(`)
--------------------------------
--------------------------------
--------2-2-------------2-2-----
0-0-4-4-----4---0-0-4-4-----4---
--------------------------------
----------------------------2-2-
--------2-2-------------2-2-----
0-0-4-4-----4---0-0-4-4---------
--------------------------------
--------------------------------
--------2-2-------------2-2-----
0-0-4-4-----4---0-0-4-4-----4---
--------------------------------
------------0-0-2-2-------------
--------2-2-------------2-2-----
0-0-4-4-------------4-4-----4---
--------------------------------
--------------------------------
--------------------------------
0-0---0---0---0---0---0---0---0-
--------------------------------
--------------------------------
--------------------------------
--0---0---0---0---0---0-3-23-45-
--------------------------------
--------------------------------
--------------------------------
0-0---0---0---0---0---0-3-0-5---
--------------------------------
--------------------------------
--------------------------------
0-0---0---0---0-0-0-3-04-05-0-3-
(a)
--------------------------------
--------------------------------
--------------------------------
5-5-5-3---0---3---0---3---0-0-3-
--------------------------------
------------------------------5-
--------------------------`7---
5-5-5-3---0---3---0-0---0-0-----
--------------------------------
7-7-7-5-------5-------5---------
----------7-------7-------------
--------------------------0-0-3-
--------------------------------
--------------------------------
--------------------------------
5-5-5-3---0---3---0-0---0-0-0-0-
(b)
--------------------------------
------------------------0-0-5-5-
----2-2-------------2-2---------
3-3-----3---3-3---3-------------
--------------------------------
----------------------------2-2-
------------------------2-2-----
0-0-4-4-0---0-0---0-4-4---------
--------------------------------
------------------------0-0-5-5-
----2-2-------------2-2---------
3-3-----3---3-3---3-------------
--------------------------------
--------2-2---------0-2-5-2-0---
0-0-4-4-----4-4-0-4-------------
--------------------------------
--------------------------------
--------------------------------
--------------------------------
0-0-0---0---0-0---0-0---0---5---
--------------------------------
--------------------------------
--------------------------------
0-0-0---0---0-0---0-0---0---5---
--------------------------------
--------------------------------
--------------------------------
0-0---0---0---0---0---0---0---0-
--------------------------------
------------------7-5---5-------
----------------------7---7-5---
--0---0---0---0-----------------
(c)
--------------------------------
2-2-----------------------------
--------2-2-------------2-2-----
----4-4-----4---0-0-4-4-----4---
--------------------------------
--------------------------------
-------------------------7-7-7--
0-0-4-4-----4---0-0-4-40--------
--------------------------------
2-2-----------------------------
--------2-2-------------2-2-----
----4-4-----4---0-0-4-4-----4---
--------------------------------
------------0-0-2-2-------------
--------2-2-------------2-2-----
0-0-4-4-------------4-4-----4---
--------------------------------
--------------------------------
7-------------------------------
--------------------------------
t
`|a|b|a|c