x|-1--4--2--0---0--7--3--4--3--7--9--9--9--0--
x|--------------------------------------------
x|--------------------------------------------
x|--------------------------------------------
x|--------------------------------------------
x--------------------------------------------


x|-2--5--4--3----6--7--4--7-3-7-33-6-
x|---5--6--4---0----------------33-6-
x|--------------------5--5--5--------
x|-----------------------------------
x|-----------------------------------
x|-----------------------------------




x|-1-2--5-7-7-4-8-9----0-0-0-0-0-123
x|-1-2--5-7-4-3----------0----0----0
x|-0-------------0-0-0-0-0------0---
x|----------------------------------
x|----------------------------------
x|----------------------------------