    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   x x x     x
