package testFullPermutation;

 import java.util.ArrayList;

 import java.util.List;

 public class testFullPermutation

 {

     ArrayList<ArrayList<Integer>> fullPermutation=new ArrayList<ArrayList<Integer>>();

     public ArrayList<ArrayList<Integer>> allSort(int[] buf)

     {

         int end=buf.length;

         if (end==0)

         {

             return null;

         }

         else

         {

         fullPermutation=perm(buf,0,end-1);

         return fullPermutation;

         }

     }

     public ArrayList<ArrayList<Integer>> perm(int[] buf,int start,int end)

     {

         if (start==end)//

         {

             ArrayList<Integer> oneKind=new ArrayList<Integer>();

             for (int i=0;i<buf.length;i++)//递归终止条件

             {

                 oneKind.add(buf[i]);

             }

             fullPermutation.add(oneKind);

         }

         else

         {

             for (int i=start;i<=end;i++)

             {

                 int temp=buf[start];

                 buf[start]=buf[i];

                 buf[i]=temp;

                 perm(buf,start+1,end);

                 //还原成交换之前的组合

                 temp=buf[start];

                 buf[start]=buf[i];

                 buf[i]=temp;

             }

         }

         return fullPermutation;

     }

 }