12
8
+---+---+---+---+---+---+---+---+---+---+---+---+
|       |           |           |           |   |
+---+   +---+   +   +   +---+   +   +   +   +   +
|   |           |   |   |       |   |   |   |   |
+   +---+---+---+   +   +---+   +---+   +   +   +
|               |   |       |           |       |
+   +---+---+   +   +   +   +---+---+---+---+   +
|   |       |       |   |   |                   |
+   +   +---+---+---+---+   +---+---+   +---+---+
|   |                   |   |       |           |
+   +   +   +---+---+   +   +   +   +---+---+   +
|   |   |   |           |       |   |       |   |
+   +---+   +---+   +---+---+---+   +   +---+   +
|       |       |   |               |           |
+---+   +---+   +   +   +---+---+---+   +---+---+
|               |       |                       |
+---+---+---+---+---+---+---+---+---+---+---+---+
