 
                                                 
                                                 6
                            
                                        6               
                            
                            
                     
                                                 19
                            
                                        19              
                            
                            
                     
                                                 2
                            
                                        2               
                            
                            
                     
                                                 15              
                            
                                        3D ture
                            
                                        15              
                            
                                        3D ture
                            
                    