The squares of the six polyominoes depicted below are either filled or empty. What logic was used to determine whether a square filled?

+--+--+--+--+--+              +--+--+
|##|  |##|  |##|              |##|##|
+--+--+--+--+--+  +--+--+     +--+--+
|  |  |  |  |     |##|##|     |##|##|
+--+--+--+--+  +--+--+--+--+  +--+--+
   |##|  |##|  |##|  |  |##|  |  |  |
   +--+--+--+  +--+--+--+--+  +--+--+
      |  |        |##|  |##|     |##|
      +--+        +--+--+--+--+  +--+
                     |##|  |##|
            +--+--+  +--+--+--+
            |  |##|     |##|
+--+--+  +--+--+--+--+  +--+
|##|##|  |##|  |  |  |
+--+--+  +--+--+--+--+     +--+
|##|##|        |##|##|     |##|
+--+--+--+--+  +--+--+  +--+--+--+
   |  |  |  |  |##|##|  |  |  |  |
   +--+--+--+  +--+--+  +--+--+--+
   |##|  |  |           |##|  |##|
   +--+--+--+           +--+--+--+

Draw a 5x5 grid.

Each piece with its corresponding piece obtained by a rotation of 180 degrees, placed in the 5x5 grid, make symetrical drawings in respect of the two main diagonals. 

Edited on November 24, 2005, 9:42 am

Edited on November 24, 2005, 9:47 am

Edited on November 24, 2005, 9:49 am

Edited on November 24, 2005, 1:59 pm

Posted by pcbouhid on 2005-11-24 09:38:31