package sort;
/**
*
* @author dreamtry
*
* Shell排序是以以一個量(sequence) 遞減的以步長(step)序列的排序,我這裏設的step爲6,
* 所以第一趟分別爲子數列(0,6)(1,7)(2,8)(3,9)(4,10)...分別進行排序
* 第二趟因爲sequence爲1,所以同插入排序
*
*/
public class ShellSort {
public void shellSort(int[] arr, int step){
int min;
int temp;
int sequence =1;
while(sequence < arr.length/step){
sequence = sequence*step +1; //產生到以step爲步長到arr.length的最大值.
}
while(sequence > 0){
for(int i = sequence; i < arr.length; i++){
temp = arr[i];
min = i;
while(min > sequence -1 && arr[min-sequence] > temp){
arr[min] = arr[min-sequence];
min = min - sequence;
}
arr[min] = temp;
}
sequence = (sequence-1)/step; //遞減序列關鍵字
}
}
public void print(int arr[]){
for(int i=0; i<arr.length; i++){
System.out.print(arr[i] + " ");
}
}
/**
* @param args
*/
public static void main(String[] args) {
int[] arr = {24,3,5,23,53,1,22,13,7,16,10,4};
System.out.print(arr.length +"\n");
int step = 5;
ShellSort demo = new ShellSort();
demo.shellSort(arr, step);
demo.print(arr);
}
}
/**
* 個人總結:shell排序當最後sequence=1時同插入排序,是插入排序的一種擴展,有錯請指正
*/