快速排序 Python

#快速排序
d0 = [2, 15, 5, 9, 7, 6, 4, 12, 5, 4, 2, 64, 5, 6, 4, 2, 3, 54, 45, 4, 44]
d0_out = [2, 2, 2, 3, 4, 4, 4, 4, 5, 5, 5, 6, 6, 7, 9, 12, 15, 44, 45, 54, 64]  # 正确排序
def quiksort(a:list):
    d = [[],[],[]]
    mid = a[-1] #选一个基准值
    for i in a:
        if i < mid:#小于基准值的放左边
            d[0].append(i)
        elif i>mid:#大于基准值的放右边
            d[2].append(i)
        else: d[1].append(i)#中间放基准值

    # print(d[0],d[1],d[2])
    if len(d[0]) > 1:#大于基准值的子数组，递归
        d[0] = quiksort(d[0])
    if len(d[2]) > 1:#小于基准值的子数组，递归
        d[2] = quiksort(d[2])

    d[0].extend(d[1])#合并
    d[0].extend(d[2])
    return d[0]
print(quiksort(d0))