python-实现希尔排序

# encoding=utf-8

def shell_sort(alist):
    """希尔排序"""
    n = len(alist)
    gap = n // 2
    while gap >= 1:
        for j in range(gap, n):
            i = j
            while (i-gap) >= 0:
                if alist[i] < alist[i-gap]:
                    alist[i], alist[i-gap] = alist[i-gap], alist[i]
                    i -= gap
                else:
                    break
        gap //= 2

if __name__ == ‘__main__‘:
    alist = [22, 1, 4, 553, 3, 212, 77]
    print(alist)
    shell_sort(alist)
    print(alist)