leetcode 字符串分割对称

 public class Solution {
     public List<List<String>> partition(String s) {
         int len=s.length();
            boolean dp[][]=new boolean[len][len];
            get(dp,s);
            ArrayList<ArrayList<String>> res=new ArrayList<ArrayList<String>>();
            ArrayList<String> temp=new ArrayList<String>();
            dfs(res,temp,0,dp,s);
            return (List)res;

     }
     public void get(boolean dp[][],String s)
     {
         char c[]=s.toCharArray();
         int len=s.length();
       //single character is duichen
       for(int i=0;i<len-1;i++)
       {
           dp[i][i]=true;
           if(c[i]==c[i+1]) dp[i][i+1]=true;

       }
       dp[len-1][len-1]=true;

         for(int l=2;l<len;l++)
         {
             for(int k=0;k<len-l;k++)
             {
                 dp[k][k+l]=dp[k+1][k+l-1]&&(c[k]==c[k+l]);
             }

         }

     }
 public void dfs(ArrayList<ArrayList<String>> res,ArrayList<String> temp,int l,boolean dp[][],String s)
     {
         if(l==dp.length)
         {
            res.add(new ArrayList(temp));
         }
         else
         {
             for(int j=0;j<dp.length;j++)
             {
                 if(dp[l][j])
                 {
                     ArrayList<String> t=new ArrayList<String>(temp);
                     t.add(s.substring(l,j+1));
                     dfs(res,t,j+1,dp,s);

                 }

             }

              }
     }

 }