+---------------------+
|   Down (default)    |
|        +----+       |
|        | a  |       |
|        |    |       |
|        +----+       |
|          |          |
|          v          |
|        +----+       |
|        | b  |       |
|        |    |       |
|        +----+       |
|          |          |
|          v          |
|        +----+       |
|        | c  |       |
|        |    |       |
|        +----+       |
|                     |
+---------------------+
           |           
           v           
   +--------------+    
   |    Right     |    
   |              |    
   |     +----+   |    
   |     | a  |   |    
   |     |    |   |    
   |     +----+   |    
   |       |      |    
   |       v      |    
   |     +----+   |    
   |     | b  |   |    
   |     |    |   |    
   |     +----+   |    
   |       |      |    
   |       v      |    
   |     +----+   |    
   |     | c  |   |    
   |     |    |   |    
   |     +----+   |    
   |              |    
   +--------------+    
           |           
           v           
   +---------------+   
   |     Left      |   
   |               |   
   |     +----+    |   
   |     | a  |    |   
   |     |    |    |   
   |     +----+    |   
   |       |       |   
   |       v       |   
   |     +----+    |   
   |     | b  |    |   
   |     |    |    |   
   |     +----+    |   
   |       |       |   
   |       v       |   
   |     +----+    |   
   |     | c  |    |   
   |     |    |    |   
   |     +----+    |   
   |               |   
   +---------------+   
           |           
           v           
   +---------------+   
   |      Up       |   
   |               |   
   |     +----+    |   
   |     | a  |    |   
   |     |    |    |   
   |     +----+    |   
   |       |       |   
   |       v       |   
   |     +----+    |   
   |     | b  |    |   
   |     |    |    |   
   |     +----+    |   
   |       |       |   
   |       v       |   
   |     +----+    |   
   |     | c  |    |   
   |     |    |    |   
   |     +----+    |   
   |               |   
   +---------------+   
