+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
         |           |           |           |
+  +--+  +  +--+--+  +  +--+--+  +--+  +--+  +
|     |  |  |        |  |     |     |  |     |
+--+  +--+  +  +--+--+  +  +--+--+  +--+  +--+
|     |     |  |     |     |     |  |     |  |
+  +--+  +  +  +  +  +--+  +  +  +  +  +--+  +
|  |     |  |  |  |  |     |  |        |     |
+  +  +--+--+  +  +  +  +--+--+--+  +--+  +--+
|     |        |  |  |        |  |  |        |
+--+--+  +--+--+--+  +--+--+  +  +  +  +  +  +
|     |     |        |     |  |     |  |  |  |
+  +  +--+  +  +--+--+  +  +  +--+  +  +--+  +
|  |        |     |     |  |  |  |  |  |     |
+  +--+--+--+  +  +  +--+  +  +  +  +  +  +--+
|  |     |     |  |     |  |  |        |     |
+  +  +  +  +--+  +  +  +  +  +--+--+--+--+  +
|     |  |     |  |  |  |  |        |        |
+--+--+  +--+  +  +--+  +  +--+--+  +  +--+--+
|     |     |  |  |     |     |     |     |  |
+  +  +  +--+  +  +  +--+--+  +  +--+  +  +  +
|  |  |        |     |     |     |     |     |
+  +  +--+--+--+--+--+--+  +--+--+  +--+--+--+
|  |              |  |           |  |        |
+  +--+  +--+--+  +  +  +--+--+--+  +--+--+  +
|     |        |     |                       |
+--+  +--+--+  +--+--+--+--+--+--+  +--+--+--+
|     |     |        |                 |     |
+  +--+  +  +--+--+  +--+  +--+--+  +  +  +  +
|        |        |        |        |     |   
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Solution[X]