     

                  ○     ×       

               ○×○○×                        
               ×○○×○             
              ○××○×                 
              ×○×○○                   
                ○×○××                   
              ○×○×○                        
              ×○×○×                        
               ××○○×            
                ○○××○                      
               ××○×○                            
              ○○×○×                    
             ○○××○                    
            ××○××            
            ○○○×○                
              ×××○×                  
            ×○○○○                
            ○××××              
             ××○○○                
              ○○○××                       
                ○○×××               
             ×××○○               
             ○○○○×                      
            ×××××                     
            ○○○○○                      
             ×○○○×                      
           ○×××○                    
           ×○○××                   
             ○××○○                        
              ×○×××            
               ○×○○○                    
             ×○××○             
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