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Need a practical solution to create a database of templates (5-5-5) for 15 puzzles

For the static template database (5-5-5), see this (pages 290 and 283) OR the explanation below. For What is a 15-puzzle?
I am creating a static patter database (5-5-5). This code fills the records in the first table. I do this through a recursive function insertInDB(). The first input for a recursive function is this (in fact, the input puzzle contains it in a 1-D array. For a better understanding, I presented it as 2-D below)

1 2 3 4
0 6 0 0
0 0 0 0
0 0 0 0

This is my code:

class DBClass
{
    public Connection connection;
     public ResultSet rs;
      public PreparedStatement ps1;
    public PreparedStatement ps2;
    public int k;
      String read_statement,insert_statement;

    public DBClass()
    {
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
            try {
                connection = DriverManager
                    .getConnection("jdbc:mysql://localhost/feedback?"
                        + "user=ashwin&password=ashwin&autoReconnect=true&useUnicode=true&characterEncoding=utf8&validationQuery=Select 1");
                insert_statement="insert into staticpdb1(hash,permutation,cost) values(?,?,?)";
                read_statement="select SQL_NO_CACHE * from staticpdb1 where hash=? and permutation= ? LIMIT 1";
                 ps1=connection.prepareStatement(read_statement, ResultSet.TYPE_SCROLL_SENSITIVE, 
                            ResultSet.CONCUR_UPDATABLE);
                ps2=connection.prepareStatement(insert_statement);
                k=0;
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
    }
    public int updateIfNecessary(FifteenPuzzle sub) 
       {
           String str=sub.toDBString();
           try
           {

               ps1.setInt(1, sub.hashcode());
               ps1.setString(2,str);
               rs=ps1.executeQuery();
           if(rs.next())
              {
                  //if a row exists, check if the cost is greater than sub's
                  int cost=rs.getInt(3);
                  if(sub.g_n<cost)  //if the cost of sub is less than db row cost
                  {
                      //replace the cost
                      rs.updateInt(3, sub.g_n);
                      rs.updateRow();
                      return 1;   //only examine - do not insert
                  }
                  else
                      return 0;   //dont examine - return

              }
           else
               return 2;      //insert and examine
           }
           catch(SQLException e)
           {

               System.out.println("here1"+e);
               System.err.println("reported recursion level was "+e.getStackTrace().length);
               return 0;
           }
           finally{

               try{
                   rs.close();}
               catch(final Exception e1)
               {
                   System.out.println("here2"+e1);
               }

           }


       }
    public void insert(FifteenPuzzle sub)
    {

        try{
        String str=sub.toDBString();


         ps2.setInt(1,sub.hashcode());
         ps2.setString(2, str);
         ps2.setInt(3,sub.g_n);
         ps2.executeUpdate();
         ps2.clearParameters();
        }catch(SQLException e)
        {
            System.out.println("here3"+e);
        }
    }

    public void InsertInDB(FifteenPuzzle sub) throws SQLException
       {

           System.out.println(k++);

           int i;

           int p=updateIfNecessary(sub);
          if(p==0)
          {
              System.out.println("returning");
           return;
          }
          if(p==2)
          {
          insert(sub);
          System.out.println("inserted");
          }


           //FifteenPuzzle temp=new FifteenPuzzle(sub.puzzle.clone(),2,sub.g_n);
           for(i=0;i<sub.puzzle.length;i++)
           {
               if(sub.puzzle[i]!=0)
               {

                   //check the positions it can be moved to
                   if(i%4!=0 && sub.puzzle[i-1]==0)  //left
                   {
                       //create another clone and increment the moves
                       FifteenPuzzle temp_inner=new FifteenPuzzle(sub.puzzle.clone(),2,sub.g_n+1);
                       //exchange positions
                        int t=temp_inner.puzzle[i];
                        temp_inner.puzzle[i]=temp_inner.puzzle[i-1];
                        temp_inner.puzzle[i-1]=t;
                        InsertInDB(temp_inner);
                   }
                   if(i%4!=3 && sub.puzzle[i+1]==0)  //right
                   {
                       //create another clone and increment the moves
                       FifteenPuzzle temp_inner=new FifteenPuzzle(sub.puzzle.clone(),2,sub.g_n+1);
                       //exchange positions
                        int t=temp_inner.puzzle[i];
                        temp_inner.puzzle[i]=temp_inner.puzzle[i+1];
                        temp_inner.puzzle[i+1]=t;
                        InsertInDB(temp_inner);
                   }
                   if(i/4!=0 && sub.puzzle[i-4]==0)  //up
                   {
                       //create another clone and increment the moves
                       FifteenPuzzle temp_inner=new FifteenPuzzle(sub.puzzle.clone(),2,sub.g_n+1);
                       //exchange positions
                        int t=temp_inner.puzzle[i];
                        temp_inner.puzzle[i]=temp_inner.puzzle[i-4];
                        temp_inner.puzzle[i-4]=t;
                        InsertInDB(temp_inner);
                   }
                   if(i/4!=3 && sub.puzzle[i+4]==0)  //down
                   {
                       //create another clone and increment the moves
                       FifteenPuzzle temp_inner=new FifteenPuzzle(sub.puzzle.clone(),2,sub.g_n+1);
                       //exchange positions
                        int t=temp_inner.puzzle[i];
                        temp_inner.puzzle[i]=temp_inner.puzzle[i+4];
                        temp_inner.puzzle[i+4]=t;
                        InsertInDB(temp_inner);

                  }
             }   
       }



insertInDB (FifteenPuzzle fp) (puzzle - FifteenPuzzle) - 1,2,3,4,0,6,0,0,0,0,0,0,0,0,0,0 ( , ). , , ; (- )

(5-5-5) 15-?

- , ( , 15-). - , , . . - 15-Puzzle. , 8-Puzzle, . , . , . , , . . , , . , , . , . , , , .
( ) , . patter - . , , . , , . 5-5-5 - , 3, 5 , 6 (6- - ).

- :

1 2 3 4
0 6 0 0
0 0 0 0
0 0 0 0

/number _of_moves , .
( db)

16!/(16-5)! = 524160


- updateIfNecessary(FifteenPuzzle) - , FifteenPuzzle . , , , . , , . - insert(FifteenPuzzle) .

. fifteenuzzle.g_n - . , , 0, incremented by1.

- Xss128m (1024, 512 256 ) .
7,500,000 ( System.out.println(k++);).

16!/(16-5)! = 524160


7 500 000 . - . 513423. , 10 000 . , , 1 30 . .

- . ?

+1
5

, , . , , ; , .

. DFS ( ). BFS, . , , . , .

6, .

Priority: Left, Right, Up, Down (as you gave)

DFS

1 2 3 4    1 2 3 4
0 6 0 0    6 0 0 0
0 0 0 0    0 0 0 0
0 0 0 0    0 0 0 0
  (0)        (1)

. , ( ). , . , . , .

1 2 3 4    1 2 3 4
0 0 0 0    0 0 0 0
6 0 0 0    0 0 0 0
0 0 0 0    6 0 0 0
  (2)        (3)

,

           State-1    State-2    State-3
1 2 3 4    1 2 3 4    1 2 3 4    1 2 3 4
0 0 0 0    0 0 0 0    0 0 0 0    0 0 0 0
0 0 0 0    0 0 0 0    0 0 0 0    0 0 0 0
6 0 0 0    0 6 0 0    0 0 6 0    0 0 0 6
  (3)        (4)        (5)        (6)

, State-1 2 ( 4) . , . , , .

BFS

1 2 3 4    1 2 3 4
0 6 0 0    6 0 0 0
0 0 0 0    0 0 0 0
0 0 0 0    0 0 0 0
  (0)        (1)

,

1 2 3 4    1 2 3 4
0 0 6 0    0 0 0 0
0 0 0 0    0 6 0 0
0 0 0 0    0 0 0 0
  (1)        (1)

6, . , , .

.

Initialize no_of_moves by 0
enqueue(startingPosition)
insertIntoDB(startingPattern, no_of_moves)
while((currentPattern = dequeue()) is not null)
    if(currentPattern is not already traversed)
        insertIntoDB(currentPattern);
        list<Pattern> allPatterns = patterns which can be reached from currentPattern in just 1 move
        no_of_moves++
        enqueue(allPatterns, no_of_moves)
    end if
end while

, , . , .

, ( traversed["1234060000000000"] = true or false). , 524160 .

+2

: java.lang.StackOverflowError. .

, .

+2

. , , , : StackOverflowError
mothod, , , .

+1

PreparedStatement , . . ps=connection.prepareStatement(read_statement); ps=connection.prepareStatement(insert_statement);. PreparedStatement ps.clearParameters(); ( ). , . , . (.. FifteenPuzzle temp=new FifteenPuzzle(sub.puzzle.clone(),2,sub.g_n);)

+1

, , . , , . :

  • , / . . .
  • / .

, , , , , . .

, , . , , :

  • You are trying to close your prepared state in a try or if-block. What should I do if you don’t click on the if block and you are caught in an exception before you have a chance to close resources? Your PreparedStatement and other resources will never be closed.
0
source

Source: https://habr.com/ru/post/1791186/

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