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