-------------------------------------
|     7     |         6 |     3     |
|   +   +   +   +   +   +   +   +   |
| 1         |           |         6 |
|   +   +   +   +   +   +   +   +   |
|           | 9         | 2   4     |
|---+---+---+---+---+---+---+---+---|
|           | 3         |     6     |
|   +   +   +   +   +   +   +   +   |
|     1     | 2         |           |
|   +   +   +   +   +   +   +   +   |
| 8   6     |         7 |     5   2 |
|---+---+---+---+---+---+---+---+---|
|           | 7         |     9     |
|   +   +   +   +   +   +   +   +   |
|         6 | 1         |         3 |
|   +   +   +   +   +   +   +   +   |
| 7   3     |           |         8 |
-------------------------------------

          DIFFICULTY: 2.75