark]
           alist[leftmark] = alist[rightmark]
           alist[rightmark] = temp
   temp = alist[first]
   alist[first] = alist[rightmark]
   alist[rightmark] = temp
   return rightmark
alist = ["Bhushan","Akshay","Chloe","Elbert","Dave"]
quickSort(alist)
print(alist)