    x x   x x x x   x x      
                             
                  x   x     x
                             
  x               x x     x x
                             
x         x       x   x     x
                             
  x     x         x x x      
                             
x         x x x   x x x   x x
                             
            x     x x   x   x
                             
x x           x   x       x  
