+---+---+---+---+               +---+---+---+---+
|   | 5 | 5 |   |               |   | 6 |   | 6 |
+---+---+---+---+               +---+---+---+---+
| 5 |   |   | 5 |               | 6 |   |   |   |
+---+---+---+---+               +---+---+---+---+
| 5 |   |   | 5 |               |   |   |   | 6 |  
+---+---+---+---+               +---+---+---+---+
|   | 5 | 5 |   |               | 6 |   | 6 |   | 
+---+---+---+---+               +---+---+---+---+ 
                               

                  +---+---+---+---+            
                  |   |   |   |   |             
                  +---+---+---+---+            
                  |   |   |   |   |           
                  +---+---+---+---+           
                  |   |   |   |   |          
                  +---+---+---+---+            
                  |   |   |   |   |          
                  +---+---+---+---+ 

1. Each watchman looks in all directions on a square board (horizontal, vertical and both diagonals).
2. A watchman can see beyond another watchman.
3. On the left board, each watchman has five vacant cells under his gaze.
4. On the right board, each watchman can see six empty cells.

What is the maximum number of watchmen that can be placed so that each sees seven empty cells?