def bubbleSort(alist):
for passnum in range(len(alist)-1,0,-1):
for i in range(passnum):
if alist[i]>alist[i+1]:
#temp = alist[i]
#alist[i] = alist[i+1]
#alist[i+1] = temp
alist[i],alist[i+1]=alist[i+1],alist[i]
def shortBubbleSort(alist):
exchanges = True
passnum = len(alist)-1
while passnum > 0 and exchanges:
exchangs = False
for i in range(passnum):
if alist[i]>alist[i+1]:
exchanges = True
temp = alist[i]
alist[i] = alist[i+1]
alist[i+1] = temp
passnum = passnum - 1
def selectionSort(alist):
for fillslot in range(len(alist)-1,0,-1):
positionOfMax=0
for location in range(1,fillslot+1):
if alist[location]> alist[positionOfMax]:
positionOfMax = location
temp=alist[fillslot]
alist[fillslot]=alist[positionOfMax]
alist[positionOfMax]=temp
def insertionSort(alist):
for index in range(1,len(alist)):
currentvalue = alist[index]
position = index
while position>0 and alist[position-1]>currentvalue:
alist[position]=alist[position-1]
position=position-1
alist[position]=currentvalue
def shellSort(alist):
sublistcount = len(alist)//2
print(sublistcount)
while sublistcount > 0:
for startposition in range(sublistcount):
gapInsertionSort(alist,startposition,sublistcount)
print("After increment of size",sublistcount,"The list is",alist)
sublistcount = sublistcount // 2
def gapInsertionSort(alist,start,gap):
for i in range(start+gap,len(alist),gap):
currentvalue = alist[i]
position = i
while position >= gap and alist[position-gap] > currentvalue:
alist[position]=alist[position-gap]
position=position-gap
alist[position]=currentvalue
def mergeSort(alist):
print("Splitting ",alist)
if len(alist)>1:
mid = len(alist)//2
lefthalf = alist[:mid]
righthalf = alist[mid:]
mergeSort(lefthalf)
mergeSort(righthalf)
i=0
j=0
k=0
while i < len(lefthalf) and j < len(righthalf):
if lefthalf[i] < righthalf[j]:
alist[k]=lefthalf[i]
i=i+1
else:
alist[k]=righthalf[j]
j=j+1
k=k+1
while i < len(lefthalf):
alist[k]=lefthalf[i]
i=i+1
k=k+1
while j < len(righthalf):
alist[k]=righthalf[j]
j=j+1
k=k+1
print("Merging ",alist)
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)