## 快速排序的平均运行时间为O(n log n),在最糟糕的情况下运行时间为O(n2)
1 def quick_sort(arr): 2 if len(arr) < 2: 3 return arr 4 pivot = arr[0] 5 less = [i for i in arr[1:] if i < pivot] 6 greater = [i for i in arr[1:] if i >= pivot] 7 return quick_sort(less) + [pivot] + quick_sort(greater) 8 9 print(quick_sort([3, 5, 47, 8, 34, 2, 34, 2, 56, 5, 7, 76, 23, 4, 213, 12])) 10 # [2, 2, 3, 4, 5, 5, 7, 8, 12, 23, 34, 34, 47, 56, 76, 213]