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public class Solution {

    public boolean isMatch(String s, String p) {

        if(s==null && p==null||s.length()==0 && p.length()==0){

            return true;

        }

        if(s==null||p==null){

            return false;

        }

        List<String> tokens=parse(p);

        boolean[][] match=new boolean[s.length()+1][tokens.size()+1];

        match[0][0]=true;

        int match_len=s.length()+1;

        int token_len=tokens.size()+1;

       

        for(int i=1;i<match_len;i++){

            match[i][0]=false;

           

        }

        for(int n=1;n<token_len;n++){

            match[0]
=match[0][n-1]&&tokens.get(n-1).length()==2;

        }

        for(int i=1;i<match_len;i++){

            for(int j=1;j<token_len;j++){

                String curr=tokens.get(j-1);

                match[i][j]=curr.length() == 2 && match[i][j-1] ||

                          curr.length() == 2 && (curr.charAt(0) == '.' || curr.charAt(0) == s.charAt(i-1)) && match[i-1][j] ||

                          (curr.charAt(0) == '.' || curr.charAt(0) == s.charAt(i-1)) && match[i-1][j-1];

               

            }

        }

        return match[match_len-1][token_len-1];

    }

   

    public List<String> parse(String p){

        int i=0;

        List<String> result=new ArrayList<String>();

        while(i<p.length()){

            if(p.charAt(i)=='*'){

                i++;

               

            }else{

                if(i+1>=p.length()||p.charAt(i+1)!='*'){

                    result.add(p.substring(i,i+1));

                    i++;

                }else if(p.charAt(i+1)=='*'){

                    result.add(p.substring(i,i+2));

                    i+=2;

                }

            }

        }

        return result;

    }

}