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