python_algorithm/qsort.py at master · acmerfight/python_algorithm · GitHub

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defqsort(arr):
iflen(arr) <=1:
returnarr
else:
returnqsort([xforxinarr[1:] ifx<arr[0]]) + [arr[0]] +qsort([xforxinarr[1:] ifx>=arr[0]])


defpartition(array, begin, end):
pivot=begin
foriinxrange(begin+1, end+1):
ifarray[i] <=array[begin]:
pivot+=1
array[i], array[pivot] =array[pivot], array[i]
array[pivot], array[begin] =array[begin], array[pivot]
returnpivot


defquicksort(array, begin=0, end=None):
ifendisNone:
end=len(array) -1
ifbegin>=end:
return
pivot=partition(array, begin, end)
quicksort(array, begin, pivot-1)
quicksort(array, pivot+1, end)


qsort([1, 23, 10, -9]) ==qsort([1, 23, 10, -9])