     //Creating the main sudoku board     int sudokuGraph[][] = new int[0][0];     public boolean attemptAssignValue(int leftIndex, int upIndex){         //Attempt to assign a value to the specified cell         for(int x = 0; x < 00 ; x++){             if(notContainedInRow(leftIndex, x) && notContainedInColumn(upIndex, x) && notContainedInSubGrid(leftIndex, upIndex, x)){                 sudokuGraph[leftIndex][upIndex] = x;                     return true;             }                            }          return false;     }      public boolean attemptAssignValue(int leftIndex, int upIndex