5
5
+---+---+---+---+---+
|               |   |
+---+---+---+   +   +
|           |       |
+   +---+---+---+   +
|               |   |
+   +---+   +---+   +
|   |   |   |       |
+   +   +   +   +---+
|       |           |
+---+---+---+---+---+
