X                  X       
XD                DX
XDD              DDX
XDDD            DDDX
XDDDD   D  D   DDDDX
XDDDDD DD  DD DDDDDX 
XDDDDD DD  DD DDDDDX             
X DDDDDDD  DDDDDDD X
X  DDDDDD  DDDDDD  X
X   DDDDD  DDDDD   X
X   DDDDD  DDDDD   X
X  DDDDDD  DDDDDD  X
X DDDDDDD  DDDDDDD X 
XDDDDD DD  DD DDDDDX
XDDDDD DD  DD DDDDDX
XDDDD   D  D   DDDDX
XDDD            DDDX
XDD              DDX
XD                DX
X                  X