java非递归方式实现快速排序

Java非递归方式实现快速排序

package sort.algorithm;
import java.util.Stack;
//快速排序的非递归实现，利用系统的栈stack
public class QuickSortNonRecursion {
     public static void main(String[] args) { 
         QuickSortNonRecursion qsnr = new QuickSortNonRecursion(); 
         int[] array = {0, 2, 11, 121, 18, 99, 3, 5, 101, 22, 9, 100}; 
         qsnr.quicksort(array); 
          for (int i : array) { 
                System.out.print(i + "  "); 
          } 
        } 
                
        public void quicksort(int[] array) { 
            if (array == null || array.length == 1) return; 
            //存放开始与结束索引
            Stack s = new Stack();  
            //压栈        
            s.push(0);  
            s.push(array.length - 1);  
            //利用循环里实现
            while (!s.empty()) {  
                int right = s.pop();  
                int left = s.pop();  
                //如果最大索引小于等于左边索引，说明结束了
                if (right <= left) continue;  
                        
                int i = partition(array, left, right);  
                if (left < i - 1) { 
                    s.push(left); 
                    s.push(i - 1); 
                }  
                if (i + 1 < right) { 
                    s.push(i+1); 
                    s.push(right); 
                } 
            }  
        } 
        //找到轴心，进行交换 
        public int partition (int[] data, int first, int end)
        { 
            int temp;
            int i=first,j=end;
            if(firsti&&data[j]>temp)j--;
                    if(idata[i])i++;
                    if(i