Question

I need my program to print out execution time it took to compile, and show before quicksort and after. Heres my program so far. Its in python.

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 = [54,26,93,17,77,31,44,55,20]
quickSort(alist)
print(alist)

Answer 1

"""
  Python program to calculate the execution time of quick sort
"""

import time

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 = [54,26,93,17,77,31,44,55,20]
print("List before:", alist)
start = time.time()
quickSort(alist)
end = time.time()
timeTaken = end - start
print("List after:", alist)
print("Time Taken:", timeTaken)