Your target is to clean the table. The only action that you can do is to click two rows. If there is only one collision (a position where the pictures in both rows are different), a new row is generated by a combination of the selected ones. Look at the examples:
|
|
 |
|
| |
|
|
|
Impossible, two collisions
|
| |
|
|
|
Impossible, no collision
|
| |
|
|
|
|
An important notion is subsumption. A row A is subsumed by any other row B that can be obtained by deleting pictures to A. Some examples:
|
|
|
is subsumed by |
|
|
| |
|
|
|
is subsumed by |
|
|
Important. Any row is deleted when it becomes subsumed by another one.That is:
- When a new row is generated it removes all previous rows which become subsumed by the new one.
- If a new row is subsumed by any of the previous rows, it will not be generated.
Did you know? When you complete a level you have proved a theorem! The game is based on the resolution calculus. Each level comprises a set of unsatisfiable formulas. When you produce a new row you're making an inference. Finally, when you empty the table you have found a contradiction.
Hide instructions
