python 快速排序

平均时间复杂度O（nlogn）

最坏情况O（n^2）

def quick(array):
    if len(array)<2:
        return array
    else:
        pivot_index = 0
        pivot = array[pivot_index]
        less_part = [i for i in array[pivot_index+1:]if i <pivot ]
        great_part = [i for i in array[pivot_index+1:]if i>pivot]
        return quick(less_part) + [pivot]+quick(great_part)
a = [7,24,3,12,44,6]
print(quick(a))