import java.util.Random;   
   
public class RandomSort {   
    private Random random = new Random();   
    //數組大小   
    private static final int SIZE = 10;   
    //要重排序的數組   
    private int[] positions = new int[SIZE];   
       
    public RandomSort() {   
        for(int index=0; index<SIZE; index++) {   
            //初始化數組，以下標為元素值   
            positions[index] = index;   
        }   
        //順序打印出數組的值   
        printPositions(); 
    }   
       
    //重排序   
    public void changePosition() {   
        for(int index=SIZE-1; index>=0; index--) {   
            //從0到index處之間隨機取一個值，跟index處的元素交換   
            exchange(random.nextInt(index+1), index);   
        }   
        printPositions();   
    }   
       
    //交換位置   
    private void exchange(int p1, int p2) {   
        int temp = positions[p1];   
        positions[p1] = positions[p2];   
        positions[p2] = temp;  //更好位置 
    }   
       
    //打印數組的值   
    private void printPositions() {   
        for(int index=0; index<SIZE; index++) {   
            System.out.print(positions[index]+" ");            
        }   
        System.out.println();   
    }   
   
    public static void main(String[] args) {   
        RandomSort rs = new RandomSort();   
        rs.changePosition();   
        rs.changePosition();   
        rs.changePosition();   
    }   
}