说明：  　最坏时间复杂度为O(n^2)；最优时间复杂度为O(n)；平均时间复杂度为O(n^1.3)。辅助空间O(1)。稳定性：不稳定。希尔排序的时间复杂度与选取的增量有关，选取合适的增量可减少时间复杂度。 基本思想为在直接插入排序的思想下设置一个最小增量dk,刚开始dk设置为n/2。进行插入排序，随后再让dk=dk/2,再进行插入排序，直到dk为1时完成最后一次插入排序，此时数组完成排序。
(The worst time complexity is O (n ^ 2); the optimal time complexity is O (n); and the average time complexity is O (n ^ 1.3). Auxiliary space O(1). Stability: Instability. The time complexity of Hill sorting is related to the increment of selection, and the appropriate increment can reduce the time complexity. The basic idea is to set a minimum incremental DK under the idea of direct insertion sort, and at the beginning DK is set to n/2. The insertion sort is performed, then DK = Dk / 2 is allowed, and then the insertion sort is performed until the last insertion sort is completed when DK is 1, when the array completes the sort.)