AlgorithmsByPython/QuickSort.py at master · DouTong/AlgorithmsByPython · GitHub

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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)
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defquickSort(alist):
quickSortHelper(alist, 0, len(alist)-1)

defquickSortHelper(alist, first, last):
iffirst<last:
splitPoint=partition(alist, first, last)

quickSortHelper(alist, first, splitPoint-1)
quickSortHelper(alist, splitPoint+1, last)

defpartition(alist, first, last):
pivotvlue=alist[first]

leftmark=first+1
rightmark=last
done=False

whilenotdone:
whilealist[leftmark] <=pivotvlueandleftmark<=rightmark:
leftmark+=1
whilealist[rightmark] >=pivotvlueandrightmark>=leftmark:
rightmark-=1

ifleftmark>rightmark:
done=True
else:
alist[leftmark], alist[rightmark] =alist[rightmark], alist[leftmark]
alist[rightmark], alist[first] =alist[first], alist[rightmark]
returnrightmark

alist= [54,26,93,17,77,31,44,55,20]
alist2= [1]
quickSort(alist2)
print(alist2)