常用排序算法（python）

def bubbleSort(alist):
    for i in range(len(alist)):
        for j in range(len(alist)-i-1):
            if alist[j]>alist[j+1]:
                tmp = alist[j]
                alist[j] = alist[j+1]
                alist[j+1] = tmp

def selectSort(alist):
    for i in range(len(alist)):
        minPos = i
        for j in range(i+1, len(alist)):
            if alist[i]>alist[j]:
                minPos = j
        tmp = alist[i]
        alist[i] = alist[minPos]
        alist[minPos] = tmp

def insertSort(alist):
    for i in range(1, len(alist)):
        current = alist[i]
        pos = i
        while pos>0 and current<alist[pos-1]:
            alist[pos] = alist[pos-1]
            pos-=1
        alist[pos] = current

def shellSort(alist):
    gap = len(alist)//2
    while gap>0:
        for i in range(gap, len(alist)):
            j = i
            current = alist[i]
            while j-gap>0 and current<alist[j-gap]:
                alist[j] = alist[j-gap]
                j = j - gap
            alist[j] = current
        gap = gap // 2

def mergeSort(alist):
    if len(alist)>1:
        mid = len(alist) // 2
        left = alist[:mid]
        right = alist[mid:]
        
        mergeSort(left)
        mergeSort(right)
        
        i,j,k = 0,0,0
        while i<len(left) and j<len(right):
            if left[i]<right[j]:
                alist[k] = left[i]
                i+=1
            else:
                alist[k] = right[j]
                j+=1
            k+=1
        while i<len(left):
            alist[k] = left[i]
            k+=1
            i+=1
        while j<len(right):
            alist[k] = right[j]
            k+=1
            j+=1

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):
    pivot = alist[first]
    leftmark = first + 1
    rightmark = last
    done = False
    while not done:
        while leftmark <= rightmark and alist[leftmark] <= pivot:
            leftmark += 1
        while rightmark >= leftmark and alist[rightmark] >= pivot:
            rightmark -= 1
        if rightmark < leftmark:
            done = True
        else:
            tmp = alist[leftmark]
            alist[leftmark] = alist[rightmark]
            alist[rightmark] = tmp
    tmp = alist[first]
    alist[first] = alist[rightmark]
    alist[rightmark] = tmp
    return rightmark