Hi all,

here is a list of some Sodokus to solve and test
your algorithms (i would like to see which one is
hardest for your script and how long does this take):

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

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

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


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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

cheers

Simon