希尔排序

	// 希尔排序
	private static void ShellSort(int a[]) {
		for (int s = 5; s > 0; s -= 2) {
			for (int i = 0; i < a.length; i++) {
				for (int j = i + s; j < a.length; j += s) {
					for (int k = j; k - s >= 0; k -= s) {
						if (a[k] < a[k - s]) {
							int temp = a[k];
							a[k] = a[k - s];
							a[k - s] = temp;
						}
					}
				}
			}
		}
	}