4-6 python希尔排序

思想：希尔排序是插入排序的升级版

# 
def shell_srot(alist):
	n = len(alist)
	step = n // 4 
	i = 1
	while step >= 1:
		for j in range(step,n):
			while j > 0:
				if alist[j] > alist[j-step]:
					alist[j],alist[j-step] = alist[j-step],alist[j]
					j -= step
				else:
					break
		step //= 2
	return alist
if __name__ == '__main__':
	li = [12,42,43,12,43,12,1,4,6,32,1,0,325,52,23,132,7534,324,72,16]
	shell_sort(li)