+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
   |           |           |  |     |        |
+  +--+--+--+  +  +--+--+  +  +  +  +  +--+  +
|     |  |     |  |        |     |  |     |  |
+--+  +  +  +--+  +  +--+--+  +--+  +--+  +--+
|     |           |        |  |  |           |
+  +--+  +--+--+--+--+  +--+  +  +--+--+  +  +
|  |  |     |        |     |     |        |  |
+  +  +--+  +  +--+  +--+  +--+  +  +--+--+  +
|           |     |  |  |     |  |     |  |  |
+--+  +--+--+--+  +  +  +  +  +--+--+  +  +  +
|  |           |  |     |  |     |     |     |
+  +--+--+--+  +  +  +--+--+--+  +  +--+--+--+
|  |     |     |  |        |     |        |  |
+  +  +  +  +--+  +--+--+  +  +--+  +--+  +  +
|     |     |  |     |     |     |     |  |  |
+--+--+--+--+  +--+  +  +--+--+  +--+  +  +  +
|           |        |  |     |     |  |  |  |
+  +--+--+  +--+--+  +--+  +  +--+  +  +  +  +
|  |     |        |        |        |  |     |
+  +  +  +  +--+--+--+  +--+--+  +--+--+  +  +
|     |  |  |           |     |           |  |
+--+--+  +  +  +--+--+--+  +  +--+--+--+--+  +
|     |  |              |  |  |              |
+  +  +  +--+--+--+--+--+  +  +  +--+--+--+  +
|  |  |     |     |     |  |  |     |        |
+  +  +--+  +--+  +  +  +  +--+  +  +--+  +--+
|  |     |     |  |  |  |     |  |  |     |  |
+  +--+  +--+  +  +--+  +--+  +--+  +  +--+  +
|     |        |                    |         
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+